Ship third-party license texts in plugin ZIPs (#345)

The drawio, excalidraw, and mermaid plugin packages redistribute
third-party material (the draw.io webapp, the Excalidraw editor and its
fonts, mermaid and its dependency tree) without the license texts their
licenses require. Every affected ZIP now carries a licenses/ directory:

- licenses/THIRD-PARTY-NOTICES.txt is generated from the esbuild
  metafile (packages/plugins/third-party-licenses.mjs), so the notice
  list is derived from what actually lands in plugin.js and cannot
  drift the way a hand-maintained list would.
- drawio additionally extracts the upstream LICENSE from the pinned
  release tarball (Apache-2.0 requires the text with redistribution);
  the extraction guard also heals vendor/ caches from before this
  change. The CI fast path (no vendor fetch, no ZIP) is unchanged.
- excalidraw additionally commits curated texts (MIT for Excalidraw,
  per-font OFL-1.1/MIT with each font's own copyright statement, plus
  a FONT-NOTICES.md attribution table), because neither the npm
  package nor upstream ships any license files for them.

The api-side package validator accepts additional ZIP entries, so
installed plugins are unaffected beyond the new files.

Closes #345

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012aoPvnakfBP28nAfijgUY9

.gitea/workflows/ci.yml

@@ -107,6 +107,24 @@ jobs:
             exit 1
           fi
 
+      # A fresh named volume inherits the ownership of the image directory it
+      # is mounted over. Every /data/… path the api image defaults to must
+      # therefore be pre-created AND chowned to `node`, or the non-root user
+      # cannot write to it — found on a real deploy in #303, where the env
+      # entry was added but the mkdir/chown line was not.
+      - name: api image pre-creates its data directories node-owned
+        run: |
+          set -euo pipefail
+          dirs=$(grep -oE '[A-Z_]+_DIR=/data/[a-z]+' apps/api/Dockerfile | cut -d= -f2 | sort -u)
+          bad=0
+          for d in $dirs; do
+            grep -q "mkdir -p .*$d" apps/api/Dockerfile || {
+              echo "$d is not pre-created in apps/api/Dockerfile"; bad=1; }
+            grep -q "chown -R node:node .*$d" apps/api/Dockerfile || {
+              echo "$d is not chowned to node in apps/api/Dockerfile"; bad=1; }
+          done
+          exit "$bad"
+
       - name: Set up pnpm
         uses: pnpm/action-setup@v4
 
@@ -327,6 +345,16 @@ jobs:
           E2E_BASE_URL=http://localhost:5173 \
             pnpm --filter @dorfteich/web exec playwright test e2e/social.spec.ts
 
+      - name: Reset login rate limit before admin-settings pack
+        run: |
+          echo "DELETE FROM rate_limits WHERE key LIKE 'login%';" | \
+            pnpm --filter @dorfteich/api exec prisma db execute --stdin --url "$DATABASE_URL"
+
+      - name: Run admin-settings pack
+        run: |
+          E2E_BASE_URL=http://localhost:5173 \
+            pnpm --filter @dorfteich/web exec playwright test e2e/admin-settings.spec.ts
+
       - name: Reset login rate limit before admin-quotas pack
         run: |
           echo "DELETE FROM rate_limits WHERE key LIKE 'login%';" | \
@@ -347,6 +375,18 @@ jobs:
           E2E_BASE_URL=http://localhost:5173 \
             pnpm --filter @dorfteich/web exec playwright test e2e/admin-users.spec.ts
 
+      - name: Reset login rate limit before invitations pack
+        run: |
+          echo "DELETE FROM rate_limits WHERE key LIKE 'login%';" | \
+            pnpm --filter @dorfteich/api exec prisma db execute --stdin --url "$DATABASE_URL"
+
+      # Invitations (issue #332) need the mail catcher like the auth pack:
+      # the invite link and the follow-up verification both travel by mail.
+      - name: Run invitations pack
+        run: |
+          E2E_BASE_URL=http://localhost:5173 E2E_MAILPIT_URL=http://mailpit:8025 \
+            pnpm --filter @dorfteich/web exec playwright test e2e/invitations.spec.ts
+
       - name: Reset login rate limit before permission-matrix pack
         run: |
           echo "DELETE FROM rate_limits WHERE key LIKE 'login%';" | \
@@ -620,6 +660,14 @@ jobs:
           E2E_BASE_URL=http://localhost:5173 \
             pnpm --filter @dorfteich/web exec playwright test e2e/a11y.spec.ts
 
+      # Das a11y-Pack kostet seit #301 einen Login mehr (der Reflow-Zaun);
+      # damit reicht das Budget nicht mehr bis in die VS-NfD-Packs → hier
+      # zusätzlich zurücksetzen (siehe Hinweis oben).
+      - name: Reset login rate limit before the VS-NfD packs
+        run: |
+          echo "DELETE FROM rate_limits WHERE key LIKE 'login%';" | \
+            pnpm --filter @dorfteich/api exec prisma db execute --stdin --url "$DATABASE_URL"
+
       # VS-NfD-Markierungen im Modus `marked` (issue #244).
       - name: Run VS-NfD marking pack
         run: |

CLAUDE.md

@@ -27,13 +27,3 @@ AA) — nicht nachträglich. Kurzfassung; Details und Begründung in
   machen — betroffene Specs mit anpassen (scopen), nicht das Label opfern.
 
 Verstöße gelten in Review und Abnahme als Funktionsfehler.
-
-## graphify
-
-This project has a knowledge graph at graphify-out/ with god nodes, community structure, and cross-file relationships.
-
-Rules:
-- For codebase questions, first run `graphify query "<question>"` when graphify-out/graph.json exists. Use `graphify path "<A>" "<B>"` for relationships and `graphify explain "<concept>"` for focused concepts. These return a scoped subgraph, usually much smaller than GRAPH_REPORT.md or raw grep output.
-- If graphify-out/wiki/index.md exists, use it for broad navigation instead of raw source browsing.
-- Read graphify-out/GRAPH_REPORT.md only for broad architecture review or when query/path/explain do not surface enough context.
-- After modifying code, run `graphify update .` to keep the graph current (AST-only, no API cost).

apps/api/Dockerfile

@@ -29,18 +29,19 @@ ARG APP_VERSION=0.0.0-dev
 # Default the data dirs to the writable, node-owned locations created below, so
 # the image works out of the box even where compose does not set them; compose
 # still mounts named volumes here for persistence (UPLOADS_DIR/PLUGINS_DIR).
-ENV NODE_ENV=production APP_VERSION=${APP_VERSION} UPLOADS_DIR=/data/uploads PLUGINS_DIR=/data/plugins SECRETS_FILE=/data/secrets/secrets.env BACKUPS_DIR=/data/backups
+ENV NODE_ENV=production APP_VERSION=${APP_VERSION} UPLOADS_DIR=/data/uploads PLUGINS_DIR=/data/plugins CUSTOM_FONTS_DIR=/data/fonts BRANDING_DIR=/data/branding SECRETS_FILE=/data/secrets/secrets.env BACKUPS_DIR=/data/backups
 WORKDIR /app
 COPY --from=build --chown=node:node /out /app
 # Generate the Prisma client for this image's platform.
 RUN node node_modules/prisma/build/index.js generate
-# A fresh named volume mounted at /data/uploads or /data/plugins is created
+# A fresh named volume mounted at /data/uploads, /data/plugins, /data/fonts
+# or /data/branding is created
 # root-owned; pre-creating them here (Docker copies an image directory's
 # ownership into a new volume on first mount) lets the non-root `node` user
 # write to them. /data/backups is mounted read-only here, but pre-creating it
 # node-owned keeps the shared `backups` volume writable for the backup
 # sidecar even when the api container is the one that initializes it.
-RUN mkdir -p /data/uploads /data/plugins /data/secrets /data/backups && chown -R node:node /data/uploads /data/plugins /data/secrets /data/backups
+RUN mkdir -p /data/uploads /data/plugins /data/fonts /data/branding /data/secrets /data/backups && chown -R node:node /data/uploads /data/plugins /data/fonts /data/branding /data/secrets /data/backups
 USER node
 EXPOSE 3000
 HEALTHCHECK --interval=30s --timeout=3s --retries=3 \

apps/api/prisma/migrations/20260731210000_plugin_bundle_hash/migration.sql

@@ -0,0 +1,4 @@
+-- #232: SHA-256 of the installed bundle ZIP, observed at install time.
+-- NULL for plugins installed before this migration — the admin UI says so
+-- and a reinstall records it.
+ALTER TABLE "plugins" ADD COLUMN "bundle_hash" TEXT;

apps/api/prisma/migrations/20260801120000_custom_fonts/migration.sql

@@ -0,0 +1,45 @@
+-- #303: operator-uploaded font families (ADR 0016 §#303).
+-- The bytes live on disk under CUSTOM_FONTS_DIR; these rows record only what
+-- the upload form stated, because the api never parses the font file.
+
+CREATE TABLE "custom_fonts" (
+    "id" TEXT NOT NULL,
+    "family" TEXT NOT NULL,
+    "slug" TEXT NOT NULL,
+    "category" TEXT NOT NULL,
+    "licence" TEXT NOT NULL,
+    "licence_url" TEXT,
+    "uploaded_by" TEXT NOT NULL,
+    "created_at" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    "updated_at" TIMESTAMP(3) NOT NULL,
+
+    CONSTRAINT "custom_fonts_pkey" PRIMARY KEY ("id")
+);
+
+-- Both unique: `family` keeps `fonts.<slot>.family` in pond settings
+-- unambiguous, `slug` owns a directory under CUSTOM_FONTS_DIR.
+CREATE UNIQUE INDEX "custom_fonts_family_key" ON "custom_fonts"("family");
+CREATE UNIQUE INDEX "custom_fonts_slug_key" ON "custom_fonts"("slug");
+
+ALTER TABLE "custom_fonts" ADD CONSTRAINT "custom_fonts_uploaded_by_fkey"
+    FOREIGN KEY ("uploaded_by") REFERENCES "users"("id")
+    ON DELETE RESTRICT ON UPDATE CASCADE;
+
+CREATE TABLE "custom_font_weights" (
+    "id" TEXT NOT NULL,
+    "font_id" TEXT NOT NULL,
+    "weight" INTEGER NOT NULL,
+    "has_woff" BOOLEAN NOT NULL DEFAULT false,
+    "byte_size" INTEGER NOT NULL,
+
+    CONSTRAINT "custom_font_weights_pkey" PRIMARY KEY ("id")
+);
+
+CREATE UNIQUE INDEX "custom_font_weights_font_id_weight_key"
+    ON "custom_font_weights"("font_id", "weight");
+
+-- Deleting a family takes its weights with it; the files on disk are removed
+-- by the service in the same operation.
+ALTER TABLE "custom_font_weights" ADD CONSTRAINT "custom_font_weights_font_id_fkey"
+    FOREIGN KEY ("font_id") REFERENCES "custom_fonts"("id")
+    ON DELETE CASCADE ON UPDATE CASCADE;

apps/api/prisma/migrations/20260805120000_invitations/migration.sql

@@ -0,0 +1,26 @@
+-- Peer invitations (issue #332): a user invites an e-mail address; the token
+-- allows exactly one registration even while registration is closed.
+
+-- CreateTable
+CREATE TABLE "invitations" (
+    "id" TEXT NOT NULL,
+    "inviter_id" TEXT NOT NULL,
+    "email" TEXT NOT NULL,
+    "token_hash" TEXT NOT NULL,
+    "expires_at" TIMESTAMP(3) NOT NULL,
+    "revoked_at" TIMESTAMP(3),
+    "accepted_at" TIMESTAMP(3),
+    "accepted_user_id" TEXT,
+    "created_at" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+
+    CONSTRAINT "invitations_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateIndex
+CREATE UNIQUE INDEX "invitations_token_hash_key" ON "invitations"("token_hash");
+
+-- CreateIndex
+CREATE INDEX "invitations_inviter_id_idx" ON "invitations"("inviter_id");
+
+-- AddForeignKey
+ALTER TABLE "invitations" ADD CONSTRAINT "invitations_inviter_id_fkey" FOREIGN KEY ("inviter_id") REFERENCES "users"("id") ON DELETE CASCADE ON UPDATE CASCADE;

apps/api/prisma/schema.prisma

@@ -31,46 +31,71 @@ enum UserStatus {
 /// Account profile. Login methods live in UserIdentity (OIDC-ready,
 /// ADR 0007); Site Admin is a user flag, all other roles are grants.
 model User {
-  id              String     @id @default(uuid())
-  username        String     @unique
-  email           String     @unique
-  displayName     String     @map("display_name")
-  locale          String     @default("en")
-  isSiteAdmin     Boolean    @default(false) @map("is_site_admin")
+  id                 String     @id @default(uuid())
+  username           String     @unique
+  email              String     @unique
+  displayName        String     @map("display_name")
+  locale             String     @default("en")
+  isSiteAdmin        Boolean    @default(false) @map("is_site_admin")
   /// True when the flag was last SET by the IdP claim mapping (issue #217):
   /// only then may the mapping revoke it again on a later login. A manual
   /// admin toggle clears the marker, so hand-granted admins are never
   /// demoted by a missing claim.
-  isSiteAdminManaged Boolean @default(false) @map("is_site_admin_managed")
+  isSiteAdminManaged Boolean    @default(false) @map("is_site_admin_managed")
   /// Auto-watch preferences (issue #93): watch pages I create / comment on.
-  autoWatchOwnPages  Boolean @default(true) @map("auto_watch_own_pages")
-  autoWatchOnComment Boolean @default(true) @map("auto_watch_on_comment")
+  autoWatchOwnPages  Boolean    @default(true) @map("auto_watch_own_pages")
+  autoWatchOnComment Boolean    @default(true) @map("auto_watch_on_comment")
   /// E-mail digest cadence (issue #95): hourly | daily | off.
-  digestFrequency    String  @default("hourly") @map("digest_frequency")
-  status          UserStatus @default(PENDING_VERIFICATION)
-  emailVerifiedAt DateTime?  @map("email_verified_at")
-  createdAt       DateTime   @default(now()) @map("created_at")
-  lastLoginAt     DateTime?  @map("last_login_at")
+  digestFrequency    String     @default("hourly") @map("digest_frequency")
+  status             UserStatus @default(PENDING_VERIFICATION)
+  emailVerifiedAt    DateTime?  @map("email_verified_at")
+  createdAt          DateTime   @default(now()) @map("created_at")
+  lastLoginAt        DateTime?  @map("last_login_at")
 
-  identities      UserIdentity[]
-  sessions        Session[]
-  authTokens      AuthToken[]
-  apiTokens       ApiToken[]
-  feedTokens      FeedToken[]
-  mentionRows     PageMention[]
-  ponds           Pond[]
-  pages           Page[]
-  attachments     Attachment[]
-  conversionJobs  ConversionJob[]
-  auditEntries    AuditEntry[]
-  comments        Comment[]
-  watches         Watch[]
-  notifications   Notification[]
-  favorites       PageFavorite[]
+  identities     UserIdentity[]
+  sessions       Session[]
+  authTokens     AuthToken[]
+  apiTokens      ApiToken[]
+  feedTokens     FeedToken[]
+  mentionRows    PageMention[]
+  ponds          Pond[]
+  pages          Page[]
+  attachments    Attachment[]
+  conversionJobs ConversionJob[]
+  auditEntries   AuditEntry[]
+  comments       Comment[]
+  watches        Watch[]
+  notifications  Notification[]
+  favorites      PageFavorite[]
+  customFonts    CustomFont[]
+  invitations    Invitation[]   @relation("InvitationsSent")
 
   @@map("users")
 }
 
+/// Peer invitations (issue #332): a user invites an e-mail address; the
+/// token allows exactly one registration even while registration is
+/// closed. Only the SHA-256 hash of the token is stored (auth-tokens
+/// pattern); revoked/accepted rows are kept so the settings UI can show
+/// history. "Open" (pending, unexpired) rows count against the per-user
+/// quota `invitations.maxOpenPerUser`.
+model Invitation {
+  id             String    @id @default(uuid())
+  inviterId      String    @map("inviter_id")
+  email          String
+  tokenHash      String    @unique @map("token_hash")
+  expiresAt      DateTime  @map("expires_at")
+  revokedAt      DateTime? @map("revoked_at")
+  acceptedAt     DateTime? @map("accepted_at")
+  acceptedUserId String?   @map("accepted_user_id")
+  createdAt      DateTime  @default(now()) @map("created_at")
+
+  inviter User @relation("InvitationsSent", fields: [inviterId], references: [id], onDelete: Cascade)
+
+  @@index([inviterId])
+  @@map("invitations")
+}
+
 /// Persistent audit trail (issue #86, security.md §Logging): auth events and
 /// admin actions — grants, member roles, plugin installs, quota and settings
 /// changes, setup steps, manual job triggers. Written by AuditService, which
@@ -107,32 +132,32 @@ model AuditEntry {
 /// lives per partition there (a partitioned parent cannot carry it without
 /// the partition key); `db push` test databases get it on the plain table.
 model ReadEvent {
-  id         String   @default(uuid())
-  occurredAt DateTime @default(now()) @map("occurred_at")
+  id             String   @default(uuid())
+  occurredAt     DateTime @default(now()) @map("occurred_at")
   /// Null = anonymous reader (public grant); `sessionKey` still names the
   /// browsing session, so the anonymous marker is explicit, not an accident.
-  actorId    String?  @map("actor_id")
+  actorId        String?  @map("actor_id")
   /// `session:<id>` for cookie sessions, `token:<id>` for PATs, `job:<id>`
   /// for background builds (account data export), `anon` for anonymous
   /// visitors — the dedup-window key basis (#223).
-  sessionKey String   @map("session_key")
-  pageId     String?  @map("page_id")
-  pondId     String   @map("pond_id")
+  sessionKey     String   @map("session_key")
+  pageId         String?  @map("page_id")
+  pondId         String   @map("pond_id")
   /// Which read surface fired: `page_view` | `no_js_shell` | `public_api` |
   /// `attachment` | `export` | `collab_join` (READ_CHANNELS union in code).
-  channel    String
+  channel        String
   /// Classification at read time — a later reclassification must not
   /// rewrite history (ADR 0023).
   classification String
-  details    Json?
+  details        Json?
   /// Dedup window (issue #223): `<sessionKey>:<pageId|->:<channel>` plus the
   /// aligned bucket `floor(epoch / windowSeconds)`. The unique pair makes
   /// concurrent duplicate reads collapse race-free (insert or P2002-skip).
-  dedupKey      String @map("dedup_key")
-  windowBucket  BigInt @map("window_bucket")
+  dedupKey       String   @map("dedup_key")
+  windowBucket   BigInt   @map("window_bucket")
   /// Window length the event was recorded under — the row itself states it
   /// represents up to this many seconds, so the evidence is not overread.
-  windowSeconds Int    @map("window_seconds")
+  windowSeconds  Int      @map("window_seconds")
 
   @@id([id, occurredAt])
   @@unique([dedupKey, windowBucket])
@@ -237,14 +262,14 @@ model Pond {
   deletedAt   DateTime? @map("deleted_at")
   deletedBy   String?   @map("deleted_by")
 
-  owner       User         @relation(fields: [ownerId], references: [id])
-  usage       PondUsage?
-  pages       Page[]
-  attachments Attachment[]
-  labels      Label[]
-  grants      RoleGrant[]
+  owner          User            @relation(fields: [ownerId], references: [id])
+  usage          PondUsage?
+  pages          Page[]
+  attachments    Attachment[]
+  labels         Label[]
+  grants         RoleGrant[]
   conversionJobs ConversionJob[]
-  pondPlugins PondPlugin[]
+  pondPlugins    PondPlugin[]
 
   @@index([ownerId])
   @@map("ponds")
@@ -460,12 +485,12 @@ model CollabOpenSession {
 /// built from the Yjs state via the shared editor schema. `outline` is the
 /// heading tree (`OutlineEntry[]` from @dorfteich/shared) as jsonb.
 model PageContentCache {
-  pageId    String   @id @map("page_id")
-  plainText String   @map("plain_text")
-  markdown  String
-  html      String
-  outline   Json
-  updatedAt DateTime @updatedAt @map("updated_at")
+  pageId       String                   @id @map("page_id")
+  plainText    String                   @map("plain_text")
+  markdown     String
+  html         String
+  outline      Json
+  updatedAt    DateTime                 @updatedAt @map("updated_at")
   /// Weighted full-text search vector (title A, labels B, body C; issue #49,
   /// ADR 0010). Maintained by the SearchProvider and the collab persistence
   /// hook (both write it with the same weighting). The GIN index is added in
@@ -854,9 +879,9 @@ model ConversionJob {
   sourceName   String? @map("source_name")
   resultPageId String? @map("result_page_id")
 
-  owner  User  @relation(fields: [ownerId], references: [id], onDelete: Cascade)
-  pond   Pond? @relation(fields: [pondId], references: [id], onDelete: Cascade)
-  page   Page? @relation(fields: [resultPageId], references: [id], onDelete: SetNull)
+  owner User  @relation(fields: [ownerId], references: [id], onDelete: Cascade)
+  pond  Pond? @relation(fields: [pondId], references: [id], onDelete: Cascade)
+  page  Page? @relation(fields: [resultPageId], references: [id], onDelete: SetNull)
 
   @@index([status, createdAt])
   @@map("conversion_jobs")
@@ -885,6 +910,8 @@ model Plugin {
   mode        PluginInstanceMode @default(DISABLED)
   /// The full manifest as validated at install time (@dorfteich/plugin-sdk).
   manifest    Json
+  /// SHA-256 (hex) of the installed bundle ZIP (#232); null = pre-#232 install.
+  bundleHash  String?            @map("bundle_hash")
   installedAt DateTime           @default(now()) @map("installed_at")
   updatedAt   DateTime           @updatedAt @map("updated_at")
   /// Set when uninstalled; active queries filter `removedAt: null`.
@@ -911,3 +938,48 @@ model PondPlugin {
   @@id([pondId, pluginId])
   @@map("pond_plugins")
 }
+
+/// An operator-uploaded font family (issue #303, ADR 0016 §#303). The bytes
+/// live on disk under CUSTOM_FONTS_DIR — this row only records what the
+/// upload form stated, because the api never parses the font file itself.
+/// Additive to the compile-time catalog: a family whose name or slug
+/// collides with a catalog entry is rejected, so `fonts.<slot>.family` in a
+/// pond's settings stays unambiguous.
+model CustomFont {
+  id         String   @id @default(uuid())
+  /// CSS `font-family` name, as typed by the uploader.
+  family     String   @unique
+  /// URL/file-safe form; names the directory under CUSTOM_FONTS_DIR.
+  slug       String   @unique
+  /// Drives the system fallback stack, like FontCatalogEntry.category.
+  category   String
+  /// Free-text licence label, e.g. "Commercial — Foundry XY". Required so
+  /// an attribution obligation can be met on the font catalogue page.
+  licence    String
+  licenceUrl String?  @map("licence_url")
+  uploadedBy String   @map("uploaded_by")
+  createdAt  DateTime @default(now()) @map("created_at")
+  updatedAt  DateTime @updatedAt @map("updated_at")
+
+  uploader User               @relation(fields: [uploadedBy], references: [id])
+  weights  CustomFontWeight[]
+
+  @@map("custom_fonts")
+}
+
+/// One weight of a custom family. Style is always `normal`: the PDF
+/// `@font-face` builder emits only that, and browsers synthesise oblique —
+/// italic uploads are a follow-up, not a silent half-feature.
+model CustomFontWeight {
+  id       String  @id @default(uuid())
+  fontId   String  @map("font_id")
+  weight   Int
+  /// Whether a legacy WOFF was supplied next to the required WOFF2.
+  hasWoff  Boolean @default(false) @map("has_woff")
+  byteSize Int     @map("byte_size")
+
+  font CustomFont @relation(fields: [fontId], references: [id], onDelete: Cascade)
+
+  @@unique([fontId, weight])
+  @@map("custom_font_weights")
+}

apps/api/scripts/gen-default-favicon.mjs

@@ -0,0 +1,127 @@
+#!/usr/bin/env node
+/**
+ * Generates the shipped default favicons (issue #306):
+ * `apps/api/assets/default-favicon-32.png` and `-180.png`.
+ *
+ * The api serves these whenever an operator has not uploaded one, so an
+ * instance always has a tab icon — the `<link rel="icon">` in index.html is
+ * static and its resource must never 404.
+ *
+ * Drawn here rather than pulled in as a binary: the whole toolchain must
+ * survive the `--network none` offline build (96-offline-build-protokoll.md),
+ * and adding an image library for one 32×32 icon would be the tail wagging
+ * the dog. Node's own zlib is enough to write a PNG.
+ *
+ * Motif: a pond seen from above — the accent-green disc with two ripples.
+ *
+ * Regenerate with `node apps/api/scripts/gen-default-favicon.mjs`, commit
+ * script and binaries together.
+ */
+import { deflateSync } from 'node:zlib';
+import { writeFileSync } from 'node:fs';
+import { dirname, join } from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+/** Brand green — the same value as index.html's light `theme-color`. */
+const GREEN = [0x2f, 0x6f, 0x4f];
+const LIGHT = [0xe8, 0xf2, 0xec];
+
+const crcTable = Array.from({ length: 256 }, (_, n) => {
+  let c = n;
+  for (let k = 0; k < 8; k += 1) c = c & 1 ? 0xedb88320 ^ (c >>> 1) : c >>> 1;
+  return c >>> 0;
+});
+
+function crc32(buf) {
+  let c = 0xffffffff;
+  for (const byte of buf) c = crcTable[(c ^ byte) & 0xff] ^ (c >>> 8);
+  return (c ^ 0xffffffff) >>> 0;
+}
+
+function chunk(type, data) {
+  const length = Buffer.alloc(4);
+  length.writeUInt32BE(data.length);
+  const body = Buffer.concat([Buffer.from(type, 'ascii'), data]);
+  const crc = Buffer.alloc(4);
+  crc.writeUInt32BE(crc32(body));
+  return Buffer.concat([length, body, crc]);
+}
+
+/** Minimal RGBA PNG writer — no filtering, one IDAT. */
+function encodePng(size, rgba) {
+  const ihdr = Buffer.alloc(13);
+  ihdr.writeUInt32BE(size, 0);
+  ihdr.writeUInt32BE(size, 4);
+  ihdr[8] = 8; // bit depth
+  ihdr[9] = 6; // colour type RGBA
+  const raw = Buffer.alloc(size * (size * 4 + 1));
+  for (let y = 0; y < size; y += 1) {
+    raw[y * (size * 4 + 1)] = 0; // filter: none
+    rgba.copy(raw, y * (size * 4 + 1) + 1, y * size * 4, (y + 1) * size * 4);
+  }
+  return Buffer.concat([
+    Buffer.from([0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a]),
+    chunk('IHDR', ihdr),
+    chunk('IDAT', deflateSync(raw, { level: 9 })),
+    chunk('IEND', Buffer.alloc(0)),
+  ]);
+}
+
+/**
+ * Colour at one point of the unit square, in continuous coordinates — the
+ * caller supersamples it, which is where the anti-aliasing comes from.
+ */
+function sample(x, y) {
+  const dx = x - 0.5;
+  const dy = y - 0.5;
+  const r = Math.hypot(dx, dy);
+  if (r > 0.48) return null; // outside the disc: transparent
+  // Two ripples spreading from a point struck slightly above centre — rings
+  // rather than a bullseye, which is why the centre stays green and the
+  // spacing widens outward the way real ripples do.
+  const rr = Math.hypot(dx, dy + 0.06);
+  const onRing = (radius, width) => Math.abs(rr - radius) < width;
+  if (onRing(0.33, 0.028) || onRing(0.19, 0.026)) return LIGHT;
+  return GREEN;
+}
+
+function render(size) {
+  const SS = 4; // supersampling factor
+  const out = Buffer.alloc(size * size * 4);
+  for (let y = 0; y < size; y += 1) {
+    for (let x = 0; x < size; x += 1) {
+      let r = 0;
+      let g = 0;
+      let b = 0;
+      let a = 0;
+      for (let sy = 0; sy < SS; sy += 1) {
+        for (let sx = 0; sx < SS; sx += 1) {
+          const c = sample((x + (sx + 0.5) / SS) / size, (y + (sy + 0.5) / SS) / size);
+          if (c) {
+            r += c[0];
+            g += c[1];
+            b += c[2];
+            a += 255;
+          }
+        }
+      }
+      const n = SS * SS;
+      const covered = a / 255;
+      const i = (y * size + x) * 4;
+      // Premultiplied average of the covered samples only, so the edge fades
+      // in alpha rather than towards black.
+      out[i] = covered ? Math.round(r / covered) : 0;
+      out[i + 1] = covered ? Math.round(g / covered) : 0;
+      out[i + 2] = covered ? Math.round(b / covered) : 0;
+      out[i + 3] = Math.round(a / n);
+    }
+  }
+  return out;
+}
+
+const assets = join(dirname(fileURLToPath(import.meta.url)), '../assets');
+for (const size of [32, 180]) {
+  const file = join(assets, `default-favicon-${size}.png`);
+  writeFileSync(file, encodePng(size, render(size)));
+  console.log(`wrote ${file}`);
+}

apps/api/src/admin/admin.controller.ts

@@ -11,9 +11,17 @@ import {
 } from '../settings/instance-settings.service';
 import { SiteAdminGuard } from './site-admin.guard';
 
-// Lifecycle markers, not configuration: never editable through this
-// endpoint (the setup lock must be irreversible, issue #80).
-const INTERNAL_KEYS: ReadonlySet<InstanceSettingKey> = new Set(['setup.completedAt']);
+// Lifecycle markers and file-backed metadata, not configuration: never
+// editable through this endpoint. The setup lock must be irreversible
+// (issue #80), and the branding entries only describe bytes on disk
+// (issue #306) — writing one by hand would claim an asset that is not
+// there. Both have their own write paths.
+const INTERNAL_KEYS: ReadonlySet<InstanceSettingKey> = new Set([
+  'setup.completedAt',
+  'instance.logo',
+  'instance.logoDark',
+  'instance.favicon',
+]);
 
 // Partial update: any subset of the known settings, each validated by
 // its own schema inside the service (double validation is fine — this

apps/api/src/admin/admin.module.ts

@@ -2,6 +2,7 @@ import { Module } from '@nestjs/common';
 
 import { AuthModule } from '../auth/auth.module';
 import { BackupModule } from '../backup/backup.module';
+import { PondsModule } from '../ponds/ponds.module';
 import { QuotasModule } from '../quotas/quotas.module';
 import { SchedulerModule } from '../scheduler/scheduler.module';
 import { SearchModule } from '../search/search.module';
@@ -19,7 +20,15 @@ import { UserAdminController } from './user-admin.controller';
 import { UserAdminService } from './user-admin.service';
 
 @Module({
-  imports: [QuotasModule, UsersModule, AuthModule, SchedulerModule, BackupModule, SearchModule],
+  imports: [
+    QuotasModule,
+    UsersModule,
+    AuthModule,
+    SchedulerModule,
+    BackupModule,
+    SearchModule,
+    PondsModule,
+  ],
   controllers: [
     AdminSettingsController,
     BackupAdminController,

apps/api/src/admin/user-admin.controller.ts

@@ -12,9 +12,11 @@ import {
   UseGuards,
 } from '@nestjs/common';
 import {
+  AdminCreateUserInput,
   AdminUserListQuery,
   AdminUserListView,
   AdminUserView,
+  adminCreateUserSchema,
   adminUserListQuerySchema,
   setSiteAdminSchema,
   setUserDisabledSchema,
@@ -31,6 +33,14 @@ import { UserAdminService } from './user-admin.service';
 export class UserAdminController {
   constructor(private readonly users: UserAdminService) {}
 
+  @Post()
+  async create(
+    @Body(new ZodValidationPipe(adminCreateUserSchema)) input: AdminCreateUserInput,
+    @Req() request: AuthedRequest,
+  ): Promise<AdminUserView> {
+    return this.users.createUser(request.user!, input);
+  }
+
   @Get()
   async list(
     @Query(new ZodValidationPipe(adminUserListQuerySchema)) query: AdminUserListQuery,

apps/api/src/admin/user-admin.e2e.db.test.ts

@@ -6,7 +6,7 @@ import { afterAll, beforeAll, describe, expect, it } from 'vitest';
 
 import { PondsService } from '../ponds/ponds.service';
 import { createTestApp, sessionCookieOf } from '../testing/test-app';
-import { createTestPrisma, hasTestDb, uniqueSuffix } from '../testing/test-db';
+import { createTestPrisma, deletePondsWhere, hasTestDb, uniqueSuffix } from '../testing/test-db';
 import { UsersService } from '../users/users.service';
 
 /**
@@ -62,13 +62,71 @@ describe.skipIf(!hasTestDb)('user admin (e2e, issue #59)', () => {
   afterAll(async () => {
     const all = Object.values(ids);
     await prisma.session.deleteMany({ where: { userId: { in: all } } });
-    await prisma.pond.deleteMany({ where: { ownerId: { in: all } } });
+    await deletePondsWhere(prisma, { ownerId: { in: all } });
     await prisma.userIdentity.deleteMany({ where: { userId: { in: all } } });
     await prisma.user.deleteMany({ where: { id: { in: all } } });
     await prisma.$disconnect();
     await app.close();
   });
 
+  it('creates an account that can log in right away, with a personal pond (issue #331)', async () => {
+    const username = `ua-created-${suffix}`;
+    const res = await api()
+      .post('/api/v1/admin/users')
+      .set('Cookie', cookies.admin1!)
+      .send({
+        username,
+        email: `${username}@example.org`,
+        displayName: 'UA Created',
+        password,
+        locale: 'de',
+      })
+      .expect(201);
+    const created = res.body as { id: string; status: string };
+    ids.created = created.id;
+    // No verification hop: the admin vouched for the address.
+    expect(created.status).toBe('ACTIVE');
+    await api()
+      .post('/api/v1/auth/login')
+      .send({ usernameOrEmail: username, password })
+      .expect(200);
+    // The personal pond exists exactly like after self-registration.
+    expect(await prisma.pond.count({ where: { ownerId: created.id, type: 'PERSONAL' } })).toBe(1);
+  });
+
+  it('rejects duplicate usernames with a field-level conflict', async () => {
+    await api()
+      .post('/api/v1/admin/users')
+      .set('Cookie', cookies.admin1!)
+      .send({
+        username: `ua-created-${suffix}`,
+        email: `ua-created-other-${suffix}@example.org`,
+        displayName: 'UA Dup',
+        password,
+        locale: 'en',
+      })
+      .expect(409)
+      .expect((r) =>
+        expect((r.body as { details: Record<string, string[]> }).details.username).toEqual([
+          'validation.taken',
+        ]),
+      );
+  });
+
+  it('refuses creation for non-admins', async () => {
+    await api()
+      .post('/api/v1/admin/users')
+      .set('Cookie', cookies.bob!)
+      .send({
+        username: `ua-sneak-${suffix}`,
+        email: `ua-sneak-${suffix}@example.org`,
+        displayName: 'UA Sneak',
+        password,
+        locale: 'en',
+      })
+      .expect(403);
+  });
+
   it('lists and searches users (Site-Admin only)', async () => {
     const res = await api()
       .get(`/api/v1/admin/users?q=ua-bob-${suffix}`)

apps/api/src/admin/user-admin.service.ts

@@ -1,5 +1,6 @@
 import { BadRequestException, Injectable, NotFoundException } from '@nestjs/common';
 import {
+  AdminCreateUserInput,
   AdminUserListQuery,
   AdminUserListView,
   AdminUserStatus,
@@ -10,7 +11,9 @@ import { PinoLogger } from 'nestjs-pino';
 
 import { AuthService } from '../auth/auth.service';
 import { AuditService } from '../audit/audit.service';
+import { PondsService } from '../ponds/ponds.service';
 import { PrismaService } from '../prisma/prisma.service';
+import { UsersService } from '../users/users.service';
 import { PseudonymizationService } from './pseudonymization.service';
 
 /**
@@ -27,12 +30,33 @@ export class UserAdminService {
     private readonly prisma: PrismaService,
     private readonly pseudonymizer: PseudonymizationService,
     private readonly auth: AuthService,
+    private readonly users: UsersService,
+    private readonly ponds: PondsService,
     private readonly audit: AuditService,
     private readonly logger: PinoLogger,
   ) {
     this.logger.setContext(UserAdminService.name);
   }
 
+  /**
+   * Creates an account on behalf of a user (issue #331). The e-mail is
+   * marked verified immediately — the admin vouches for the address — and
+   * the personal pond is provisioned exactly like the verify-email path
+   * does, so the account is indistinguishable from a self-registered one.
+   */
+  async createUser(actor: User, input: AdminCreateUserInput): Promise<AdminUserView> {
+    const user = await this.users.createUser(input);
+    const verified = await this.users.markEmailVerified(user.id);
+    await this.ponds.ensurePersonalPond(verified);
+    await this.audit.record({
+      action: 'user.created_by_admin',
+      actorId: actor.id,
+      targetType: 'user',
+      targetId: user.id,
+    });
+    return this.viewOf(verified, await this.pondCountOf(user.id));
+  }
+
   async list(query: AdminUserListQuery): Promise<AdminUserListView> {
     const q = query.q?.trim();
     const where: Prisma.UserWhereInput = q

apps/api/src/app.module.ts

@@ -6,6 +6,7 @@ import { AdminModule } from './admin/admin.module';
 import { AuditModule } from './audit/audit.module';
 import { AuthModule } from './auth/auth.module';
 import { BackupModule } from './backup/backup.module';
+import { BrandingModule } from './branding/branding.module';
 import { ApiExceptionFilter } from './common/api-exception.filter';
 import { maskTokenParam } from './common/mask-token-param';
 import { SecurityHeadersMiddleware } from './common/security-headers.middleware';
@@ -17,6 +18,7 @@ import { FilesModule } from './files/files.module';
 import { GrantsModule } from './grants/grants.module';
 import { HealthModule } from './health/health.module';
 import { HomeModule } from './home/home.module';
+import { FontsModule } from './fonts/fonts.module';
 import { ImportExportModule } from './import-export/import-export.module';
 import { LabelsModule } from './labels/labels.module';
 import { LegalModule } from './legal/legal.module';
@@ -81,6 +83,8 @@ import { VersionsModule } from './versions/versions.module';
     PublicModule,
     PublicApiModule,
     McpModule,
+    BrandingModule,
+    FontsModule,
     ImportExportModule,
     PluginsModule,
     AuthModule,

apps/api/src/audit/audit-actions.ts

@@ -29,6 +29,9 @@ export const AUDIT_EVENTS = {
   'file.integrity_failed': { severity: 'critical' },
   'grant.created': { severity: 'notice' },
   'grant.deleted': { severity: 'notice' },
+  'invitation.accepted': { severity: 'notice' },
+  'invitation.created': { severity: 'info' },
+  'invitation.revoked': { severity: 'info' },
   'job.triggered': { severity: 'info' },
   'member.added': { severity: 'notice' },
   'member.removed': { severity: 'notice' },
@@ -36,18 +39,24 @@ export const AUDIT_EVENTS = {
   'page.classification_lowered': { severity: 'warning' },
   'page.classification_raised': { severity: 'notice' },
   'plugin.installed': { severity: 'notice' },
+  'plugin.rejected': { severity: 'warning' },
   'plugin.mode_set': { severity: 'notice' },
   'plugin.pond_toggled': { severity: 'info' },
   'plugin.uninstalled': { severity: 'notice' },
+  'pond.archived': { severity: 'notice' },
   'pond.purged': { severity: 'notice' },
   'quota.override_cleared': { severity: 'notice' },
   'quota.override_set': { severity: 'notice' },
   'read_trail.pruned': { severity: 'info' },
   'settings.changed': { severity: 'notice' },
+  'branding.changed': { severity: 'notice' },
+  'font.uploaded': { severity: 'notice' },
+  'font.deleted': { severity: 'notice' },
   'setup.admin_created': { severity: 'notice' },
   'setup.completed': { severity: 'info' },
   'setup.preseeded': { severity: 'info' },
   'setup.smtp_stored': { severity: 'info' },
+  'user.created_by_admin': { severity: 'notice' },
   'user.deleted': { severity: 'notice' },
   'user.disabled_set': { severity: 'notice' },
   'user.pseudonymized': { severity: 'notice' },

apps/api/src/auth/auth.e2e.db.test.ts

@@ -4,7 +4,7 @@ import request from 'supertest';
 import { afterAll, beforeAll, describe, expect, it } from 'vitest';
 
 import { createTestApp, sessionCookieOf } from '../testing/test-app';
-import { createTestPrisma, hasTestDb, uniqueSuffix } from '../testing/test-db';
+import { createTestPrisma, deletePondsWhere, hasTestDb, uniqueSuffix } from '../testing/test-db';
 
 describe.skipIf(!hasTestDb)('auth flows (e2e)', () => {
   let app: INestApplication;
@@ -46,7 +46,7 @@ describe.skipIf(!hasTestDb)('auth flows (e2e)', () => {
 
   afterAll(async () => {
     // Verified users own a personal pond (#21) — remove it before them.
-    await prisma.pond.deleteMany({ where: { owner: { username: { contains: suffix } } } });
+    await deletePondsWhere(prisma, { owner: { username: { contains: suffix } } });
     await prisma.user.deleteMany({ where: { username: { contains: suffix } } });
     await prisma.mailOutbox.deleteMany({ where: { toAddress: { contains: suffix } } });
     await prisma.$disconnect();

apps/api/src/auth/auth.module.ts

@@ -3,6 +3,7 @@ import { APP_GUARD } from '@nestjs/core';
 
 import { AppConfig } from '../config/app-config.service';
 import { GrantsModule } from '../grants/grants.module';
+import { InvitationsModule } from '../invitations/invitations.module';
 
 import { MailModule } from '../mail/mail.module';
 import { PondsModule } from '../ponds/ponds.module';
@@ -18,7 +19,7 @@ import { ProxyIdentityService } from './proxy-identity.service';
 import { SessionsModule } from './sessions.module';
 
 @Module({
-  imports: [UsersModule, MailModule, SessionsModule, PondsModule, GrantsModule],
+  imports: [UsersModule, MailModule, SessionsModule, PondsModule, GrantsModule, InvitationsModule],
   controllers: [AuthController, OidcController],
   providers: [
     AuthService,

apps/api/src/auth/auth.service.ts

@@ -9,6 +9,7 @@ import { User } from '@prisma/client';
 import { PinoLogger } from 'nestjs-pino';
 
 import { AppConfig } from '../config/app-config.service';
+import { InvitationsService } from '../invitations/invitations.service';
 import { MailService } from '../mail/mail.service';
 import { PondsService } from '../ponds/ponds.service';
 import { AuditService } from '../audit/audit.service';
@@ -33,6 +34,7 @@ export class AuthService {
     private readonly sessions: SessionsService,
     private readonly mail: MailService,
     private readonly ponds: PondsService,
+    private readonly invitations: InvitationsService,
     private readonly rateLimits: RateLimitService,
     private readonly audit: AuditService,
     private readonly config: AppConfig,
@@ -43,10 +45,37 @@ export class AuthService {
   }
 
   async signup(input: SignupInput): Promise<void> {
-    if ((await this.settings.get('auth.registrationMode')) === 'closed') {
+    // An invitation token (issue #332) lets exactly one signup through a
+    // closed registration. Claimed atomically BEFORE the account exists;
+    // rolled back if the signup fails (duplicate username), so the invitee
+    // can retry with the same link.
+    const invitation = input.invitationToken
+      ? await this.invitations.redeem(input.invitationToken)
+      : null;
+    if (input.invitationToken && !invitation) {
+      throw new BadRequestException({ code: 'token_invalid' });
+    }
+    if (!invitation && (await this.settings.get('auth.registrationMode')) === 'closed') {
       throw new ForbiddenException({ code: 'registration_closed' });
     }
-    const user = await this.users.createUser(input);
+    let user: User;
+    try {
+      user = await this.users.createUser(input);
+    } catch (error) {
+      if (invitation) await this.invitations.unredeem(invitation.id);
+      throw error;
+    }
+    if (invitation) {
+      await this.invitations.markAccepted(invitation.id, user.id);
+      await this.audit.record({
+        action: 'invitation.accepted',
+        actorId: user.id,
+        targetType: 'invitation',
+        targetId: invitation.id,
+      });
+    }
+    // The invite link proves nothing about the mailbox (it can be
+    // forwarded), so the usual verification mail still applies.
     await this.sendVerificationMail(user);
     await this.audit.record({ action: 'auth.signup', actorId: user.id });
   }

apps/api/src/branding/branding-storage.service.ts

@@ -0,0 +1,50 @@
+import { mkdir, readFile, rm, writeFile } from 'node:fs/promises';
+import { join } from 'node:path';
+
+import { Injectable } from '@nestjs/common';
+
+import { AppConfig } from '../config/app-config.service';
+
+/**
+ * Filesystem binding for branding assets (issue #306; pond overrides #307).
+ *
+ * One flat directory of PNGs named by a caller-supplied key
+ * (`instance-logo-light`, later `pond-<id>-favicon-32`). Flat because there
+ * are a handful of files per instance and the backup archives the directory
+ * as a whole — a tree would buy nothing and cost a traversal question.
+ *
+ * The key is constrained here rather than trusted from the route: it is the
+ * only thing between a request parameter and a path.
+ */
+@Injectable()
+export class BrandingStorageService {
+  constructor(private readonly config: AppConfig) {}
+
+  /** Lowercase, digits and dashes only — no dot, so no `..`, and no slash,
+   *  so the file cannot leave the directory whatever a caller sends. */
+  private pathFor(key: string): string {
+    if (!/^[a-z0-9-]{1,120}$/.test(key)) throw new Error(`invalid branding key: ${key}`);
+    return join(this.config.env.BRANDING_DIR, `${key}.png`);
+  }
+
+  async save(key: string, bytes: Buffer): Promise<void> {
+    await mkdir(this.config.env.BRANDING_DIR, { recursive: true });
+    await writeFile(this.pathFor(key), bytes);
+  }
+
+  /** The bytes, or null when the file is absent — a missing asset is a normal
+   *  state here (nothing uploaded, or metadata and disk drifted after a
+   *  partial restore), and every caller has a fallback. */
+  async read(key: string): Promise<Buffer | null> {
+    try {
+      return await readFile(this.pathFor(key));
+    } catch {
+      return null;
+    }
+  }
+
+  /** Idempotent: removing what is not there is success. */
+  async remove(key: string): Promise<void> {
+    await rm(this.pathFor(key), { force: true });
+  }
+}

apps/api/src/branding/branding.controller.ts

@@ -0,0 +1,253 @@
+import {
+  BadRequestException,
+  Controller,
+  Delete,
+  Get,
+  NotFoundException,
+  Param,
+  Post,
+  Query,
+  Req,
+  Res,
+  UploadedFiles,
+  UseGuards,
+  UseInterceptors,
+} from '@nestjs/common';
+import { AnyFilesInterceptor } from '@nestjs/platform-express';
+import {
+  BrandingView,
+  FAVICON_SIZES,
+  FaviconSize,
+  LOGO_VARIANTS,
+  LogoVariant,
+  MAX_BRANDING_BYTES,
+  PondBranding,
+} from '@dorfteich/shared';
+import type { Response } from 'express';
+
+import { SiteAdminGuard } from '../admin/site-admin.guard';
+import { AuthedRequest, Public } from '../auth/auth.guard';
+import { RequiresPondRole } from '../permissions/permission.decorators';
+import { PrismaService } from '../prisma/prisma.service';
+import { BrandingService } from './branding.service';
+
+function parseVariant(value: unknown): LogoVariant {
+  if (!LOGO_VARIANTS.includes(value as LogoVariant)) {
+    throw new BadRequestException({ code: 'bad_request' });
+  }
+  return value as LogoVariant;
+}
+
+/**
+ * Public branding surface (issue #306).
+ *
+ * Unauthenticated by design and worth stating plainly in the admin UI: the
+ * login screen carries the branding and the browser fetches the favicon before
+ * anyone signs in, so an operator's logo IS visible to anonymous visitors.
+ */
+@Controller('branding')
+export class BrandingController {
+  constructor(private readonly branding: BrandingService) {}
+
+  @Public()
+  @Get()
+  view(): Promise<BrandingView> {
+    return this.branding.view();
+  }
+
+  @Public()
+  @Get('logo')
+  async logo(
+    @Query('variant') variant: string | undefined,
+    @Query('pond') pondId: string | undefined,
+    @Res() res: Response,
+  ): Promise<void> {
+    const wanted = parseVariant(variant ?? 'light');
+    // A pond scope serves the pond's own bytes and nothing else: the caller
+    // already resolved WHICH level applies (`resolveBranding`), so silently
+    // falling back here would mix variants across levels — exactly what #307
+    // forbids.
+    const bytes = pondId
+      ? await this.branding.pondLogoBytes(pondId, wanted)
+      : await this.branding.logoBytes(wanted);
+    // No shipped default: without a logo the app renders the instance NAME as
+    // text, so an empty answer here is the honest one.
+    if (!bytes) {
+      res.status(404).json({ code: 'not_found', message: 'no logo' });
+      return;
+    }
+    res.setHeader('Content-Type', 'image/png');
+    // The caller puts the content hash in the query string, so a given URL
+    // never changes what it points at.
+    res.setHeader('Cache-Control', 'public, max-age=31536000, immutable');
+    res.send(bytes);
+  }
+
+  @Public()
+  @Get('favicon')
+  async favicon(
+    @Query('size') size: string | undefined,
+    @Query('pond') pondId: string | undefined,
+    @Res() res: Response,
+  ): Promise<void> {
+    const wanted = Number(size ?? 32);
+    if (!(FAVICON_SIZES as readonly number[]).includes(wanted)) {
+      throw new BadRequestException({ code: 'bad_request' });
+    }
+    const pondBytes = pondId
+      ? await this.branding.pondFaviconBytes(pondId, wanted as FaviconSize)
+      : null;
+    const { bytes, uploaded } = pondBytes
+      ? { bytes: pondBytes, uploaded: true }
+      : await this.branding.faviconBytes(wanted as FaviconSize);
+    res.setHeader('Content-Type', 'image/png');
+    // The `<link rel="icon">` href is a constant in index.html, so this URL
+    // cannot carry a hash — revalidation is the only way a replaced favicon
+    // ever reaches a browser that already has one.
+    res.setHeader('Cache-Control', 'no-cache');
+    res.setHeader('ETag', `"${uploaded ? 'custom' : 'default'}-${bytes.length}"`);
+    res.send(bytes);
+  }
+}
+
+/** Site-Admin management of the instance branding (issue #306). */
+@Controller('admin/branding')
+@UseGuards(SiteAdminGuard)
+export class BrandingAdminController {
+  constructor(private readonly branding: BrandingService) {}
+
+  @Post('logo')
+  @UseInterceptors(AnyFilesInterceptor({ limits: { fileSize: MAX_BRANDING_BYTES } }))
+  async setLogo(
+    @Query('variant') variant: string | undefined,
+    @Req() request: AuthedRequest,
+    @UploadedFiles() files: Express.Multer.File[] | undefined,
+  ): Promise<BrandingView> {
+    const file = files?.find((entry) => entry.fieldname === 'file');
+    if (!file) throw new BadRequestException({ code: 'branding_file_missing' });
+    return this.branding.setLogo(request.user!, parseVariant(variant ?? 'light'), file.buffer);
+  }
+
+  @Delete('logo')
+  clearLogo(
+    @Query('variant') variant: string | undefined,
+    @Req() request: AuthedRequest,
+  ): Promise<BrandingView> {
+    return this.branding.clearLogo(request.user!, parseVariant(variant ?? 'light'));
+  }
+
+  @Post('favicon')
+  @UseInterceptors(AnyFilesInterceptor({ limits: { fileSize: MAX_BRANDING_BYTES } }))
+  async setFavicon(
+    @Req() request: AuthedRequest,
+    @UploadedFiles() files: Express.Multer.File[] | undefined,
+  ): Promise<BrandingView> {
+    // Field names are the pixel sizes the browser rendered: `png-32`, `png-180`.
+    const byField = new Map((files ?? []).map((file) => [file.fieldname, file.buffer]));
+    const collected = {} as Record<FaviconSize, Buffer>;
+    for (const size of FAVICON_SIZES) {
+      const bytes = byField.get(`png-${size}`);
+      if (!bytes) throw new BadRequestException({ code: 'branding_file_missing' });
+      collected[size] = bytes;
+    }
+    return this.branding.setFavicon(request.user!, collected);
+  }
+
+  @Delete('favicon')
+  clearFavicon(@Req() request: AuthedRequest): Promise<BrandingView> {
+    return this.branding.clearFavicon(request.user!);
+  }
+}
+
+/**
+ * Pond-level branding (issue #307). The uploader here is an ordinary Pond
+ * Admin rather than the operator, so the security rules of #306 are not
+ * relaxed by a single line: SVG refused, magic bytes checked server-side,
+ * size caps enforced, content type pinned on serving, no image parsing.
+ *
+ * 404/403 policy: a user who cannot see the pond gets 404 from the pond-role
+ * guard, one who can see but not administer it gets 403.
+ */
+@Controller('ponds/:pondId/branding')
+export class PondBrandingController {
+  constructor(
+    private readonly branding: BrandingService,
+    private readonly prisma: PrismaService,
+  ) {}
+
+  /** The pond row the quota is charged to. */
+  private async pondOf(pondId: string): Promise<{ id: string; ownerId: string }> {
+    const pond = await this.prisma.pond.findUnique({
+      where: { id: pondId },
+      select: { id: true, ownerId: true },
+    });
+    if (!pond) throw new NotFoundException();
+    return pond;
+  }
+
+  @Get()
+  @RequiresPondRole('reader', { idParam: 'pondId' })
+  view(@Param('pondId') pondId: string): Promise<PondBranding> {
+    return this.branding.pondBranding(pondId);
+  }
+
+  @Post('logo')
+  @RequiresPondRole('pond_admin', { idParam: 'pondId' })
+  @UseInterceptors(AnyFilesInterceptor({ limits: { fileSize: MAX_BRANDING_BYTES } }))
+  async setLogo(
+    @Param('pondId') pondId: string,
+    @Query('variant') variant: string | undefined,
+    @Req() request: AuthedRequest,
+    @UploadedFiles() files: Express.Multer.File[] | undefined,
+  ): Promise<PondBranding> {
+    const file = files?.find((entry) => entry.fieldname === 'file');
+    if (!file) throw new BadRequestException({ code: 'branding_file_missing' });
+    return this.branding.setPondLogo(
+      request.user!,
+      await this.pondOf(pondId),
+      parseVariant(variant ?? 'light'),
+      file.buffer,
+    );
+  }
+
+  @Delete('logo')
+  @RequiresPondRole('pond_admin', { idParam: 'pondId' })
+  async clearLogo(
+    @Param('pondId') pondId: string,
+    @Query('variant') variant: string | undefined,
+    @Req() request: AuthedRequest,
+  ): Promise<PondBranding> {
+    return this.branding.clearPondLogo(
+      request.user!,
+      await this.pondOf(pondId),
+      parseVariant(variant ?? 'light'),
+    );
+  }
+
+  @Post('favicon')
+  @RequiresPondRole('pond_admin', { idParam: 'pondId' })
+  @UseInterceptors(AnyFilesInterceptor({ limits: { fileSize: MAX_BRANDING_BYTES } }))
+  async setFavicon(
+    @Param('pondId') pondId: string,
+    @Req() request: AuthedRequest,
+    @UploadedFiles() files: Express.Multer.File[] | undefined,
+  ): Promise<PondBranding> {
+    const byField = new Map((files ?? []).map((file) => [file.fieldname, file.buffer]));
+    const collected = {} as Record<FaviconSize, Buffer>;
+    for (const size of FAVICON_SIZES) {
+      const bytes = byField.get(`png-${size}`);
+      if (!bytes) throw new BadRequestException({ code: 'branding_file_missing' });
+      collected[size] = bytes;
+    }
+    return this.branding.setPondFavicon(request.user!, await this.pondOf(pondId), collected);
+  }
+
+  @Delete('favicon')
+  @RequiresPondRole('pond_admin', { idParam: 'pondId' })
+  async clearFavicon(
+    @Param('pondId') pondId: string,
+    @Req() request: AuthedRequest,
+  ): Promise<PondBranding> {
+    return this.branding.clearPondFavicon(request.user!, await this.pondOf(pondId));
+  }
+}

apps/api/src/branding/branding.e2e.db.test.ts

@@ -0,0 +1,250 @@
+import { mkdtemp, readFile, rm } from 'node:fs/promises';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+
+import { INestApplication } from '@nestjs/common';
+import { PrismaClient } from '@prisma/client';
+import request from 'supertest';
+import { afterAll, beforeAll, describe, expect, it } from 'vitest';
+
+import { createTestApp, sessionCookieOf } from '../testing/test-app';
+import { createTestPrisma, hasTestDb, uniqueSuffix } from '../testing/test-db';
+import { UsersService } from '../users/users.service';
+
+/**
+ * A real PNG of `size`×`size`, built the same way the shipped default is —
+ * the api reads the IHDR, so the header has to be genuine.
+ */
+async function png(size: number): Promise<Buffer> {
+  const { deflateSync } = await import('node:zlib');
+  const crcTable = Array.from({ length: 256 }, (_, n) => {
+    let c = n;
+    for (let k = 0; k < 8; k += 1) c = c & 1 ? 0xedb88320 ^ (c >>> 1) : c >>> 1;
+    return c >>> 0;
+  });
+  const crc32 = (buf: Buffer): number => {
+    let c = 0xffffffff;
+    for (const byte of buf) c = crcTable[(c ^ byte) & 0xff]! ^ (c >>> 8);
+    return (c ^ 0xffffffff) >>> 0;
+  };
+  const chunk = (type: string, data: Buffer): Buffer => {
+    const length = Buffer.alloc(4);
+    length.writeUInt32BE(data.length);
+    const body = Buffer.concat([Buffer.from(type, 'ascii'), data]);
+    const crc = Buffer.alloc(4);
+    crc.writeUInt32BE(crc32(body));
+    return Buffer.concat([length, body, crc]);
+  };
+  const ihdr = Buffer.alloc(13);
+  ihdr.writeUInt32BE(size, 0);
+  ihdr.writeUInt32BE(size, 4);
+  ihdr[8] = 8;
+  ihdr[9] = 6;
+  const raw = Buffer.alloc(size * (size * 4 + 1));
+  return Buffer.concat([
+    Buffer.from([0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a]),
+    chunk('IHDR', ihdr),
+    chunk('IDAT', deflateSync(raw)),
+    chunk('IEND', Buffer.alloc(0)),
+  ]);
+}
+
+describe.skipIf(!hasTestDb)('instance branding (e2e, issue #306)', () => {
+  let app: INestApplication;
+  let prisma: PrismaClient;
+  let brandingDir: string;
+  const suffix = uniqueSuffix();
+  const password = 'markenzeichen mit teich 1';
+  const admin = { username: `ba-${suffix}` };
+  const plain = { username: `bp-${suffix}` };
+  let adminCookie: string;
+  let plainCookie: string;
+
+  const api = () => request(app.getHttpServer());
+
+  beforeAll(async () => {
+    prisma = createTestPrisma();
+    await prisma.rateLimit.deleteMany({});
+    // A real directory: the point is that bytes land somewhere and come back.
+    brandingDir = await mkdtemp(join(tmpdir(), 'dorfteich-branding-'));
+    process.env.BRANDING_DIR = brandingDir;
+    app = await createTestApp();
+    const users = app.get(UsersService);
+
+    const adminUser = await users.createUser({
+      username: admin.username,
+      email: `${admin.username}@example.org`,
+      displayName: `Branding Admin ${suffix}`,
+      password,
+      locale: 'en',
+    });
+    await users.markEmailVerified(adminUser.id);
+    await prisma.user.update({ where: { id: adminUser.id }, data: { isSiteAdmin: true } });
+
+    const plainUser = await users.createUser({
+      username: plain.username,
+      email: `${plain.username}@example.org`,
+      displayName: `Branding Plain ${suffix}`,
+      password,
+      locale: 'en',
+    });
+    await users.markEmailVerified(plainUser.id);
+
+    const login = async (username: string): Promise<string> =>
+      sessionCookieOf(
+        await api()
+          .post('/api/v1/auth/login')
+          .send({ usernameOrEmail: username, password })
+          .expect(200),
+      );
+    adminCookie = await login(admin.username);
+    plainCookie = await login(plain.username);
+  });
+
+  afterAll(async () => {
+    await prisma.instanceSetting.deleteMany({
+      where: { key: { in: ['instance.logo', 'instance.logoDark', 'instance.favicon'] } },
+    });
+    await prisma.user.deleteMany({ where: { username: { contains: suffix } } });
+    await prisma.$disconnect();
+    await app.close();
+    await rm(brandingDir, { recursive: true, force: true });
+    delete process.env.BRANDING_DIR;
+  });
+
+  it('serves the shipped default favicon before anything is uploaded', async () => {
+    // The `<link rel="icon">` in index.html is a constant — this route must
+    // never 404, or the browser keeps its generic icon for good.
+    const res = await api().get('/api/v1/branding/favicon').expect(200);
+    expect(res.headers['content-type']).toContain('image/png');
+    expect(res.body.subarray(0, 8).toString('latin1')).toContain('PNG');
+  });
+
+  it('stores a logo, reports it, and serves the bytes without a session', async () => {
+    const bytes = await png(64);
+    const view = await api()
+      .post('/api/v1/admin/branding/logo?variant=light')
+      .set('Cookie', adminCookie)
+      .attach('file', bytes, 'logo.png')
+      .expect(201);
+    expect(view.body.logo).toMatchObject({ width: 64, height: 64 });
+    expect(view.body.logoDark).toBeNull();
+
+    // On disk, under the key the pond override (#307) will extend.
+    const onDisk = await readFile(join(brandingDir, 'instance-logo-light.png'));
+    expect(onDisk.length).toBe(bytes.length);
+
+    // Anonymous: the login screen carries the branding.
+    const served = await api().get('/api/v1/branding/logo?variant=light').expect(200);
+    expect(served.headers['content-type']).toContain('image/png');
+    const anon = await api().get('/api/v1/branding').expect(200);
+    expect(anon.body.logo.hash).toBe(view.body.logo.hash);
+    expect(anon.body.instanceName).toBeTruthy();
+  });
+
+  it('answers 404 for a logo variant that was never uploaded', async () => {
+    // No shipped default for the logo: without one the app renders the
+    // instance NAME, so an empty answer is the honest one.
+    await api().get('/api/v1/branding/logo?variant=dark').expect(404);
+  });
+
+  it('rejects an SVG with its own message, not a generic one', async () => {
+    const res = await api()
+      .post('/api/v1/admin/branding/logo?variant=light')
+      .set('Cookie', adminCookie)
+      .attach('file', Buffer.from('<?xml version="1.0"?><svg xmlns="..."><script/></svg>'), 'x.png')
+      .expect(400);
+    expect(res.body.code).toBe('branding_svg_rejected');
+  });
+
+  it('rejects bytes that are not a PNG at all', async () => {
+    const res = await api()
+      .post('/api/v1/admin/branding/logo?variant=light')
+      .set('Cookie', adminCookie)
+      .attach('file', Buffer.from('GIF89a and then some'), 'x.png')
+      .expect(400);
+    expect(res.body.code).toBe('branding_not_a_png');
+  });
+
+  it('rejects a logo larger than the maximum edge', async () => {
+    const res = await api()
+      .post('/api/v1/admin/branding/logo?variant=light')
+      .set('Cookie', adminCookie)
+      .attach('file', await png(600), 'x.png')
+      .expect(400);
+    expect(res.body.code).toBe('branding_image_too_large');
+  });
+
+  it('takes both favicon sizes together and serves each back', async () => {
+    await api()
+      .post('/api/v1/admin/branding/favicon')
+      .set('Cookie', adminCookie)
+      .attach('png-32', await png(32), 'f32.png')
+      .attach('png-180', await png(180), 'f180.png')
+      .expect(201);
+
+    for (const size of [32, 180]) {
+      const res = await api().get(`/api/v1/branding/favicon?size=${size}`).expect(200);
+      expect(res.body.length).toBe((await png(size)).length);
+    }
+  });
+
+  it('refuses a favicon whose bytes do not match the size they claim', async () => {
+    const res = await api()
+      .post('/api/v1/admin/branding/favicon')
+      .set('Cookie', adminCookie)
+      .attach('png-32', await png(64), 'f32.png')
+      .attach('png-180', await png(180), 'f180.png')
+      .expect(400);
+    expect(res.body.code).toBe('branding_favicon_not_square');
+  });
+
+  it('clears an asset and falls back again', async () => {
+    await api().delete('/api/v1/admin/branding/favicon').set('Cookie', adminCookie).expect(200);
+    const view = await api().get('/api/v1/branding').expect(200);
+    expect(view.body.favicon).toBeNull();
+    // Back to the shipped default rather than a 404.
+    await api().get('/api/v1/branding/favicon').expect(200);
+
+    await api()
+      .delete('/api/v1/admin/branding/logo?variant=light')
+      .set('Cookie', adminCookie)
+      .expect(200);
+    await api().get('/api/v1/branding/logo?variant=light').expect(404);
+  });
+
+  it('keeps management away from a non-admin, but not reading', async () => {
+    await api()
+      .post('/api/v1/admin/branding/logo?variant=light')
+      .set('Cookie', plainCookie)
+      .attach('file', await png(32), 'x.png')
+      .expect(403);
+    await api().delete('/api/v1/admin/branding/favicon').set('Cookie', plainCookie).expect(403);
+    await api().get('/api/v1/branding').set('Cookie', plainCookie).expect(200);
+  });
+
+  it('audits every branding change with scope, asset and direction', async () => {
+    await api()
+      .post('/api/v1/admin/branding/logo?variant=dark')
+      .set('Cookie', adminCookie)
+      .attach('file', await png(48), 'logo.png')
+      .expect(201);
+    const entry = await prisma.auditEntry.findFirst({
+      where: { action: 'branding.changed', targetId: 'instance.logoDark' },
+      orderBy: { at: 'desc' },
+    });
+    expect(entry).not.toBeNull();
+    expect(entry!.details).toMatchObject({ scope: 'instance', asset: 'logoDark', change: 'set' });
+  });
+
+  it('refuses to write branding metadata through the settings endpoint', async () => {
+    // The metadata describes bytes on disk; hand-writing it would claim an
+    // asset that is not there, so the settings PATCH does not accept it.
+    const res = await api()
+      .patch('/api/v1/admin/settings')
+      .set('Cookie', adminCookie)
+      .send({ 'instance.logo': { hash: 'deadbeefdeadbeef', width: 10, height: 10 } })
+      .expect(400);
+    expect(res.body.code).toBe('bad_request');
+  });
+});

apps/api/src/branding/branding.module.ts

@@ -0,0 +1,23 @@
+import { Module } from '@nestjs/common';
+
+import { PermissionsModule } from '../permissions/permissions.module';
+import { QuotasModule } from '../quotas/quotas.module';
+
+import {
+  BrandingAdminController,
+  BrandingController,
+  PondBrandingController,
+} from './branding.controller';
+import { BrandingStorageService } from './branding-storage.service';
+import { BrandingService } from './branding.service';
+
+/** Instance branding — logo and favicon (issue #306). Exports the services so
+ * the pond-level override (#307) can build on the same storage and the same
+ * resolution path instead of a parallel one. */
+@Module({
+  imports: [PermissionsModule, QuotasModule],
+  controllers: [BrandingController, BrandingAdminController, PondBrandingController],
+  providers: [BrandingService, BrandingStorageService],
+  exports: [BrandingService, BrandingStorageService],
+})
+export class BrandingModule {}

apps/api/src/branding/branding.service.ts

@@ -0,0 +1,380 @@
+import { createHash } from 'node:crypto';
+import { readFile } from 'node:fs/promises';
+import { join } from 'node:path';
+
+import { BadRequestException, Injectable, NotFoundException } from '@nestjs/common';
+import {
+  BrandingAsset,
+  BrandingView,
+  FAVICON_SIZES,
+  FaviconSize,
+  LOGO_VARIANTS,
+  LogoVariant,
+  PondBranding,
+  pondSettingsSchema,
+  MAX_BRANDING_BYTES,
+  MAX_LOGO_EDGE,
+  hasPngMagic,
+  looksLikeSvg,
+  pngDimensions,
+} from '@dorfteich/shared';
+import { User } from '@prisma/client';
+
+import { AuditService } from '../audit/audit.service';
+import { PrismaService } from '../prisma/prisma.service';
+import { QuotaService } from '../quotas/quota.service';
+import { InstanceSettingsService } from '../settings/instance-settings.service';
+import { BrandingStorageService } from './branding-storage.service';
+
+/** The settings key each instance asset's metadata lives under. */
+const INSTANCE_KEYS = {
+  logoLight: 'instance.logo',
+  logoDark: 'instance.logoDark',
+  favicon: 'instance.favicon',
+} as const;
+
+/**
+ * Instance branding (issue #306): the logo shown at the top of the sidebar and
+ * the favicon served to the browser.
+ *
+ * The api stores and serves bytes; it never decodes them. Validation is the
+ * PNG signature, the IHDR dimensions and the size cap — see
+ * `packages/shared/src/branding.ts` for why that line is drawn there.
+ */
+@Injectable()
+export class BrandingService {
+  constructor(
+    private readonly settings: InstanceSettingsService,
+    private readonly storage: BrandingStorageService,
+    private readonly audit: AuditService,
+    private readonly prisma: PrismaService,
+    private readonly quotas: QuotaService,
+  ) {}
+
+  static logoKey(variant: LogoVariant): string {
+    return `instance-logo-${variant}`;
+  }
+
+  static faviconKey(size: FaviconSize): string {
+    return `instance-favicon-${size}`;
+  }
+
+  /** Pond assets share the directory and the naming rules (issue #307); the
+   *  pond id keeps them apart and makes purge a prefix delete. */
+  static pondLogoKey(pondId: string, variant: LogoVariant): string {
+    return `pond-${pondId}-logo-${variant}`;
+  }
+
+  static pondFaviconKey(pondId: string, size: FaviconSize): string {
+    return `pond-${pondId}-favicon-${size}`;
+  }
+
+  /** Every branding file a pond can own — the purge deletes exactly this set
+   *  (issue #307). The purge standard is absolute: after it, nothing
+   *  referencing the pond survives, rows or files. */
+  static pondKeys(pondId: string): string[] {
+    return [
+      ...LOGO_VARIANTS.map((variant) => BrandingService.pondLogoKey(pondId, variant)),
+      ...FAVICON_SIZES.map((size) => BrandingService.pondFaviconKey(pondId, size)),
+    ];
+  }
+
+  /**
+   * Rejects anything that is not a PNG within the caps, before a byte is
+   * written. SVG gets its own message: an operator who tried one deserves to
+   * learn that it is refused on purpose, not that "the file is broken".
+   */
+  private assertUsablePng(bytes: Buffer, maxEdge: number): { width: number; height: number } {
+    if (bytes.length === 0) throw new BadRequestException({ code: 'branding_file_empty' });
+    if (bytes.length > MAX_BRANDING_BYTES) {
+      throw new BadRequestException({ code: 'branding_file_too_large' });
+    }
+    if (looksLikeSvg(bytes)) throw new BadRequestException({ code: 'branding_svg_rejected' });
+    if (!hasPngMagic(bytes)) throw new BadRequestException({ code: 'branding_not_a_png' });
+    const size = pngDimensions(bytes);
+    if (!size) throw new BadRequestException({ code: 'branding_not_a_png' });
+    if (size.width > maxEdge || size.height > maxEdge) {
+      throw new BadRequestException({ code: 'branding_image_too_large' });
+    }
+    return size;
+  }
+
+  /**
+   * Reserve the pond's storage for a branding asset, releasing what the asset
+   * it replaces occupied. Doing it in that order means replacing a logo with
+   * one of the same size costs nothing — otherwise every re-upload would eat
+   * the quota again, which is how "a pond admin fills the disk with logos"
+   * happens.
+   */
+  private async chargeQuota(
+    pond: { id: string; ownerId: string },
+    bytes: number,
+    previous: BrandingAsset | null,
+  ): Promise<void> {
+    if (previous?.byteSize) await this.quotas.release(pond.id, previous.byteSize);
+    try {
+      await this.quotas.checkAndConsume(pond.id, pond.ownerId, bytes);
+    } catch (error) {
+      // Put the released reservation back: a refused upload must not leave
+      // the pond with MORE room than before.
+      if (previous?.byteSize) {
+        await this.quotas.checkAndConsume(pond.id, pond.ownerId, previous.byteSize);
+      }
+      throw error;
+    }
+  }
+
+  private assetOf(bytes: Buffer, size: { width: number; height: number }): BrandingAsset {
+    return {
+      // Short digest: it only has to change when the bytes change, and it
+      // travels in every logo URL.
+      hash: createHash('sha256').update(bytes).digest('hex').slice(0, 16),
+      byteSize: bytes.length,
+      ...size,
+    };
+  }
+
+  async view(): Promise<BrandingView> {
+    const [logo, logoDark, favicon, instanceName] = await Promise.all([
+      this.settings.get(INSTANCE_KEYS.logoLight),
+      this.settings.get(INSTANCE_KEYS.logoDark),
+      this.settings.get(INSTANCE_KEYS.favicon),
+      this.settings.get('instance.name'),
+    ]);
+    return { logo, logoDark, favicon, instanceName };
+  }
+
+  async setLogo(admin: User, variant: LogoVariant, bytes: Buffer): Promise<BrandingView> {
+    const size = this.assertUsablePng(bytes, MAX_LOGO_EDGE);
+    await this.storage.save(BrandingService.logoKey(variant), bytes);
+    await this.settings.set(
+      variant === 'dark' ? INSTANCE_KEYS.logoDark : INSTANCE_KEYS.logoLight,
+      this.assetOf(bytes, size),
+      admin.id,
+    );
+    await this.record(admin, variant === 'dark' ? 'logoDark' : 'logo', 'set');
+    return this.view();
+  }
+
+  async clearLogo(admin: User, variant: LogoVariant): Promise<BrandingView> {
+    await this.storage.remove(BrandingService.logoKey(variant));
+    await this.settings.set(
+      variant === 'dark' ? INSTANCE_KEYS.logoDark : INSTANCE_KEYS.logoLight,
+      null,
+      admin.id,
+    );
+    await this.record(admin, variant === 'dark' ? 'logoDark' : 'logo', 'cleared');
+    return this.view();
+  }
+
+  /**
+   * Both favicon sizes arrive together: the browser produced them from one
+   * source on the same canvas, and the api cannot resize. Storing them as a
+   * pair keeps the tab icon and the home-screen icon from ever showing two
+   * different images.
+   */
+  async setFavicon(admin: User, files: Record<FaviconSize, Buffer>): Promise<BrandingView> {
+    const sizes = Object.entries(files).map(([declared, bytes]) => {
+      const size = this.assertUsablePng(bytes, 512);
+      const expected = Number(declared);
+      if (size.width !== expected || size.height !== expected) {
+        throw new BadRequestException({ code: 'branding_favicon_not_square' });
+      }
+      return { expected: expected as FaviconSize, bytes, size };
+    });
+    for (const entry of sizes) {
+      await this.storage.save(BrandingService.faviconKey(entry.expected), entry.bytes);
+    }
+    // The 32px variant identifies the pair — it is what the tab shows.
+    const small = sizes.find((entry) => entry.expected === 32)!;
+    await this.settings.set(INSTANCE_KEYS.favicon, this.assetOf(small.bytes, small.size), admin.id);
+    await this.record(admin, 'favicon', 'set');
+    return this.view();
+  }
+
+  async clearFavicon(admin: User): Promise<BrandingView> {
+    await this.storage.remove(BrandingService.faviconKey(32));
+    await this.storage.remove(BrandingService.faviconKey(180));
+    await this.settings.set(INSTANCE_KEYS.favicon, null, admin.id);
+    await this.record(admin, 'favicon', 'cleared');
+    return this.view();
+  }
+
+  /** The bytes to serve for a logo variant, or null when none is stored. */
+  logoBytes(variant: LogoVariant): Promise<Buffer | null> {
+    return this.storage.read(BrandingService.logoKey(variant));
+  }
+
+  /**
+   * The favicon bytes: the uploaded one, else the shipped default. The
+   * `<link rel="icon">` in index.html is static, so this route must always
+   * answer with an image — a 404 there would leave the browser's generic
+   * icon for good.
+   */
+  async faviconBytes(size: FaviconSize): Promise<{ bytes: Buffer; uploaded: boolean }> {
+    const stored = await this.storage.read(BrandingService.faviconKey(size));
+    if (stored) return { bytes: stored, uploaded: true };
+    const bytes = await readFile(join(__dirname, '../../assets', `default-favicon-${size}.png`));
+    return { bytes, uploaded: false };
+  }
+
+  /** The pond's own branding, defaulted — one place reads the settings blob. */
+  async pondBranding(pondId: string): Promise<PondBranding> {
+    const pond = await this.prisma.pond.findUnique({
+      where: { id: pondId },
+      select: { settings: true },
+    });
+    if (!pond) throw new NotFoundException();
+    return pondSettingsSchema.parse(pond.settings ?? {}).branding;
+  }
+
+  private async writePondBranding(
+    actor: User,
+    pondId: string,
+    next: PondBranding,
+    asset: 'logo' | 'logoDark' | 'favicon',
+    change: 'set' | 'cleared',
+  ): Promise<PondBranding> {
+    const pond = await this.prisma.pond.findUniqueOrThrow({
+      where: { id: pondId },
+      select: { settings: true },
+    });
+    const settings = pondSettingsSchema.parse(pond.settings ?? {});
+    await this.prisma.pond.update({
+      where: { id: pondId },
+      data: { settings: { ...settings, branding: next } as object },
+    });
+    await this.audit.record({
+      action: 'branding.changed',
+      actorId: actor.id,
+      targetType: 'pond',
+      targetId: pondId,
+      details: { scope: 'pond', pondId, asset, change },
+    });
+    return next;
+  }
+
+  /**
+   * A pond logo, charged to the pond's storage quota (issue #307).
+   *
+   * Without the charge, branding would be a way around the quota — and
+   * replacing a logo repeatedly would let a pond admin consume disk with no
+   * ceiling. Charged BEFORE the write, like attachments, so a race never
+   * leaves bytes on the volume without a reservation; the bytes a replaced
+   * asset frees are released first, so re-uploading the same logo is free
+   * rather than cumulative.
+   */
+  async setPondLogo(
+    actor: User,
+    pond: { id: string; ownerId: string },
+    variant: LogoVariant,
+    bytes: Buffer,
+  ): Promise<PondBranding> {
+    const size = this.assertUsablePng(bytes, MAX_LOGO_EDGE);
+    const current = await this.pondBranding(pond.id);
+    const previous = variant === 'dark' ? current.logoDark : current.logo;
+    await this.chargeQuota(pond, bytes.length, previous);
+    await this.storage.save(BrandingService.pondLogoKey(pond.id, variant), bytes);
+    const asset = this.assetOf(bytes, size);
+    return this.writePondBranding(
+      actor,
+      pond.id,
+      variant === 'dark' ? { ...current, logoDark: asset } : { ...current, logo: asset },
+      variant === 'dark' ? 'logoDark' : 'logo',
+      'set',
+    );
+  }
+
+  async clearPondLogo(
+    actor: User,
+    pond: { id: string; ownerId: string },
+    variant: LogoVariant,
+  ): Promise<PondBranding> {
+    const current = await this.pondBranding(pond.id);
+    const previous = variant === 'dark' ? current.logoDark : current.logo;
+    await this.storage.remove(BrandingService.pondLogoKey(pond.id, variant));
+    if (previous?.byteSize) await this.quotas.release(pond.id, previous.byteSize);
+    return this.writePondBranding(
+      actor,
+      pond.id,
+      variant === 'dark' ? { ...current, logoDark: null } : { ...current, logo: null },
+      variant === 'dark' ? 'logoDark' : 'logo',
+      'cleared',
+    );
+  }
+
+  async setPondFavicon(
+    actor: User,
+    pond: { id: string; ownerId: string },
+    files: Record<FaviconSize, Buffer>,
+  ): Promise<PondBranding> {
+    const checked = Object.entries(files).map(([declared, bytes]) => {
+      const size = this.assertUsablePng(bytes, 512);
+      const expected = Number(declared);
+      if (size.width !== expected || size.height !== expected) {
+        throw new BadRequestException({ code: 'branding_favicon_not_square' });
+      }
+      return { expected: expected as FaviconSize, bytes, size };
+    });
+    const current = await this.pondBranding(pond.id);
+    const total = checked.reduce((sum, entry) => sum + entry.bytes.length, 0);
+    await this.chargeQuota(pond, total, current.favicon);
+    for (const entry of checked) {
+      await this.storage.save(BrandingService.pondFaviconKey(pond.id, entry.expected), entry.bytes);
+    }
+    const small = checked.find((entry) => entry.expected === 32)!;
+    // The pair is charged together, so the stored size is the pair's — that
+    // is what a later release has to give back.
+    const asset = { ...this.assetOf(small.bytes, small.size), byteSize: total };
+    return this.writePondBranding(actor, pond.id, { ...current, favicon: asset }, 'favicon', 'set');
+  }
+
+  async clearPondFavicon(
+    actor: User,
+    pond: { id: string; ownerId: string },
+  ): Promise<PondBranding> {
+    const current = await this.pondBranding(pond.id);
+    for (const size of FAVICON_SIZES) {
+      await this.storage.remove(BrandingService.pondFaviconKey(pond.id, size));
+    }
+    if (current.favicon?.byteSize) await this.quotas.release(pond.id, current.favicon.byteSize);
+    return this.writePondBranding(
+      actor,
+      pond.id,
+      { ...current, favicon: null },
+      'favicon',
+      'cleared',
+    );
+  }
+
+  /** Bytes for a pond asset — null when the pond has none at that slot, which
+   *  is what makes the caller fall back to the instance level. */
+  pondLogoBytes(pondId: string, variant: LogoVariant): Promise<Buffer | null> {
+    return this.storage.read(BrandingService.pondLogoKey(pondId, variant));
+  }
+
+  pondFaviconBytes(pondId: string, size: FaviconSize): Promise<Buffer | null> {
+    return this.storage.read(BrandingService.pondFaviconKey(pondId, size));
+  }
+
+  /** Removes every branding file of a pond (issue #307's purge obligation). */
+  async removePondAssets(pondId: string): Promise<void> {
+    for (const key of BrandingService.pondKeys(pondId)) await this.storage.remove(key);
+  }
+
+  private record(
+    admin: User,
+    asset: 'logo' | 'logoDark' | 'favicon',
+    action: 'set' | 'cleared',
+  ): Promise<unknown> {
+    // `scope` is here from the start so the pond-level change (#307) is the
+    // same event with a different scope, not a second id in the catalogue.
+    return this.audit.record({
+      action: 'branding.changed',
+      actorId: admin.id,
+      targetType: 'setting',
+      targetId: `instance.${asset}`,
+      details: { scope: 'instance', asset, change: action },
+    });
+  }
+}

apps/api/src/branding/pond-branding.e2e.db.test.ts

@@ -0,0 +1,256 @@
+import { mkdtemp, rm } from 'node:fs/promises';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { deflateSync } from 'node:zlib';
+
+import { INestApplication } from '@nestjs/common';
+import { PrismaClient } from '@prisma/client';
+import request from 'supertest';
+import { afterAll, beforeAll, describe, expect, it } from 'vitest';
+
+import { AuthTokensService } from '../auth/auth-tokens.service';
+import { createTestApp, sessionCookieOf } from '../testing/test-app';
+import {
+  createTestPrisma,
+  deletePondsWhere,
+  grantOwnerAdmin,
+  hasTestDb,
+  uniqueSuffix,
+} from '../testing/test-db';
+import { TrashService } from '../trash/trash.service';
+import { UsersService } from '../users/users.service';
+
+import { BrandingService } from './branding.service';
+import { BrandingStorageService } from './branding-storage.service';
+
+const crcTable = Array.from({ length: 256 }, (_, n) => {
+  let c = n;
+  for (let k = 0; k < 8; k += 1) c = c & 1 ? 0xedb88320 ^ (c >>> 1) : c >>> 1;
+  return c >>> 0;
+});
+function crc32(buf: Buffer): number {
+  let c = 0xffffffff;
+  for (const byte of buf) c = crcTable[(c ^ byte) & 0xff]! ^ (c >>> 8);
+  return (c ^ 0xffffffff) >>> 0;
+}
+function chunk(type: string, data: Buffer): Buffer {
+  const length = Buffer.alloc(4);
+  length.writeUInt32BE(data.length);
+  const body = Buffer.concat([Buffer.from(type, 'ascii'), data]);
+  const crc = Buffer.alloc(4);
+  crc.writeUInt32BE(crc32(body));
+  return Buffer.concat([length, body, crc]);
+}
+/** A real PNG — the api reads the IHDR, so the header has to be genuine. */
+function png(size: number): Buffer {
+  const ihdr = Buffer.alloc(13);
+  ihdr.writeUInt32BE(size, 0);
+  ihdr.writeUInt32BE(size, 4);
+  ihdr[8] = 8;
+  ihdr[9] = 6;
+  return Buffer.concat([
+    Buffer.from([0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a]),
+    chunk('IHDR', ihdr),
+    chunk('IDAT', deflateSync(Buffer.alloc(size * (size * 4 + 1)))),
+    chunk('IEND', Buffer.alloc(0)),
+  ]);
+}
+
+describe.skipIf(!hasTestDb)('pond branding (e2e, issue #307)', () => {
+  let app: INestApplication;
+  let prisma: PrismaClient;
+  let storage: BrandingStorageService;
+  let brandingDir: string;
+  const suffix = uniqueSuffix();
+  const password = 'teichmarke mit eigenem logo 1';
+  const owner = { username: `pb-${suffix}` };
+  const member = { username: `pbm-${suffix}` };
+  let ownerCookie: string;
+  let memberCookie: string;
+  let pondId: string;
+
+  const api = () => request(app.getHttpServer());
+
+  beforeAll(async () => {
+    prisma = createTestPrisma();
+    await prisma.rateLimit.deleteMany({});
+    brandingDir = await mkdtemp(join(tmpdir(), 'dorfteich-pondbranding-'));
+    process.env.BRANDING_DIR = brandingDir;
+    app = await createTestApp();
+    storage = app.get(BrandingStorageService);
+    const users = app.get(UsersService);
+    const tokens = app.get(AuthTokensService);
+    // Verification through the endpoint, not `markEmailVerified`: only this
+    // path creates the personal pond these tests brand.
+    const verify = async (userId: string): Promise<void> => {
+      await api()
+        .post('/api/v1/auth/verify-email')
+        .send({ token: await tokens.issue(userId, 'EMAIL_VERIFICATION', 600) })
+        .expect(204);
+    };
+
+    const ownerUser = await users.createUser({
+      username: owner.username,
+      email: `${owner.username}@example.org`,
+      displayName: `Pond Branding Owner ${suffix}`,
+      password,
+      locale: 'en',
+    });
+    await verify(ownerUser.id);
+    const memberUser = await users.createUser({
+      username: member.username,
+      email: `${member.username}@example.org`,
+      displayName: `Pond Branding Member ${suffix}`,
+      password,
+      locale: 'en',
+    });
+    await verify(memberUser.id);
+
+    const login = async (username: string): Promise<string> =>
+      sessionCookieOf(
+        await api()
+          .post('/api/v1/auth/login')
+          .send({ usernameOrEmail: username, password })
+          .expect(200),
+      );
+    ownerCookie = await login(owner.username);
+    memberCookie = await login(member.username);
+
+    pondId = (
+      await prisma.pond.findFirstOrThrow({ where: { ownerId: ownerUser.id, type: 'PERSONAL' } })
+    ).id;
+    // A reader on the same pond: may see it, may not administer it. Through
+    // the API, not a raw row — the permission cache would not see the row
+    // (the documented rule for grants in tests).
+    await api()
+      .post(`/api/v1/ponds/${pondId}/grants`)
+      .set('Cookie', ownerCookie)
+      .send({
+        subjectType: 'user',
+        subjectId: memberUser.id,
+        role: 'reader',
+        scopeType: 'pond',
+        effect: 'allow',
+      })
+      .expect(201);
+  });
+
+  afterAll(async () => {
+    await prisma.roleGrant.deleteMany({
+      where: { pond: { owner: { username: { contains: suffix } } } },
+    });
+    await deletePondsWhere(prisma, { owner: { username: { contains: suffix } } });
+    await prisma.user.deleteMany({ where: { username: { contains: suffix } } });
+    await prisma.$disconnect();
+    await app.close();
+    await rm(brandingDir, { recursive: true, force: true });
+    delete process.env.BRANDING_DIR;
+  });
+
+  it('stores a pond logo, reports it, and serves it under the pond scope', async () => {
+    const view = await api()
+      .post(`/api/v1/ponds/${pondId}/branding/logo?variant=light`)
+      .set('Cookie', ownerCookie)
+      .attach('file', png(64), 'logo.png')
+      .expect(201);
+    expect(view.body.logo).toMatchObject({ width: 64, height: 64 });
+
+    const served = await api()
+      .get(`/api/v1/branding/logo?variant=light&pond=${pondId}`)
+      .expect(200);
+    expect(served.headers['content-type']).toContain('image/png');
+
+    // Without the pond scope the instance level answers — 404 here, since no
+    // instance logo is set. The two levels never leak into each other.
+    await api().get('/api/v1/branding/logo?variant=light').expect(404);
+  });
+
+  it('charges the pond quota and gives the bytes back when the logo is replaced', async () => {
+    const usageOf = async (): Promise<number> =>
+      Number(
+        (
+          await prisma.pondUsage.findUnique({
+            where: { pondId },
+            select: { storageBytesUsed: true },
+          })
+        )?.storageBytesUsed ?? 0,
+      );
+    const before = await usageOf();
+
+    const big = png(120);
+    await api()
+      .post(`/api/v1/ponds/${pondId}/branding/logo?variant=dark`)
+      .set('Cookie', ownerCookie)
+      .attach('file', big, 'logo.png')
+      .expect(201);
+    const afterUpload = await usageOf();
+    expect(afterUpload).toBe(before + big.length);
+
+    // Replacing releases the old reservation first — otherwise re-uploading
+    // the same logo would eat the quota again and again.
+    await api()
+      .post(`/api/v1/ponds/${pondId}/branding/logo?variant=dark`)
+      .set('Cookie', ownerCookie)
+      .attach('file', big, 'logo.png')
+      .expect(201);
+    expect(await usageOf()).toBe(afterUpload);
+
+    await api()
+      .delete(`/api/v1/ponds/${pondId}/branding/logo?variant=dark`)
+      .set('Cookie', ownerCookie)
+      .expect(200);
+    expect(await usageOf()).toBe(before);
+  });
+
+  it('refuses SVG at the pond level too — the rules do not relax for a pond admin', async () => {
+    const res = await api()
+      .post(`/api/v1/ponds/${pondId}/branding/logo?variant=light`)
+      .set('Cookie', ownerCookie)
+      .attach('file', Buffer.from('<svg xmlns="x"><script/></svg>'), 'x.png')
+      .expect(400);
+    expect(res.body.code).toBe('branding_svg_rejected');
+  });
+
+  it('lets a member read the pond branding but not change it', async () => {
+    await api().get(`/api/v1/ponds/${pondId}/branding`).set('Cookie', memberCookie).expect(200);
+    await api()
+      .post(`/api/v1/ponds/${pondId}/branding/logo?variant=light`)
+      .set('Cookie', memberCookie)
+      .attach('file', png(32), 'x.png')
+      .expect(403);
+    await api()
+      .delete(`/api/v1/ponds/${pondId}/branding/favicon`)
+      .set('Cookie', memberCookie)
+      .expect(403);
+  });
+
+  it('purging the pond removes its branding files', async () => {
+    // A pond of its own, so the purge does not take the shared fixture with it.
+    const ownerRow = await prisma.user.findFirstOrThrow({ where: { username: owner.username } });
+    const created = await prisma.pond.create({
+      data: {
+        name: `Purge Branding ${suffix}`,
+        slug: `purge-branding-${suffix}`,
+        type: 'SHARED',
+        ownerId: ownerRow.id,
+      },
+    });
+    // Raw grant row, before this pond's first permission query — the
+    // documented exception to "grants through the API".
+    await grantOwnerAdmin(prisma, created.id, ownerRow.id);
+    await api()
+      .post(`/api/v1/ponds/${created.id}/branding/logo?variant=light`)
+      .set('Cookie', ownerCookie)
+      .attach('file', png(48), 'logo.png')
+      .expect(201);
+    expect(await storage.read(BrandingService.pondLogoKey(created.id, 'light'))).not.toBeNull();
+
+    await prisma.pond.update({ where: { id: created.id }, data: { deletedAt: new Date() } });
+    const trash = app.get(TrashService);
+    await trash.purgePondNow(ownerRow, created.id);
+
+    // The purge standard is absolute: after it nothing referencing the pond
+    // survives — rows OR files.
+    expect(await storage.read(BrandingService.pondLogoKey(created.id, 'light'))).toBeNull();
+  });
+});

apps/api/src/files/attachment-integrity.e2e.db.test.ts

@@ -7,7 +7,7 @@ import { afterAll, beforeAll, describe, expect, it } from 'vitest';
 
 import { AuthTokensService } from '../auth/auth-tokens.service';
 import { createTestApp } from '../testing/test-app';
-import { createTestPrisma, hasTestDb, uniqueSuffix } from '../testing/test-db';
+import { createTestPrisma, deletePondsWhere, hasTestDb, uniqueSuffix } from '../testing/test-db';
 import { UsersService } from '../users/users.service';
 
 import { FileStorageService } from './file-storage.service';
@@ -74,7 +74,7 @@ describe.skipIf(!hasTestDb)('attachment integrity (e2e, issue #199)', () => {
     await prisma.attachment.deleteMany({ where: { pondId } });
     const where = { pond: { owner: { username: { contains: suffix } } } };
     await prisma.roleGrant.deleteMany({ where });
-    await prisma.pond.deleteMany({ where: { owner: { username: { contains: suffix } } } });
+    await deletePondsWhere(prisma, { owner: { username: { contains: suffix } } });
     await prisma.user.deleteMany({ where: { username: { contains: suffix } } });
     await prisma.$disconnect();
     await app.close();

apps/api/src/fonts/custom-font-storage.service.ts

@@ -0,0 +1,55 @@
+import { mkdir, readFile, rm, writeFile } from 'node:fs/promises';
+import { join } from 'node:path';
+
+import { Injectable } from '@nestjs/common';
+import type { FontUploadFormat } from '@dorfteich/shared';
+
+import { AppConfig } from '../config/app-config.service';
+
+/**
+ * Filesystem binding for operator-uploaded fonts (issue #303, ADR 0016 §#303).
+ *
+ * The layout mirrors the baked-in catalog — `<slug>/<slug>-<weight>.woff2` —
+ * so the PDF exporter's `@font-face` builder needs no special case beyond
+ * choosing the directory.
+ *
+ * That directory is `CUSTOM_FONTS_DIR`, NOT `FONTS_DIR`: the latter is baked
+ * into the image, so anything written there disappears on the next deploy and
+ * never reaches a backup. This one is a sibling of the uploads and plugins
+ * mounts and travels in the restore set (`apps/backup/src/data-dirs.ts`).
+ */
+@Injectable()
+export class CustomFontStorageService {
+  constructor(private readonly config: AppConfig) {}
+
+  private dirFor(slug: string): string {
+    return join(this.config.env.CUSTOM_FONTS_DIR, slug);
+  }
+
+  fileNameFor(slug: string, weight: number, format: FontUploadFormat): string {
+    return `${slug}-${weight}.${format}`;
+  }
+
+  pathFor(slug: string, weight: number, format: FontUploadFormat): string {
+    return join(this.dirFor(slug), this.fileNameFor(slug, weight, format));
+  }
+
+  async save(slug: string, weight: number, format: FontUploadFormat, bytes: Buffer): Promise<void> {
+    await mkdir(this.dirFor(slug), { recursive: true });
+    await writeFile(this.pathFor(slug, weight, format), bytes);
+  }
+
+  read(slug: string, weight: number, format: FontUploadFormat): Promise<Buffer> {
+    return readFile(this.pathFor(slug, weight, format));
+  }
+
+  /** Removes the family's whole directory. Missing is fine — deletion must
+   * stay idempotent so a half-failed upload can still be cleaned up. */
+  async deleteFamily(slug: string): Promise<void> {
+    await rm(this.dirFor(slug), { recursive: true, force: true });
+  }
+
+  async deleteWeight(slug: string, weight: number, format: FontUploadFormat): Promise<void> {
+    await rm(this.pathFor(slug, weight, format), { force: true });
+  }
+}

apps/api/src/fonts/custom-fonts.controller.ts

@@ -0,0 +1,164 @@
+import {
+  BadRequestException,
+  Controller,
+  Delete,
+  Get,
+  HttpCode,
+  Param,
+  Post,
+  Req,
+  Res,
+  UploadedFiles,
+  UseGuards,
+  UseInterceptors,
+} from '@nestjs/common';
+import { AnyFilesInterceptor } from '@nestjs/platform-express';
+import {
+  CustomFontView,
+  FONT_WEIGHTS,
+  MAX_FONT_FILE_BYTES,
+  createCustomFontInputSchema,
+} from '@dorfteich/shared';
+import type { Response } from 'express';
+
+import { SiteAdminGuard } from '../admin/site-admin.guard';
+import { AuthedRequest, Public } from '../auth/auth.guard';
+import { AuthenticatedOnly } from '../permissions/permission.decorators';
+import { CustomFontStorageService } from './custom-font-storage.service';
+import { CustomFontsService, WeightUpload } from './custom-fonts.service';
+
+/** Multipart field names: `woff2-<weight>` and the optional `woff-<weight>`. */
+const FILE_FIELD = /^(woff2|woff)-(\d{3})$/;
+
+function parseUploads(files: Express.Multer.File[] | undefined): WeightUpload[] {
+  const byWeight = new Map<number, WeightUpload>();
+  for (const file of files ?? []) {
+    const match = FILE_FIELD.exec(file.fieldname);
+    if (!match) throw new BadRequestException({ code: 'font_unexpected_field' });
+    const weight = Number(match[2]);
+    if (!(FONT_WEIGHTS as readonly number[]).includes(weight)) {
+      throw new BadRequestException({ code: 'font_weight_invalid' });
+    }
+    const entry = byWeight.get(weight) ?? { weight, woff2: Buffer.alloc(0) };
+    if (match[1] === 'woff2') entry.woff2 = file.buffer;
+    else entry.woff = file.buffer;
+    byWeight.set(weight, entry);
+  }
+  // A WOFF without its WOFF2 would produce a weight the PDF path cannot
+  // embed — the exporter reads WOFF2 only.
+  for (const entry of byWeight.values()) {
+    if (entry.woff2.length === 0) throw new BadRequestException({ code: 'font_woff2_missing' });
+  }
+  return [...byWeight.values()].sort((a, b) => a.weight - b.weight);
+}
+
+/** Site-Admin management of operator-uploaded fonts (issue #303). */
+@Controller('admin/fonts')
+@UseGuards(SiteAdminGuard)
+export class CustomFontsAdminController {
+  constructor(private readonly fonts: CustomFontsService) {}
+
+  @Get()
+  list(): Promise<CustomFontView[]> {
+    return this.fonts.list();
+  }
+
+  @Post()
+  @UseInterceptors(AnyFilesInterceptor({ limits: { fileSize: MAX_FONT_FILE_BYTES } }))
+  async create(
+    @Req() request: AuthedRequest,
+    @UploadedFiles() files: Express.Multer.File[] | undefined,
+  ): Promise<CustomFontView> {
+    // The metadata rides as ordinary multipart fields next to the files.
+    const input = createCustomFontInputSchema.parse({
+      family: request.body?.family,
+      category: request.body?.category,
+      licence: request.body?.licence,
+      licenceUrl: request.body?.licenceUrl || null,
+    });
+    return this.fonts.create(request.user!, input, parseUploads(files));
+  }
+
+  @Post(':id/weights')
+  @UseInterceptors(AnyFilesInterceptor({ limits: { fileSize: MAX_FONT_FILE_BYTES } }))
+  async addWeight(
+    @Param('id') id: string,
+    @Req() request: AuthedRequest,
+    @UploadedFiles() files: Express.Multer.File[] | undefined,
+  ): Promise<CustomFontView> {
+    const uploads = parseUploads(files);
+    if (uploads.length !== 1) throw new BadRequestException({ code: 'font_one_weight_expected' });
+    return this.fonts.addWeight(request.user!, id, uploads[0]!);
+  }
+
+  /** How many live ponds still use the family — shown before deleting. */
+  @Get(':id/usage')
+  async usage(@Param('id') id: string): Promise<{ pondsAffected: number }> {
+    const font = (await this.fonts.list()).find((entry) => entry.id === id);
+    if (!font) throw new BadRequestException({ code: 'not_found' });
+    return { pondsAffected: await this.fonts.pondsUsing(font.family) };
+  }
+
+  @Delete(':id')
+  @HttpCode(204)
+  async remove(@Param('id') id: string, @Req() request: AuthedRequest): Promise<void> {
+    await this.fonts.remove(request.user!, id);
+  }
+}
+
+/**
+ * Reading side of the uploaded fonts: the family list every signed-in user
+ * needs, and the bytes themselves.
+ *
+ * The listing is NOT site-admin-gated (issue #304): every signed-in user picks
+ * fonts in their pond's Appearance settings, reads the licence page, and needs
+ * the `@font-face` rules injected — the admin list at `/admin/fonts` carries
+ * the same data, so gating this one would only force a second, admin-only UI.
+ *
+ * The file route is unauthenticated on purpose: a font is referenced from CSS,
+ * and the login screen carries the pond-independent chrome — an authenticated
+ * font URL would simply not load. The bytes are branding, not content.
+ */
+@Controller('fonts/custom')
+export class CustomFontsFileController {
+  constructor(
+    private readonly storage: CustomFontStorageService,
+    private readonly fonts: CustomFontsService,
+  ) {}
+
+  // Explicit access declaration, as every route needs (issue #52's fence
+  // `route-permissions.e2e.db.test.ts`): a session, no further permission —
+  // the list says which families exist, which is what the pickers offer.
+  @AuthenticatedOnly()
+  @Get()
+  list(): Promise<CustomFontView[]> {
+    return this.fonts.list();
+  }
+
+  @Public()
+  @Get(':slug/:file')
+  async serve(
+    @Param('slug') slug: string,
+    @Param('file') file: string,
+    @Res() res: Response,
+  ): Promise<void> {
+    const match = /^([a-z0-9-]+)-(\d{3})\.(woff2|woff)$/.exec(file);
+    // The slug must match the file's own prefix, so the path cannot be used
+    // to reach a different family's directory.
+    if (!match || match[1] !== slug) throw new BadRequestException({ code: 'not_found' });
+
+    const known = (await this.fonts.list()).find((entry) => entry.slug === slug);
+    if (!known) throw new BadRequestException({ code: 'not_found' });
+
+    const format = match[3] as 'woff2' | 'woff';
+    const bytes = await this.storage
+      .read(slug, Number(match[2]), format)
+      .catch(() => Promise.reject(new BadRequestException({ code: 'not_found' })));
+
+    res.setHeader('Content-Type', format === 'woff2' ? 'font/woff2' : 'font/woff');
+    // Slug + weight + format identify the bytes; a changed family is a new
+    // upload under a new id, so a long lifetime is safe.
+    res.setHeader('Cache-Control', 'public, max-age=31536000, immutable');
+    res.send(bytes);
+  }
+}

apps/api/src/fonts/custom-fonts.e2e.db.test.ts

@@ -0,0 +1,244 @@
+import { mkdtemp, readFile, rm } from 'node:fs/promises';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+
+import { INestApplication } from '@nestjs/common';
+import { PrismaClient } from '@prisma/client';
+import request from 'supertest';
+import { afterAll, beforeAll, describe, expect, it } from 'vitest';
+
+import { createTestApp, sessionCookieOf } from '../testing/test-app';
+import { createTestPrisma, deletePondsWhere, hasTestDb, uniqueSuffix } from '../testing/test-db';
+import { UsersService } from '../users/users.service';
+
+/** Smallest bytes that pass the magic check — the api never parses further. */
+const woff2 = (): Buffer => Buffer.concat([Buffer.from('wOF2'), Buffer.alloc(64)]);
+const woff = (): Buffer => Buffer.concat([Buffer.from('wOFF'), Buffer.alloc(64)]);
+
+describe.skipIf(!hasTestDb)('custom fonts (e2e, issue #303)', () => {
+  let app: INestApplication;
+  let prisma: PrismaClient;
+  let fontsDir: string;
+  const suffix = uniqueSuffix();
+  const password = 'schriftverwaltung mit stil 1';
+  const admin = { username: `fa-${suffix}`, displayName: `Font Admin ${suffix}` };
+  const plain = { username: `fp-${suffix}`, displayName: `Font Plain ${suffix}` };
+  let adminCookie: string;
+  let plainCookie: string;
+
+  const api = () => request(app.getHttpServer());
+
+  beforeAll(async () => {
+    prisma = createTestPrisma();
+    await prisma.rateLimit.deleteMany({});
+    // A real directory so the storage layer is exercised, not mocked — the
+    // point of this suite is that bytes actually land somewhere retrievable.
+    fontsDir = await mkdtemp(join(tmpdir(), 'dorfteich-fonts-'));
+    process.env.CUSTOM_FONTS_DIR = fontsDir;
+    app = await createTestApp();
+    const users = app.get(UsersService);
+
+    const adminUser = await users.createUser({
+      username: admin.username,
+      email: `${admin.username}@example.org`,
+      displayName: admin.displayName,
+      password,
+      locale: 'en',
+    });
+    await users.markEmailVerified(adminUser.id);
+    await prisma.user.update({ where: { id: adminUser.id }, data: { isSiteAdmin: true } });
+    // additional_ponds defaults to 0 (ADR 0011) and the instance default is
+    // never raised — the usage test needs a pond, so grant an override.
+    await prisma.quotaOverride.create({
+      data: {
+        subjectType: 'USER',
+        subjectId: adminUser.id,
+        quotaKey: 'additional_ponds',
+        value: 10,
+      },
+    });
+
+    const plainUser = await users.createUser({
+      username: plain.username,
+      email: `${plain.username}@example.org`,
+      displayName: plain.displayName,
+      password,
+      locale: 'en',
+    });
+    await users.markEmailVerified(plainUser.id);
+
+    const login = async (username: string): Promise<string> =>
+      sessionCookieOf(
+        await api()
+          .post('/api/v1/auth/login')
+          .send({ usernameOrEmail: username, password })
+          .expect(200),
+      );
+    adminCookie = await login(admin.username);
+    plainCookie = await login(plain.username);
+  });
+
+  afterAll(async () => {
+    await prisma.customFont.deleteMany({});
+    const ids = (
+      await prisma.user.findMany({
+        where: { username: { contains: suffix } },
+        select: { id: true },
+      })
+    ).map((row) => row.id);
+    await prisma.quotaOverride.deleteMany({ where: { subjectId: { in: ids } } });
+    await deletePondsWhere(prisma, { owner: { username: { contains: suffix } } });
+    await prisma.user.deleteMany({ where: { username: { contains: suffix } } });
+    await prisma.$disconnect();
+    await app.close();
+    await rm(fontsDir, { recursive: true, force: true });
+    delete process.env.CUSTOM_FONTS_DIR;
+  });
+
+  it('uploads a family, writes the bytes, and serves them back', async () => {
+    const created = await api()
+      .post('/api/v1/admin/fonts')
+      .set('Cookie', adminCookie)
+      .field('family', `Hausschrift ${suffix}`)
+      .field('category', 'serif')
+      .field('licence', 'Commercial — Foundry XY')
+      .attach('woff2-400', woff2(), 'x.woff2')
+      .attach('woff-400', woff(), 'x.woff')
+      .expect(201);
+
+    expect(created.body.weights).toEqual([400]);
+    expect(created.body.licence).toBe('Commercial — Foundry XY');
+
+    const slug = created.body.slug as string;
+    // The bytes are really on disk, in the catalog's layout.
+    const onDisk = await readFile(join(fontsDir, slug, `${slug}-400.woff2`));
+    expect(onDisk.subarray(0, 4).toString()).toBe('wOF2');
+
+    // …and reachable without a session: a font is fetched from CSS.
+    const served = await api().get(`/api/v1/fonts/custom/${slug}/${slug}-400.woff2`).expect(200);
+    expect(served.headers['content-type']).toContain('font/woff2');
+  });
+
+  it('rejects a file that is not a font, whatever it is called', async () => {
+    const res = await api()
+      .post('/api/v1/admin/fonts')
+      .set('Cookie', adminCookie)
+      .field('family', `Fake ${suffix}`)
+      .field('category', 'sans-serif')
+      .field('licence', 'X')
+      .attach('woff2-400', Buffer.from('\x89PNG\r\n\x1a\n and more'), 'evil.woff2')
+      .expect(400);
+    expect(res.body.code).toBe('font_file_not_a_font');
+  });
+
+  it('refuses a family name that a catalog font already owns', async () => {
+    const res = await api()
+      .post('/api/v1/admin/fonts')
+      .set('Cookie', adminCookie)
+      .field('family', 'Roboto')
+      .field('category', 'sans-serif')
+      .field('licence', 'X')
+      .attach('woff2-400', woff2(), 'x.woff2')
+      .expect(409);
+    expect(res.body.code).toBe('font_family_reserved');
+  });
+
+  it('refuses a weight whose WOFF2 is missing', async () => {
+    const res = await api()
+      .post('/api/v1/admin/fonts')
+      .set('Cookie', adminCookie)
+      .field('family', `NurWoff ${suffix}`)
+      .field('category', 'sans-serif')
+      .field('licence', 'X')
+      .attach('woff-400', woff(), 'x.woff')
+      .expect(400);
+    expect(res.body.code).toBe('font_woff2_missing');
+  });
+
+  /**
+   * Issue #304: an ordinary member picks fonts in their pond's Appearance
+   * settings and reads the licence page, so the family list cannot be
+   * Site-Admin-only — only the management routes are.
+   */
+  it('lets any signed-in user read the family list, but nobody anonymous', async () => {
+    await api()
+      .post('/api/v1/admin/fonts')
+      .set('Cookie', adminCookie)
+      .field('family', `Leseschrift ${suffix}`)
+      .field('category', 'monospace')
+      .field('licence', 'Read me')
+      .attach('woff2-500', woff2(), 'x.woff2')
+      .expect(201);
+
+    const listed = await api().get('/api/v1/fonts/custom').set('Cookie', plainCookie).expect(200);
+    const seen = (listed.body as { family: string; weights: number[] }[]).find(
+      (font) => font.family === `Leseschrift ${suffix}`,
+    );
+    expect(seen?.weights).toEqual([500]);
+
+    await api().get('/api/v1/fonts/custom').expect(401);
+  });
+
+  it('keeps every management route away from a non-admin', async () => {
+    await api().get('/api/v1/admin/fonts').set('Cookie', plainCookie).expect(403);
+    await api()
+      .post('/api/v1/admin/fonts')
+      .set('Cookie', plainCookie)
+      .field('family', `Nope ${suffix}`)
+      .field('category', 'serif')
+      .field('licence', 'X')
+      .attach('woff2-400', woff2(), 'x.woff2')
+      .expect(403);
+  });
+
+  it('counts the ponds a family is used by, and deletion leaves them working', async () => {
+    const created = await api()
+      .post('/api/v1/admin/fonts')
+      .set('Cookie', adminCookie)
+      .field('family', `Zählschrift ${suffix}`)
+      .field('category', 'sans-serif')
+      .field('licence', 'X')
+      .attach('woff2-400', woff2(), 'x.woff2')
+      .expect(201);
+
+    const pond = await api()
+      .post('/api/v1/ponds')
+      .set('Cookie', adminCookie)
+      .send({ name: `Schriftteich ${suffix}` })
+      .expect(201);
+    await api()
+      .patch(`/api/v1/ponds/${pond.body.id}`)
+      .set('Cookie', adminCookie)
+      .send({ fonts: { body: { family: `Zählschrift ${suffix}`, weight: 400 } } })
+      .expect(200);
+
+    const usage = await api()
+      .get(`/api/v1/admin/fonts/${created.body.id}/usage`)
+      .set('Cookie', adminCookie)
+      .expect(200);
+    expect(usage.body.pondsAffected).toBe(1);
+
+    // Deletion is never blocked by usage.
+    await api()
+      .delete(`/api/v1/admin/fonts/${created.body.id}`)
+      .set('Cookie', adminCookie)
+      .expect(204);
+
+    // The pond still resolves — it keeps the stored family name and falls
+    // back to the system stack, rather than breaking.
+    const after = await api()
+      .get(`/api/v1/ponds/${pond.body.slug}`)
+      .set('Cookie', adminCookie)
+      .expect(200);
+    expect(after.body.settings.fonts.body.family).toBe(`Zählschrift ${suffix}`);
+    expect(
+      await api().get('/api/v1/admin/fonts').set('Cookie', adminCookie).expect(200),
+    ).toBeTruthy();
+
+    const audit = await prisma.auditEntry.findFirst({
+      where: { action: 'font.deleted', targetId: created.body.id },
+    });
+    expect(audit).not.toBeNull();
+    expect(audit!.details).toMatchObject({ pondsAffected: 1 });
+  });
+});

apps/api/src/fonts/custom-fonts.service.ts

@@ -0,0 +1,249 @@
+import {
+  BadRequestException,
+  ConflictException,
+  Injectable,
+  NotFoundException,
+} from '@nestjs/common';
+import {
+  CreateCustomFontInput,
+  CustomFontView,
+  FONT_CATALOG,
+  FontCategory,
+  FontUploadFormat,
+  MAX_FONT_FILE_BYTES,
+  MAX_FONT_WEIGHTS,
+  fontSlug,
+  hasFontMagic,
+} from '@dorfteich/shared';
+import { User } from '@prisma/client';
+import { PinoLogger } from 'nestjs-pino';
+
+import { AuditService } from '../audit/audit.service';
+import { PrismaService } from '../prisma/prisma.service';
+import { CustomFontStorageService } from './custom-font-storage.service';
+
+/** One weight's bytes as they arrive from the controller. */
+export interface WeightUpload {
+  weight: number;
+  woff2: Buffer;
+  woff?: Buffer;
+}
+
+/**
+ * Operator-uploaded font families (issue #303, ADR 0016 §#303).
+ *
+ * Site-Admin-only, additive to the compile-time catalog, and deliberately
+ * incurious about the files: the api validates the magic number and the size
+ * and then stores the bytes. Family, category and licence come from the form.
+ */
+@Injectable()
+export class CustomFontsService {
+  constructor(
+    private readonly prisma: PrismaService,
+    private readonly storage: CustomFontStorageService,
+    private readonly audit: AuditService,
+    private readonly logger: PinoLogger,
+  ) {
+    this.logger.setContext(CustomFontsService.name);
+  }
+
+  /**
+   * Rejects bytes that are not what they claim to be, before anything is
+   * written. Deliberately the ONLY inspection: parsing the font would gain
+   * metadata the form already carries, at the price of a known
+   * memory-safety surface (ADR 0016 §#303).
+   */
+  private assertUsableFont(bytes: Buffer, format: FontUploadFormat): void {
+    if (bytes.length === 0) throw new BadRequestException({ code: 'font_file_empty' });
+    if (bytes.length > MAX_FONT_FILE_BYTES) {
+      throw new BadRequestException({ code: 'font_file_too_large' });
+    }
+    if (!hasFontMagic(bytes, format)) {
+      throw new BadRequestException({ code: 'font_file_not_a_font' });
+    }
+  }
+
+  /**
+   * A custom family must not collide with a catalog one, by name or by slug:
+   * a pond stores `fonts.<slot>.family` as a plain string, so two families
+   * answering to the same name would make the PDF path embed whichever file
+   * it happened to find.
+   */
+  private async assertNameIsFree(family: string, slug: string): Promise<void> {
+    const catalogHit = FONT_CATALOG.some(
+      (entry) => entry.family === family || fontSlug(entry.family) === slug,
+    );
+    if (catalogHit) throw new ConflictException({ code: 'font_family_reserved' });
+    const existing = await this.prisma.customFont.findFirst({
+      where: { OR: [{ family }, { slug }] },
+      select: { id: true },
+    });
+    if (existing) throw new ConflictException({ code: 'font_family_exists' });
+  }
+
+  private viewOf(font: {
+    id: string;
+    family: string;
+    slug: string;
+    category: string;
+    licence: string;
+    licenceUrl: string | null;
+    createdAt: Date;
+    weights: { weight: number }[];
+  }): CustomFontView {
+    return {
+      id: font.id,
+      family: font.family,
+      slug: font.slug,
+      category: font.category as FontCategory,
+      licence: font.licence,
+      licenceUrl: font.licenceUrl,
+      weights: font.weights.map((row) => row.weight).sort((a, b) => a - b),
+      createdAt: font.createdAt.toISOString(),
+    };
+  }
+
+  async list(): Promise<CustomFontView[]> {
+    const fonts = await this.prisma.customFont.findMany({
+      orderBy: { family: 'asc' },
+      include: { weights: { select: { weight: true } } },
+    });
+    return fonts.map((font) => this.viewOf(font));
+  }
+
+  async create(
+    admin: User,
+    input: CreateCustomFontInput,
+    uploads: WeightUpload[],
+  ): Promise<CustomFontView> {
+    if (uploads.length === 0) throw new BadRequestException({ code: 'font_no_weights' });
+    if (uploads.length > MAX_FONT_WEIGHTS) {
+      throw new BadRequestException({ code: 'font_too_many_weights' });
+    }
+    for (const upload of uploads) {
+      this.assertUsableFont(upload.woff2, 'woff2');
+      if (upload.woff) this.assertUsableFont(upload.woff, 'woff');
+    }
+
+    const slug = fontSlug(input.family);
+    if (!slug) throw new BadRequestException({ code: 'font_family_unusable' });
+    await this.assertNameIsFree(input.family, slug);
+
+    // Row first, then bytes: a row without files is repairable (re-upload the
+    // weight), while files without a row would be invisible litter.
+    const font = await this.prisma.customFont.create({
+      data: {
+        family: input.family,
+        slug,
+        category: input.category,
+        licence: input.licence,
+        licenceUrl: input.licenceUrl,
+        uploadedBy: admin.id,
+        weights: {
+          create: uploads.map((upload) => ({
+            weight: upload.weight,
+            hasWoff: Boolean(upload.woff),
+            byteSize: upload.woff2.length,
+          })),
+        },
+      },
+      include: { weights: { select: { weight: true } } },
+    });
+
+    for (const upload of uploads) {
+      await this.storage.save(slug, upload.weight, 'woff2', upload.woff2);
+      if (upload.woff) await this.storage.save(slug, upload.weight, 'woff', upload.woff);
+    }
+
+    await this.audit.record({
+      action: 'font.uploaded',
+      actorId: admin.id,
+      targetType: 'font',
+      targetId: font.id,
+      details: { family: font.family },
+    });
+    return this.viewOf(font);
+  }
+
+  async addWeight(admin: User, fontId: string, upload: WeightUpload): Promise<CustomFontView> {
+    this.assertUsableFont(upload.woff2, 'woff2');
+    if (upload.woff) this.assertUsableFont(upload.woff, 'woff');
+
+    const font = await this.prisma.customFont.findUnique({
+      where: { id: fontId },
+      include: { weights: { select: { weight: true } } },
+    });
+    if (!font) throw new NotFoundException();
+    if (font.weights.length >= MAX_FONT_WEIGHTS) {
+      throw new BadRequestException({ code: 'font_too_many_weights' });
+    }
+    if (font.weights.some((row) => row.weight === upload.weight)) {
+      throw new ConflictException({ code: 'font_weight_exists' });
+    }
+
+    await this.prisma.customFontWeight.create({
+      data: {
+        fontId,
+        weight: upload.weight,
+        hasWoff: Boolean(upload.woff),
+        byteSize: upload.woff2.length,
+      },
+    });
+    await this.storage.save(font.slug, upload.weight, 'woff2', upload.woff2);
+    if (upload.woff) await this.storage.save(font.slug, upload.weight, 'woff', upload.woff);
+
+    await this.audit.record({
+      action: 'font.uploaded',
+      actorId: admin.id,
+      targetType: 'font',
+      targetId: fontId,
+      details: { family: font.family, weight: upload.weight },
+    });
+    const updated = await this.prisma.customFont.findUniqueOrThrow({
+      where: { id: fontId },
+      include: { weights: { select: { weight: true } } },
+    });
+    return this.viewOf(updated);
+  }
+
+  /**
+   * How many live ponds still name this family in any of their three font
+   * slots. Shown before deletion — those ponds keep working (an unknown
+   * family falls back to the system stack) but they visibly change.
+   */
+  async pondsUsing(family: string): Promise<number> {
+    const rows = await this.prisma.$queryRaw<{ count: bigint }[]>`
+      SELECT count(*)::bigint AS count
+        FROM ponds
+       WHERE deleted_at IS NULL
+         AND (settings #>> '{fonts,heading,family}' = ${family}
+           OR settings #>> '{fonts,body,family}' = ${family}
+           OR settings #>> '{fonts,mono,family}' = ${family})
+    `;
+    return Number(rows[0]?.count ?? 0);
+  }
+
+  /**
+   * Deletion is never blocked by usage. `fontStack` already yields the system
+   * fallback for an unknown family, so affected ponds degrade rather than
+   * break, and re-uploading the family restores them — but the count travels
+   * into the audit entry so the change is not silent.
+   */
+  async remove(admin: User, fontId: string): Promise<void> {
+    const font = await this.prisma.customFont.findUnique({ where: { id: fontId } });
+    if (!font) throw new NotFoundException();
+    const pondsAffected = await this.pondsUsing(font.family);
+
+    await this.prisma.customFont.delete({ where: { id: fontId } });
+    await this.storage.deleteFamily(font.slug);
+
+    await this.audit.record({
+      action: 'font.deleted',
+      actorId: admin.id,
+      targetType: 'font',
+      targetId: fontId,
+      details: { family: font.family, pondsAffected },
+    });
+    this.logger.info({ fontId, family: font.family, pondsAffected }, 'custom font deleted');
+  }
+}

apps/api/src/fonts/fonts.module.ts

@@ -0,0 +1,14 @@
+import { Module } from '@nestjs/common';
+
+import { CustomFontStorageService } from './custom-font-storage.service';
+import { CustomFontsAdminController, CustomFontsFileController } from './custom-fonts.controller';
+import { CustomFontsService } from './custom-fonts.service';
+
+/** Operator-uploaded fonts (issue #303, ADR 0016 §#303). Exports the service
+ * so the PDF exporter can resolve a pond's font to a custom family. */
+@Module({
+  controllers: [CustomFontsAdminController, CustomFontsFileController],
+  providers: [CustomFontsService, CustomFontStorageService],
+  exports: [CustomFontsService, CustomFontStorageService],
+})
+export class FontsModule {}

apps/api/src/i18n/api-i18n.ts

@@ -1,10 +1,12 @@
 import deErrors from '@dorfteich/shared/i18n/de/errors.json';
 import deLegal from '@dorfteich/shared/i18n/de/legal.json';
 import deMails from '@dorfteich/shared/i18n/de/mails.json';
+import dePonds from '@dorfteich/shared/i18n/de/ponds.json';
 import deTasks from '@dorfteich/shared/i18n/de/tasks.json';
 import enErrors from '@dorfteich/shared/i18n/en/errors.json';
 import enLegal from '@dorfteich/shared/i18n/en/legal.json';
 import enMails from '@dorfteich/shared/i18n/en/mails.json';
+import enPonds from '@dorfteich/shared/i18n/en/ponds.json';
 import enTasks from '@dorfteich/shared/i18n/en/tasks.json';
 import { createInstance, type i18n as I18n } from 'i18next';
 
@@ -17,8 +19,8 @@ export const apiI18n: I18n = createInstance();
 
 void apiI18n.init({
   resources: {
-    en: { errors: enErrors, mails: enMails, legal: enLegal, tasks: enTasks },
-    de: { errors: deErrors, mails: deMails, legal: deLegal, tasks: deTasks },
+    en: { errors: enErrors, mails: enMails, legal: enLegal, tasks: enTasks, ponds: enPonds },
+    de: { errors: deErrors, mails: deMails, legal: deLegal, tasks: deTasks, ponds: dePonds },
   },
   fallbackLng: 'en',
   supportedLngs: ['de', 'en'],

apps/api/src/import-export/conversion-job.e2e.db.test.ts

@@ -5,7 +5,7 @@ import { afterAll, beforeAll, describe, expect, it } from 'vitest';
 
 import { AuthTokensService } from '../auth/auth-tokens.service';
 import { createTestApp, sessionCookieOf } from '../testing/test-app';
-import { createTestPrisma, hasTestDb, uniqueSuffix } from '../testing/test-db';
+import { createTestPrisma, deletePondsWhere, hasTestDb, uniqueSuffix } from '../testing/test-db';
 import { UsersService } from '../users/users.service';
 
 import { ConversionJobService } from './conversion-job.service';
@@ -108,7 +108,7 @@ describe.skipIf(!hasTestDb)('conversion job queue (e2e, issue #62)', () => {
     // grant); clear those before the users they reference.
     const where = { pond: { owner: { username: { contains: suffix } } } };
     await prisma.roleGrant.deleteMany({ where });
-    await prisma.pond.deleteMany({ where: { owner: { username: { contains: suffix } } } });
+    await deletePondsWhere(prisma, { owner: { username: { contains: suffix } } });
     await prisma.user.deleteMany({ where: { username: { contains: suffix } } });
     await prisma.$disconnect();
     await app.close();

apps/api/src/import-export/export.controller.ts

@@ -1,5 +1,10 @@
-import { Body, Controller, Get, Param, Post, Req, Res } from '@nestjs/common';
-import { ConversionJobView, PageExportInput, pageExportInputSchema } from '@dorfteich/shared';
+import { Body, Controller, Get, Param, Post, Req, Res, UseGuards } from '@nestjs/common';
+import {
+  ConversionJobView,
+  PageExportInput,
+  PondArchivePreview,
+  pageExportInputSchema,
+} from '@dorfteich/shared';
 import type { Response } from 'express';
 
 import { AuthedRequest } from '../auth/auth.guard';
@@ -7,7 +12,10 @@ import { ZodValidationPipe } from '../common/zod-validation.pipe';
 import { RequiresPagePermission, RequiresPondRole } from '../permissions/permission.decorators';
 import { readActorOf } from '../read-trail/read-actor';
 
+import { SiteAdminGuard } from '../admin/site-admin.guard';
+
 import { ExportService } from './export.service';
+import { PondArchiveService } from './pond-archive.service';
 
 /**
  * Export endpoints (ADR 0009, issue #65): a whole pond as a ZIP of Markdown and
@@ -16,7 +24,41 @@ import { ExportService } from './export.service';
  */
 @Controller()
 export class ExportController {
-  constructor(private readonly exports: ExportService) {}
+  constructor(
+    private readonly exports: ExportService,
+    private readonly archives: PondArchiveService,
+  ) {}
+
+  /**
+   * How much of the pond this requester's archive would contain (issue #305).
+   * Asked before the download so the UI can name the number of omitted pages:
+   * an archive silently missing content is worse than no archive, because it
+   * ends the search.
+   */
+  @Get('ponds/:pondId/archive/preview')
+  @RequiresPondRole('pond_admin', { idParam: 'pondId' })
+  archivePreview(
+    @Param('pondId') pondId: string,
+    @Req() request: AuthedRequest,
+  ): Promise<PondArchivePreview> {
+    return this.archives.preview(request.user!, pondId, false);
+  }
+
+  /**
+   * The full archive: every readable page, EVERY attachment, and a versioned
+   * manifest with settings, labels, comments and the hierarchy (issue #305).
+   * Pond-Admin, because it is the deletion flow's last resort — a reader who
+   * wants their own copy has the Markdown export.
+   */
+  @Get('ponds/:pondId/archive')
+  @RequiresPondRole('pond_admin', { idParam: 'pondId' })
+  async pondArchive(
+    @Param('pondId') pondId: string,
+    @Req() request: AuthedRequest,
+    @Res() response: Response,
+  ): Promise<void> {
+    await this.archives.stream(request.user!, pondId, response, readActorOf(request), false);
+  }
 
   /** Streamed ZIP of the pond's readable pages as Markdown (+ `media/`). The
    * `reader` role is "may see the pond"; the service filters to readable pages,
@@ -48,3 +90,34 @@ export class ExportController {
     );
   }
 }
+
+/**
+ * The Site Admin's archive from the purge dialog (issue #305, #193).
+ *
+ * Separate controller because it must NOT carry `@RequiresPondRole`: a Site
+ * Admin purging a trashed pond is usually not a member of it, and the last
+ * archive before an irreversible purge must not depend on that. It is
+ * therefore complete by construction — the read filter is skipped.
+ */
+@Controller('admin/trash')
+@UseGuards(SiteAdminGuard)
+export class PondArchiveAdminController {
+  constructor(private readonly archives: PondArchiveService) {}
+
+  @Get('ponds/:pondId/archive/preview')
+  archivePreview(
+    @Param('pondId') pondId: string,
+    @Req() request: AuthedRequest,
+  ): Promise<PondArchivePreview> {
+    return this.archives.preview(request.user!, pondId, true);
+  }
+
+  @Get('ponds/:pondId/archive')
+  async archive(
+    @Param('pondId') pondId: string,
+    @Req() request: AuthedRequest,
+    @Res() response: Response,
+  ): Promise<void> {
+    await this.archives.stream(request.user!, pondId, response, readActorOf(request), true);
+  }
+}

apps/api/src/import-export/export.service.ts

@@ -6,6 +6,7 @@ import {
   ConversionJobView,
   ExportFormat,
   PondFonts,
+  customFontEntries,
   fontSlug,
   PageClassification,
   classificationMarking,
@@ -20,6 +21,7 @@ import { PinoLogger } from 'nestjs-pino';
 
 import { AppConfig } from '../config/app-config.service';
 import { FileStorageService } from '../files/file-storage.service';
+import { CustomFontsService } from '../fonts/custom-fonts.service';
 import { PermissionService } from '../permissions/permission.service';
 import { PluginFallbackRenderer } from '../plugins/plugin-fallback-renderer';
 import { PluginsService } from '../plugins/plugins.service';
@@ -53,6 +55,7 @@ export class ExportService {
     private readonly plugins: PluginsService,
     private readonly fallbacks: PluginFallbackRenderer,
     private readonly config: AppConfig,
+    private readonly customFonts: CustomFontsService,
     private readonly readTrail: ReadTrailService,
     private readonly logger: PinoLogger,
   ) {
@@ -333,6 +336,9 @@ export class ExportService {
       pondName: page.pond.name,
       bodyHtml,
       fonts,
+      // Both the rules and the stack need the uploaded families: embedding a
+      // face the stack never names would render the system font (issue #304).
+      customFonts: customFontEntries(await this.customFonts.list()),
       fontFaceCss: await this.fontFaceCss(fonts),
       // Styled sections keep their look in the PDF (#75); a pond without
       // active style plugins contributes an empty string.
@@ -371,12 +377,18 @@ export class ExportService {
     });
   }
 
-  /** Base64 `@font-face` rules for the pond's three fonts, read from the
-   * catalog baked into the image (ADR 0016). A font file that is absent (a
-   * native dev run without `FONTS_DIR` populated) is skipped — the render falls
-   * back to the system stack rather than failing. */
+  /** Base64 `@font-face` rules for the pond's three fonts. Catalog families
+   * come from the directory baked into the image (ADR 0016); operator-uploaded
+   * ones from `CUSTOM_FONTS_DIR` (issue #303) — same on-disk layout, so only
+   * the base directory differs. A font file that is absent (a native dev run
+   * without `FONTS_DIR` populated, or a family deleted between the settings
+   * write and the export) is skipped: the render falls back to the system
+   * stack rather than failing. */
   private async fontFaceCss(fonts: PondFonts): Promise<string> {
     const slots = [fonts.heading, fonts.body, fonts.mono];
+    const customSlugs = new Map(
+      (await this.customFonts.list()).map((font) => [font.family, font.slug]),
+    );
     // Dedup identical family+weight so a doc that repeats a font embeds it once.
     const seen = new Set<string>();
     const faces: string[] = [];
@@ -384,8 +396,10 @@ export class ExportService {
       const key = `${slot.family}:${slot.weight}`;
       if (seen.has(key)) continue;
       seen.add(key);
-      const slug = fontSlug(slot.family);
-      const file = join(this.config.env.FONTS_DIR, slug, `${slug}-${slot.weight}.woff2`);
+      const customSlug = customSlugs.get(slot.family);
+      const slug = customSlug ?? fontSlug(slot.family);
+      const baseDir = customSlug ? this.config.env.CUSTOM_FONTS_DIR : this.config.env.FONTS_DIR;
+      const file = join(baseDir, slug, `${slug}-${slot.weight}.woff2`);
       try {
         const bytes = await readFile(file);
         faces.push(
@@ -393,7 +407,7 @@ export class ExportService {
             ` src: url('data:font/woff2;base64,${bytes.toString('base64')}') format('woff2'); }`,
         );
       } catch {
-        this.logger.warn({ font: key }, 'pdf export: catalog font file missing, using fallback');
+        this.logger.warn({ font: key }, 'pdf export: font file missing, using fallback');
       }
     }
     return faces.join('\n');

apps/api/src/import-export/import-export.module.ts

@@ -2,6 +2,7 @@ import { Module, OnModuleInit } from '@nestjs/common';
 
 import { CommonModule } from '../common/common.module';
 import { FilesModule } from '../files/files.module';
+import { FontsModule } from '../fonts/fonts.module';
 import { LabelsModule } from '../labels/labels.module';
 import { PagesModule } from '../pages/pages.module';
 import { PluginsModule } from '../plugins/plugins.module';
@@ -14,7 +15,7 @@ import { ConversionWorker } from './conversion-worker.service';
 import { DATA_EXPORT_PROCESSOR } from './data-export.constants';
 import { DataExportController } from './data-export.controller';
 import { DataExportService } from './data-export.service';
-import { ExportController } from './export.controller';
+import { ExportController, PondArchiveAdminController } from './export.controller';
 import { ExportService } from './export.service';
 import { GotenbergHttpRenderer, GotenbergRenderer } from './gotenberg.renderer';
 import { IMPORT_PROCESSOR } from './import.constants';
@@ -22,6 +23,7 @@ import { ImportController } from './import.controller';
 import { ImportService } from './import.service';
 import { JobsController } from './jobs.controller';
 import { PandocConverter, PandocServerConverter } from './pandoc.converter';
+import { PondArchiveService } from './pond-archive.service';
 
 /** How often expired data-export payloads are purged (#68). Hourly is ample:
  * the link's own expiry check already stops downloads the moment it lapses. */
@@ -40,18 +42,26 @@ const PAYLOAD_PRUNE_CADENCE_SECONDS = 24 * 60 * 60;
   imports: [
     CommonModule,
     FilesModule,
+    FontsModule,
     LabelsModule,
     PagesModule,
     PluginsModule,
     SchedulerModule,
     SettingsModule,
   ],
-  controllers: [JobsController, ImportController, ExportController, DataExportController],
+  controllers: [
+    JobsController,
+    ImportController,
+    ExportController,
+    PondArchiveAdminController,
+    DataExportController,
+  ],
   providers: [
     ConversionJobService,
     ConversionWorker,
     ImportService,
     ExportService,
+    PondArchiveService,
     DataExportService,
     // The worker resolves the import pipeline through this token (never the
     // class), so its file does not import the import service's (avoids a cycle).

apps/api/src/import-export/pdf-html.test.ts

@@ -0,0 +1,51 @@
+import { DEFAULT_FONTS, customFontEntries } from '@dorfteich/shared';
+import { describe, expect, it } from 'vitest';
+
+import { buildPdfHtml } from './pdf-html';
+
+const CUSTOM = customFontEntries([
+  {
+    id: 'f1',
+    family: 'Corporate Grotesk',
+    slug: 'corporate-grotesk',
+    category: 'sans-serif',
+    licence: 'Bought from Foundry X',
+    licenceUrl: null,
+    weights: [400, 700],
+    createdAt: '2026-08-01T00:00:00.000Z',
+  },
+]);
+
+function base(family: string): Parameters<typeof buildPdfHtml>[0] {
+  return {
+    title: 'T',
+    pondName: 'P',
+    bodyHtml: '<p>x</p>',
+    fonts: { ...DEFAULT_FONTS, body: { family, weight: 400 } },
+    fontFaceCss: `@font-face { font-family: '${family}'; src: url('data:font/woff2;base64,AA'); }`,
+  };
+}
+
+describe('buildPdfHtml font stacks (issues #303/#304)', () => {
+  it('names an operator-uploaded family in the CSS stack when it is known', () => {
+    const html = buildPdfHtml({ ...base('Corporate Grotesk'), customFonts: CUSTOM });
+    expect(html).toContain("--font-body: 'Corporate Grotesk',");
+  });
+
+  /**
+   * The regression this pins: the `@font-face` rule for a custom family was
+   * embedded, but `fontStack` — not knowing the family — produced the bare
+   * system fallback, so the rule was never referenced and the PDF rendered in
+   * the system font while everything reported success.
+   */
+  it('would fall back to the system stack without the uploaded families', () => {
+    const html = buildPdfHtml(base('Corporate Grotesk'));
+    expect(html).not.toContain("'Corporate Grotesk',");
+    expect(html).toContain('--font-body: system-ui');
+  });
+
+  it('leaves catalog families working without any uploaded ones', () => {
+    const html = buildPdfHtml(base('Lora'));
+    expect(html).toContain("--font-body: 'Lora', Georgia");
+  });
+});

apps/api/src/import-export/pdf-html.ts

@@ -1,4 +1,4 @@
-import { PondFonts, fontStack } from '@dorfteich/shared';
+import { FontCatalogEntry, PondFonts, fontStack } from '@dorfteich/shared';
 
 export interface PdfHtmlParams {
   title: string;
@@ -8,6 +8,12 @@ export interface PdfHtmlParams {
   fonts: PondFonts;
   /** Pre-built `@font-face` rules (base64 WOFF2) for the pond's fonts. */
   fontFaceCss: string;
+  /** The instance's operator-uploaded families (issue #303), so a pond set to
+   * one gets it NAMED in the `font-family` stack. Without them `fontStack`
+   * cannot tell a custom family from a typo and yields the bare system
+   * fallback — the `@font-face` rule would then be embedded but never
+   * referenced, and the PDF would silently render in the system font. */
+  customFonts?: readonly FontCatalogEntry[];
   /** The pond's active section-style plugin CSS (issue #75), already validated
    * at install time (scoped selectors, no external fetches, no `</style>`).
    * Sections of a disabled plugin render neutrally — their class matches
@@ -35,6 +41,7 @@ function escapeHtml(value: string): string {
  */
 export function buildPdfHtml(params: PdfHtmlParams): string {
   const { fonts } = params;
+  const extra = params.customFonts ?? [];
   return `<!doctype html>
 <html lang="en">
 <head>
@@ -44,9 +51,9 @@ export function buildPdfHtml(params: PdfHtmlParams): string {
 ${params.fontFaceCss}
 @page { size: A4; }
 :root {
-  --font-heading: ${fontStack(fonts.heading.family)};
-  --font-body: ${fontStack(fonts.body.family)};
-  --font-mono: ${fontStack(fonts.mono.family)};
+  --font-heading: ${fontStack(fonts.heading.family, extra)};
+  --font-body: ${fontStack(fonts.body.family, extra)};
+  --font-mono: ${fontStack(fonts.mono.family, extra)};
 }
 html { font-size: 11pt; }
 body {

apps/api/src/import-export/pond-archive.e2e.db.test.ts

@@ -0,0 +1,250 @@
+import { INestApplication } from '@nestjs/common';
+import { PondArchiveManifest } from '@dorfteich/shared';
+import { PrismaClient } from '@prisma/client';
+import { unzipSync } from 'fflate';
+import request from 'supertest';
+import { afterAll, beforeAll, describe, expect, it } from 'vitest';
+
+import { AuthTokensService } from '../auth/auth-tokens.service';
+import { FilesService } from '../files/files.service';
+import { createTestApp, sessionCookieOf } from '../testing/test-app';
+import { createTestPrisma, deletePondsWhere, hasTestDb, uniqueSuffix } from '../testing/test-db';
+import { UsersService } from '../users/users.service';
+
+const PNG_BASE64 =
+  'iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAC0lEQVR42mP8z8BQDwAEhQGAhKmMIQAAAABJRU5ErkJggg==';
+
+function entries(buffer: Buffer): Record<string, Uint8Array> {
+  return unzipSync(new Uint8Array(buffer));
+}
+
+/** supertest parses text by default — a ZIP has to be collected as bytes. */
+function asBinary(req: request.Test): request.Test {
+  return req.parse((res, cb) => {
+    const chunks: Buffer[] = [];
+    res.on('data', (chunk: Buffer) => chunks.push(chunk));
+    res.on('end', () => cb(null, Buffer.concat(chunks)));
+  });
+}
+
+function manifestOf(buffer: Buffer): PondArchiveManifest {
+  const raw = entries(buffer)['manifest.json'];
+  return JSON.parse(Buffer.from(raw!).toString('utf8')) as PondArchiveManifest;
+}
+
+/**
+ * The full pond archive (issue #305). What separates it from the Markdown
+ * export is exactly what is asserted here: EVERY attachment travels, not only
+ * the embedded ones, and the manifest carries what Markdown cannot — settings,
+ * labels, comments and the hierarchy.
+ */
+describe.skipIf(!hasTestDb)('pond archive (e2e, issue #305)', () => {
+  let app: INestApplication;
+  let prisma: PrismaClient;
+  let files: FilesService;
+  const suffix = uniqueSuffix();
+  const password = 'archiviere den ganzen teich 1';
+  const owner = { username: `arch-${suffix}` };
+  const admin = { username: `archadm-${suffix}` };
+  let ownerId: string;
+  let ownerCookie: string;
+  let adminCookie: string;
+  let pondId: string;
+  let parentPageId: string;
+
+  const api = () => request(app.getHttpServer());
+
+  beforeAll(async () => {
+    prisma = createTestPrisma();
+    await prisma.rateLimit.deleteMany({});
+    app = await createTestApp();
+    files = app.get(FilesService);
+    const users = app.get(UsersService);
+    const tokens = app.get(AuthTokensService);
+
+    const ownerUser = await users.createUser({
+      username: owner.username,
+      email: `${owner.username}@example.org`,
+      displayName: `Archive Owner ${suffix}`,
+      password,
+      locale: 'en',
+    });
+    ownerId = ownerUser.id;
+    await api()
+      .post('/api/v1/auth/verify-email')
+      .send({ token: await tokens.issue(ownerUser.id, 'EMAIL_VERIFICATION', 600) })
+      .expect(204);
+    ownerCookie = sessionCookieOf(
+      await api()
+        .post('/api/v1/auth/login')
+        .send({ usernameOrEmail: owner.username, password })
+        .expect(200),
+    );
+
+    const adminUser = await users.createUser({
+      username: admin.username,
+      email: `${admin.username}@example.org`,
+      displayName: `Archive Admin ${suffix}`,
+      password,
+      locale: 'en',
+    });
+    await users.markEmailVerified(adminUser.id);
+    await prisma.user.update({ where: { id: adminUser.id }, data: { isSiteAdmin: true } });
+    adminCookie = sessionCookieOf(
+      await api()
+        .post('/api/v1/auth/login')
+        .send({ usernameOrEmail: admin.username, password })
+        .expect(200),
+    );
+
+    pondId = (await prisma.pond.findFirstOrThrow({ where: { ownerId, type: 'PERSONAL' } })).id;
+
+    // A parent and a child page, so the hierarchy has something to state.
+    const parent = await prisma.page.create({
+      data: {
+        pondId,
+        title: 'Archive Parent',
+        slug: 'archive-parent',
+        ydocState: new Uint8Array(),
+        sortKey: 'a',
+        createdBy: ownerId,
+        contentCache: {
+          create: { plainText: 'Parent body', markdown: 'Parent body', html: '', outline: [] },
+        },
+      },
+    });
+    parentPageId = parent.id;
+    await prisma.page.create({
+      data: {
+        pondId,
+        parentId: parent.id,
+        title: 'Archive Child',
+        slug: 'archive-child',
+        ydocState: new Uint8Array(),
+        sortKey: 'b',
+        createdBy: ownerId,
+        contentCache: {
+          create: { plainText: 'Child body', markdown: 'Child body', html: '', outline: [] },
+        },
+      },
+    });
+
+    const label = await prisma.label.create({
+      data: { pondId, name: `Archive Label ${suffix}`, color: '#2f6f4f' },
+    });
+    await prisma.pageLabel.create({ data: { pageId: parent.id, labelId: label.id } });
+    await prisma.comment.create({
+      data: { pageId: parent.id, authorId: ownerId, body: 'A remark worth keeping.' },
+    });
+  });
+
+  afterAll(async () => {
+    const where = { pond: { owner: { username: { contains: suffix } } } };
+    await prisma.comment.deleteMany({ where: { page: where } });
+    await prisma.attachment.deleteMany({ where });
+    await prisma.pageLabel.deleteMany({ where: { page: where } });
+    await prisma.label.deleteMany({ where });
+    await prisma.page.deleteMany({ where });
+    await prisma.roleGrant.deleteMany({ where });
+    await deletePondsWhere(prisma, { owner: { username: { contains: suffix } } });
+    await prisma.user.deleteMany({ where: { username: { contains: suffix } } });
+    await prisma.$disconnect();
+    await app.close();
+  });
+
+  it('contains EVERY attachment, not only the embedded ones', async () => {
+    // The gap this whole issue exists for: an attachment nobody embedded
+    // would vanish unnoticed with the Markdown export.
+    const orphan = await files.upload({ id: ownerId } as never, pondId, {
+      buffer: Buffer.from(PNG_BASE64, 'base64'),
+      size: 70,
+      originalname: 'never-embedded.png',
+    } as never);
+
+    const res = await asBinary(api().get(`/api/v1/ponds/${pondId}/archive`))
+      .set('Cookie', ownerCookie)
+      .expect(200);
+    expect(res.headers['content-type']).toContain('application/zip');
+
+    const names = Object.keys(entries(res.body as Buffer));
+    expect(names).toContain('manifest.json');
+    expect(names).toContain('README.txt');
+    expect(names).toContain('pages/archive-parent.md');
+    expect(names).toContain('pages/archive-child.md');
+    expect(names.some((name) => name.startsWith(`media/${orphan.id}.`))).toBe(true);
+
+    const manifest = manifestOf(res.body as Buffer);
+    expect(manifest.attachments.map((a) => a.id)).toContain(orphan.id);
+    // The Markdown export would have shipped no media at all here.
+    expect(manifest.attachments.length).toBeGreaterThan(0);
+  });
+
+  it('states the hierarchy, labels, comments and settings in the manifest', async () => {
+    const res = await asBinary(api().get(`/api/v1/ponds/${pondId}/archive`))
+      .set('Cookie', ownerCookie)
+      .expect(200);
+    const manifest = manifestOf(res.body as Buffer);
+
+    expect(manifest.kind).toBe('dorfteich-pond-archive');
+    expect(manifest.formatVersion).toBe(1);
+    expect(manifest.complete).toBe(true);
+    expect(manifest.omittedPages).toBe(0);
+
+    const child = manifest.pages.find((page) => page.slug === 'archive-child');
+    // The hierarchy is exactly what a folder of Markdown cannot express.
+    expect(child?.parentId).toBe(parentPageId);
+
+    expect(manifest.labels.some((label) => label.name.includes(suffix))).toBe(true);
+    expect(manifest.comments.map((comment) => comment.body)).toContain('A remark worth keeping.');
+    // A display name, not an account id — the archive outlives the account.
+    expect(manifest.comments[0]?.author).toContain('Archive Owner');
+    // Pond settings ride along; fonts are always present through the schema
+    // defaults, so their presence proves the settings object is real.
+    expect(manifest.pond.settings).toHaveProperty('fonts');
+  });
+
+  it('tells a requester before the download how much they would get', async () => {
+    const preview = await api()
+      .get(`/api/v1/ponds/${pondId}/archive/preview`)
+      .set('Cookie', ownerCookie)
+      .expect(200);
+    expect(preview.body.omittedPages).toBe(0);
+    expect(preview.body.includedPages).toBe(preview.body.totalPages);
+    expect(preview.body.complete).toBe(true);
+  });
+
+  it('audits the download with counts and completeness', async () => {
+    await asBinary(api().get(`/api/v1/ponds/${pondId}/archive`))
+      .set('Cookie', ownerCookie)
+      .expect(200);
+    const entry = await prisma.auditEntry.findFirst({
+      where: { action: 'pond.archived', targetId: pondId },
+      orderBy: { at: 'desc' },
+    });
+    expect(entry).not.toBeNull();
+    expect(entry!.details).toMatchObject({ complete: true, omittedPages: 0 });
+  });
+
+  it('gives the Site Admin a complete archive without pond membership', async () => {
+    // The purge dialog's archive must not depend on which ponds the operator
+    // happens to be a member of — this admin is a member of none.
+    const preview = await api()
+      .get(`/api/v1/admin/trash/ponds/${pondId}/archive/preview`)
+      .set('Cookie', adminCookie)
+      .expect(200);
+    expect(preview.body.complete).toBe(true);
+    expect(preview.body.omittedPages).toBe(0);
+
+    const res = await asBinary(api().get(`/api/v1/admin/trash/ponds/${pondId}/archive`))
+      .set('Cookie', adminCookie)
+      .expect(200);
+    expect(manifestOf(res.body as Buffer).pages.length).toBe(preview.body.totalPages);
+  });
+
+  it('keeps the admin archive away from an ordinary pond admin', async () => {
+    await api()
+      .get(`/api/v1/admin/trash/ponds/${pondId}/archive`)
+      .set('Cookie', ownerCookie)
+      .expect(403);
+  });
+});

apps/api/src/import-export/pond-archive.service.ts

@@ -0,0 +1,395 @@
+import { Injectable, NotFoundException } from '@nestjs/common';
+import {
+  PageClassification,
+  PondArchiveManifest,
+  PondArchivePreview,
+  POND_ARCHIVE_FORMAT_VERSION,
+  classificationMarking,
+  highestClassification,
+  pondSettingsSchema,
+} from '@dorfteich/shared';
+import { User } from '@prisma/client';
+import archiver from 'archiver';
+import type { Response } from 'express';
+import { PinoLogger } from 'nestjs-pino';
+
+import { AuditService } from '../audit/audit.service';
+import { FileStorageService } from '../files/file-storage.service';
+import { PermissionService } from '../permissions/permission.service';
+import { PrismaService } from '../prisma/prisma.service';
+import { ReadTrailService, type ReadActor } from '../read-trail/read-trail.service';
+
+import { markClassifiedMarkdown } from './classified-markdown';
+import { imageExtension, markdownForZip } from './export-markdown';
+
+/** The plain-text note that travels inside the ZIP. The manifest says the
+ *  same thing machine-readably, but a person unpacking a folder of Markdown
+ *  a year from now reads the file lying next to it — and must not believe
+ *  they are holding a one-click restore. */
+const README = `Dorfteich pond archive (format version ${POND_ARCHIVE_FORMAT_VERSION})
+
+This is a PRESERVATION archive, not a backup you can re-import: Dorfteich has
+no importer for it yet. Everything needed to write one later is here and
+documented — see manifest.json and docs/architecture/pond-archive-format.md in
+the Dorfteich repository.
+
+  manifest.json   pond settings, labels, page hierarchy, comments, attachment
+                  metadata, and the classification of every file
+  pages/          one Markdown file per page
+  media/          EVERY attachment of the pond, not only the embedded ones
+
+If manifest.json states "complete": false, the archive was produced by someone
+who could not read every page of the pond; "omittedPages" says how many are
+missing.
+`;
+
+/**
+ * The full pond archive offered before a pond is deleted (issue #305).
+ *
+ * Distinct from the Markdown export (`exportPond`, #65) on purpose: that one
+ * ships the pages plus the images they embed, which as a LAST resort is not
+ * enough — an attachment nobody embedded would vanish unnoticed. This one adds
+ * every attachment and a machine-readable sidecar of the things Markdown
+ * cannot carry: settings, labels, comments and the page hierarchy.
+ *
+ * Re-import is deliberately out of scope. The archive is a preservation
+ * format: complete, versioned and documented, so an importer can be written
+ * later without guesswork.
+ */
+@Injectable()
+export class PondArchiveService {
+  constructor(
+    private readonly prisma: PrismaService,
+    private readonly permissions: PermissionService,
+    private readonly storage: FileStorageService,
+    private readonly readTrail: ReadTrailService,
+    private readonly audit: AuditService,
+    private readonly logger: PinoLogger,
+  ) {
+    this.logger.setContext(PondArchiveService.name);
+  }
+
+  /**
+   * Pages in the pond and how many of them this requester may read.
+   *
+   * The UI states the difference BEFORE the download: an archive silently
+   * missing content is worse than no archive, because it ends the search.
+   * A site admin archiving from the purge dialog reads everything, so their
+   * preview says nothing is omitted.
+   */
+  async preview(user: User, pondId: string, unfiltered: boolean): Promise<PondArchivePreview> {
+    const pond = await this.loadPond(pondId);
+    const pages = await this.readablePages(user, pond.id, unfiltered);
+    const total = await this.prisma.page.count({ where: { pondId: pond.id, deletedAt: null } });
+    return {
+      totalPages: total,
+      includedPages: pages.length,
+      omittedPages: total - pages.length,
+      // "Complete" is a statement about the RESULT, not about the route: a
+      // pond admin who may read every page gets a complete archive too. Only
+      // an archive that actually leaves pages out is incomplete.
+      complete: total === pages.length,
+    };
+  }
+
+  /** The pond, or 404 — the caller's permission is checked by the route. */
+  private async loadPond(pondId: string): Promise<{ id: string; slug: string; name: string }> {
+    // Deliberately including trashed ponds: the purge dialog archives a pond
+    // that is already in the trash, which is the last moment it exists.
+    const pond = await this.prisma.pond.findUnique({
+      where: { id: pondId },
+      select: { id: true, slug: true, name: true },
+    });
+    if (!pond) throw new NotFoundException();
+    return pond;
+  }
+
+  private async readablePages(
+    user: User,
+    pondId: string,
+    unfiltered: boolean,
+  ): Promise<
+    {
+      id: string;
+      slug: string;
+      title: string;
+      parentId: string | null;
+      sortKey: string;
+      classification: string;
+      createdAt: Date;
+      updatedAt: Date;
+      labels: { labelId: string }[];
+      contentCache: { markdown: string } | null;
+    }[]
+  > {
+    const pages = await this.prisma.page.findMany({
+      where: { pondId, deletedAt: null },
+      orderBy: { title: 'asc' },
+      select: {
+        id: true,
+        slug: true,
+        title: true,
+        parentId: true,
+        sortKey: true,
+        classification: true,
+        createdAt: true,
+        updatedAt: true,
+        labels: { select: { labelId: true } },
+        contentCache: { select: { markdown: true } },
+      },
+    });
+    if (unfiltered) return pages;
+    const readable = await this.permissions.filterPages(
+      user,
+      pondId,
+      pages.map((page) => ({ id: page.id, labelIds: page.labels.map((l) => l.labelId) })),
+      'read',
+    );
+    return pages.filter((page) => readable.has(page.id));
+  }
+
+  /**
+   * Stream the archive.
+   *
+   * `unfiltered` is the Site-Admin path from the purge dialog: it skips the
+   * read filter, because the last archive before an irreversible purge must
+   * not depend on which pages the operator happens to be a member of.
+   * Whether the RESULT is complete is a separate question, answered by
+   * comparing what went in with what exists.
+   */
+  async stream(
+    user: User,
+    pondId: string,
+    res: Response,
+    read: ReadActor,
+    unfiltered: boolean,
+  ): Promise<void> {
+    const pond = await this.loadPond(pondId);
+    const pages = await this.readablePages(user, pond.id, unfiltered);
+    const totalPages = await this.prisma.page.count({
+      where: { pondId: pond.id, deletedAt: null },
+    });
+    const complete = totalPages === pages.length;
+
+    // Read trail (ADR 0023, issue #222's property): one `export` event per
+    // classified page BEFORE any classified byte enters the stream, so a
+    // failed write aborts the download with the evidence intact. The added
+    // attachments carry their page's classification and are covered by the
+    // same events — they never travel without their page.
+    for (const page of pages) {
+      if (page.classification !== 'VS_NFD') continue;
+      await this.readTrail.record({
+        ...read,
+        pageId: page.id,
+        pondId: pond.id,
+        channel: 'export',
+        details: { format: 'pond_archive' },
+      });
+    }
+
+    const [settingsRow, labels, comments, attachmentRows] = await Promise.all([
+      this.prisma.pond.findUniqueOrThrow({
+        where: { id: pond.id },
+        select: { name: true, slug: true, type: true, settings: true, createdAt: true },
+      }),
+      this.prisma.label.findMany({
+        where: { pondId: pond.id },
+        select: { id: true, name: true, color: true, parentId: true },
+        orderBy: { name: 'asc' },
+      }),
+      this.prisma.comment.findMany({
+        where: { page: { pondId: pond.id, deletedAt: null } },
+        orderBy: { createdAt: 'asc' },
+        select: {
+          id: true,
+          pageId: true,
+          parentId: true,
+          body: true,
+          createdAt: true,
+          editedAt: true,
+          resolvedAt: true,
+          author: { select: { displayName: true } },
+        },
+      }),
+      // EVERY attachment of the pond (issue #305) — not only the embedded
+      // ones the Markdown export ships.
+      this.prisma.attachment.findMany({
+        where: { pondId: pond.id },
+        select: {
+          id: true,
+          pageId: true,
+          fileName: true,
+          mimeType: true,
+          sizeBytes: true,
+          sha256: true,
+          createdAt: true,
+        },
+        orderBy: { createdAt: 'asc' },
+      }),
+    ]);
+
+    const includedPageIds = new Set(pages.map((page) => page.id));
+    // An attachment of a page the requester cannot read stays out — the same
+    // rule the pages follow. Pond-level attachments (no page) are included:
+    // nothing narrower than the pond governs them.
+    const visibleAttachments = attachmentRows.filter(
+      (row) => !row.pageId || includedPageIds.has(row.pageId),
+    );
+    const onDisk = await Promise.all(
+      visibleAttachments.map((row) => this.storage.exists(pond.id, row.id)),
+    );
+    const attachments = visibleAttachments.filter((_, index) => onDisk[index]);
+
+    const classificationByPage = new Map(
+      pages.map((page) => [page.id, page.classification.toLowerCase() as PageClassification]),
+    );
+    const mediaName = new Map(
+      attachments.map((row) => [row.id, `${row.id}.${imageExtension(row.mimeType)}`]),
+    );
+    const readableSlugs = new Set(pages.map((page) => page.slug));
+
+    const archive = archiver('zip', { zlib: { level: 9 } });
+    res.set('Content-Type', 'application/zip');
+    res.set('Content-Disposition', `attachment; filename="${pond.slug}-archive.zip"`);
+    res.set('X-Content-Type-Options', 'nosniff');
+    archive.on('error', (error) => {
+      this.logger.error({ pondId: pond.id, err: error.message }, 'pond archive failed');
+      res.destroy(error);
+    });
+    archive.pipe(res);
+
+    const files: { path: string; classification: PageClassification }[] = [];
+
+    for (const page of pages) {
+      const level = classificationByPage.get(page.id) ?? 'unclassified';
+      const markdown = markClassifiedMarkdown(
+        markdownForZip(page.contentCache?.markdown ?? '', readableSlugs, mediaName),
+        level,
+      );
+      const path = `pages/${page.slug}.md`;
+      archive.append(markdown, { name: path });
+      files.push({ path, classification: level });
+    }
+
+    for (const row of attachments) {
+      // An attachment inherits its page's level (fail-closed, ADR 0022); one
+      // that belongs to no page inherits the pond's highest, because nothing
+      // narrower governs it.
+      const level = row.pageId
+        ? (classificationByPage.get(row.pageId) ?? 'unclassified')
+        : highestClassification([...classificationByPage.values()]);
+      const path = `media/${mediaName.get(row.id)!}`;
+      files.push({ path, classification: level });
+      // Companion marking (issue #212): binaries cannot carry it themselves,
+      // and the sibling file survives unpacking where a manifest may not.
+      const marking = classificationMarking(level);
+      if (marking) {
+        archive.append(`${marking}\n`, { name: `${path}.classification.txt` });
+        files.push({ path: `${path}.classification.txt`, classification: level });
+      }
+    }
+
+    const manifest: PondArchiveManifest = {
+      kind: 'dorfteich-pond-archive',
+      formatVersion: POND_ARCHIVE_FORMAT_VERSION,
+      exportedAt: new Date().toISOString(),
+      complete,
+      omittedPages: totalPages - pages.length,
+      classification: highestClassification(files.map((file) => file.classification)),
+      pond: {
+        name: settingsRow.name,
+        slug: settingsRow.slug,
+        type: settingsRow.type,
+        createdAt: settingsRow.createdAt.toISOString(),
+        // The EFFECTIVE settings, defaults filled in — a preservation format
+        // must not require its reader to know Dorfteich's defaults, and the
+        // stored row only holds what was explicitly set.
+        settings: pondSettingsSchema.parse(settingsRow.settings ?? {}) as unknown as Record<
+          string,
+          unknown
+        >,
+      },
+      labels: labels.map((label) => ({
+        id: label.id,
+        name: label.name,
+        color: label.color,
+        parentId: label.parentId,
+      })),
+      pages: pages.map((page) => ({
+        id: page.id,
+        slug: page.slug,
+        title: page.title,
+        parentId: page.parentId,
+        sortKey: page.sortKey,
+        classification: page.classification.toLowerCase() as PageClassification,
+        labelIds: page.labels.map((label) => label.labelId),
+        createdAt: page.createdAt.toISOString(),
+        updatedAt: page.updatedAt.toISOString(),
+        file: `pages/${page.slug}.md`,
+      })),
+      // Comments of included pages only — a comment is content of its page.
+      comments: comments
+        .filter((comment) => includedPageIds.has(comment.pageId))
+        .map((comment) => ({
+          id: comment.id,
+          pageId: comment.pageId,
+          parentId: comment.parentId,
+          body: comment.body,
+          // The display name, not the account: the archive is a document, and
+          // it should stay readable after the account is gone.
+          author: comment.author?.displayName ?? null,
+          createdAt: comment.createdAt.toISOString(),
+          editedAt: comment.editedAt?.toISOString() ?? null,
+          resolvedAt: comment.resolvedAt?.toISOString() ?? null,
+        })),
+      attachments: attachments.map((row) => ({
+        id: row.id,
+        pageId: row.pageId,
+        fileName: row.fileName,
+        mimeType: row.mimeType,
+        sizeBytes: row.sizeBytes,
+        sha256: row.sha256,
+        createdAt: row.createdAt.toISOString(),
+        file: `media/${mediaName.get(row.id)!}`,
+      })),
+      files,
+    };
+
+    archive.append(README, { name: 'README.txt' });
+    archive.append(JSON.stringify(manifest, null, 2), { name: 'manifest.json' });
+
+    for (const row of attachments) {
+      const stream = this.storage.createReadStream(pond.id, row.id);
+      stream.on('error', (error) =>
+        this.logger.warn(
+          { pondId: pond.id, fileId: row.id, err: error.message },
+          'pond archive: media read failed',
+        ),
+      );
+      archive.append(stream, { name: `media/${mediaName.get(row.id)!}` });
+    }
+
+    // Audited: a whole pond leaving the instance in one file, usually right
+    // before it is deleted, is exactly the event an operator wants to find
+    // later. Recorded before finalize so the trail exists even if the
+    // download is aborted mid-stream.
+    await this.audit.record({
+      action: 'pond.archived',
+      actorId: user.id,
+      targetType: 'pond',
+      targetId: pond.id,
+      details: {
+        pages: pages.length,
+        attachments: attachments.length,
+        omittedPages: totalPages - pages.length,
+        complete,
+      },
+    });
+
+    await archive.finalize();
+    this.logger.info(
+      { pondId: pond.id, pages: pages.length, attachments: attachments.length, complete },
+      'pond archive streamed',
+    );
+  }
+}

apps/api/src/invitations/invitations.controller.ts

@@ -0,0 +1,50 @@
+import { Body, Controller, Delete, Get, HttpCode, Param, Post, Req } from '@nestjs/common';
+import {
+  CreateInvitationInput,
+  InvitationListView,
+  InvitationPreview,
+  InvitationView,
+  createInvitationSchema,
+  invitationPreviewSchema,
+} from '@dorfteich/shared';
+
+import { AuthedRequest, Public } from '../auth/auth.guard';
+import { ZodValidationPipe } from '../common/zod-validation.pipe';
+import { AuthenticatedOnly } from '../permissions/permission.decorators';
+import { InvitationsService } from './invitations.service';
+
+/** Peer invitations (issue #332). */
+@AuthenticatedOnly()
+@Controller('invitations')
+export class InvitationsController {
+  constructor(private readonly invitations: InvitationsService) {}
+
+  @Post()
+  async create(
+    @Body(new ZodValidationPipe(createInvitationSchema)) input: CreateInvitationInput,
+    @Req() request: AuthedRequest,
+  ): Promise<InvitationView> {
+    return this.invitations.create(request.user!, input.email);
+  }
+
+  @Get()
+  async list(@Req() request: AuthedRequest): Promise<InvitationListView> {
+    return this.invitations.list(request.user!);
+  }
+
+  @Delete(':id')
+  @HttpCode(204)
+  async revoke(@Param('id') id: string, @Req() request: AuthedRequest): Promise<void> {
+    await this.invitations.revoke(request.user!, id);
+  }
+
+  /** The signup screen's link check — POST keeps the token out of logs. */
+  @Public()
+  @Post('preview')
+  @HttpCode(200)
+  async preview(
+    @Body(new ZodValidationPipe(invitationPreviewSchema)) input: { token: string },
+  ): Promise<InvitationPreview> {
+    return this.invitations.preview(input.token);
+  }
+}

apps/api/src/invitations/invitations.e2e.db.test.ts

@@ -0,0 +1,246 @@
+import { INestApplication } from '@nestjs/common';
+import { InvitationListView, InvitationPreview, InvitationView } from '@dorfteich/shared';
+import { PrismaClient } from '@prisma/client';
+import request from 'supertest';
+import { afterAll, beforeAll, describe, expect, it } from 'vitest';
+
+import { InstanceSettingsService } from '../settings/instance-settings.service';
+import { createTestApp, sessionCookieOf } from '../testing/test-app';
+import { createTestPrisma, deletePondsWhere, hasTestDb, uniqueSuffix } from '../testing/test-db';
+import { UsersService } from '../users/users.service';
+
+/**
+ * Peer invitations end to end (issue #332): inviting mails a single-use
+ * link, open invitations are quota-bound per user, and a valid token lets
+ * exactly one signup through a closed registration. Settings written here
+ * are restored inside each test and the keys are deleted in afterAll
+ * (shared-DB rule).
+ */
+describe.skipIf(!hasTestDb)('invitations (e2e, issue #332)', () => {
+  let app: INestApplication;
+  let prisma: PrismaClient;
+  const suffix = uniqueSuffix();
+  const password = 'einladungen sind praktisch 1';
+  const ids: Record<string, string> = {};
+  const cookies: Record<string, string> = {};
+
+  const api = () => request(app.getHttpServer());
+  const settings = () => app.get(InstanceSettingsService);
+
+  async function makeUser(handle: string): Promise<void> {
+    const users = app.get(UsersService);
+    const username = `inv-${handle}-${suffix}`;
+    const user = await users.createUser({
+      username,
+      email: `${username}@example.org`,
+      displayName: `Inv ${handle}`,
+      password,
+      locale: 'en',
+    });
+    await users.markEmailVerified(user.id);
+    ids[handle] = user.id;
+    cookies[handle] = sessionCookieOf(
+      await api()
+        .post('/api/v1/auth/login')
+        .send({ usernameOrEmail: username, password })
+        .expect(200),
+    );
+  }
+
+  /** The raw token only travels in the mail — fish it out of the outbox. */
+  async function mailedTokenFor(email: string): Promise<string> {
+    const mail = await prisma.mailOutbox.findFirstOrThrow({
+      where: { toAddress: email },
+      orderBy: { createdAt: 'desc' },
+    });
+    const match = /invitation=([A-Za-z0-9_-]+)/.exec(mail.textBody);
+    expect(match).not.toBeNull();
+    return match![1]!;
+  }
+
+  beforeAll(async () => {
+    prisma = createTestPrisma();
+    await prisma.rateLimit.deleteMany({});
+    app = await createTestApp();
+    await makeUser('alice');
+    await makeUser('quota');
+  });
+
+  afterAll(async () => {
+    await prisma.instanceSetting.deleteMany({
+      where: { key: { in: ['auth.registrationMode', 'invitations.maxOpenPerUser'] } },
+    });
+    const all = Object.values(ids);
+    await prisma.invitation.deleteMany({ where: { inviterId: { in: all } } });
+    await prisma.mailOutbox.deleteMany({ where: { toAddress: { contains: suffix } } });
+    await prisma.session.deleteMany({ where: { userId: { in: all } } });
+    await deletePondsWhere(prisma, { ownerId: { in: all } });
+    await prisma.userIdentity.deleteMany({ where: { userId: { in: all } } });
+    await prisma.user.deleteMany({ where: { id: { in: all } } });
+    await prisma.$disconnect();
+    await app.close();
+  });
+
+  it('invites, lists, and mails a single-use signup link', async () => {
+    const invitee = `guest-${suffix}@example.org`;
+    const res = await api()
+      .post('/api/v1/invitations')
+      .set('Cookie', cookies.alice!)
+      .send({ email: invitee })
+      .expect(201);
+    const view = res.body as InvitationView;
+    expect(view.status).toBe('pending');
+
+    const list = (await api().get('/api/v1/invitations').set('Cookie', cookies.alice!).expect(200))
+      .body as InvitationListView;
+    expect(list.open).toBe(1);
+    expect(list.maxOpen).toBe(5);
+    expect(list.invitations.map((i) => i.id)).toContain(view.id);
+
+    // The mail exists and the public preview identifies the inviter.
+    const token = await mailedTokenFor(invitee);
+    const preview = (await api().post('/api/v1/invitations/preview').send({ token }).expect(200))
+      .body as InvitationPreview;
+    expect(preview.email).toBe(invitee);
+    expect(preview.inviterName).toBe('Inv alice');
+  });
+
+  it('a valid token passes a closed registration exactly once; a burned signup attempt does not consume it', async () => {
+    const invitee = `joiner-${suffix}@example.org`;
+    await api()
+      .post('/api/v1/invitations')
+      .set('Cookie', cookies.alice!)
+      .send({ email: invitee })
+      .expect(201);
+    const token = await mailedTokenFor(invitee);
+
+    await settings().set('auth.registrationMode', 'closed', ids.alice!);
+    try {
+      // Closed without a token: refused.
+      await api()
+        .post('/api/v1/auth/signup')
+        .send({
+          username: `inv-blocked-${suffix}`,
+          email: `inv-blocked-${suffix}@example.org`,
+          displayName: 'Blocked',
+          password,
+          locale: 'en',
+        })
+        .expect(403);
+
+      // A failing signup (taken username) must NOT burn the token.
+      await api()
+        .post('/api/v1/auth/signup')
+        .send({
+          username: `inv-alice-${suffix}`, // taken
+          email: invitee,
+          displayName: 'Joiner',
+          password,
+          locale: 'en',
+          invitationToken: token,
+        })
+        .expect(409);
+
+      // Same link, fresh username: through, despite closed mode.
+      const username = `inv-joiner-${suffix}`;
+      await api()
+        .post('/api/v1/auth/signup')
+        .send({
+          username,
+          email: invitee,
+          displayName: 'Joiner',
+          password,
+          locale: 'en',
+          invitationToken: token,
+        })
+        .expect(201);
+      const joiner = await prisma.user.findUniqueOrThrow({ where: { username } });
+      ids.joiner = joiner.id;
+
+      // The invitation is tied to the new account…
+      const accepted = await prisma.invitation.findFirstOrThrow({
+        where: { acceptedUserId: joiner.id },
+      });
+      expect(accepted.acceptedAt).not.toBeNull();
+
+      // …and the token is single-use.
+      await api()
+        .post('/api/v1/auth/signup')
+        .send({
+          username: `inv-replay-${suffix}`,
+          email: `inv-replay-${suffix}@example.org`,
+          displayName: 'Replay',
+          password,
+          locale: 'en',
+          invitationToken: token,
+        })
+        .expect(400);
+    } finally {
+      await settings().set('auth.registrationMode', 'open', ids.alice!);
+    }
+  });
+
+  it('enforces the open-invitations quota and frees it on revoke', async () => {
+    await settings().set('invitations.maxOpenPerUser', 2, ids.alice!);
+    try {
+      const first = (
+        await api()
+          .post('/api/v1/invitations')
+          .set('Cookie', cookies.quota!)
+          .send({ email: `q1-${suffix}@example.org` })
+          .expect(201)
+      ).body as InvitationView;
+      await api()
+        .post('/api/v1/invitations')
+        .set('Cookie', cookies.quota!)
+        .send({ email: `q2-${suffix}@example.org` })
+        .expect(201);
+      await api()
+        .post('/api/v1/invitations')
+        .set('Cookie', cookies.quota!)
+        .send({ email: `q3-${suffix}@example.org` })
+        .expect(400)
+        .expect((r) => expect((r.body as { code: string }).code).toBe('invitation_quota_reached'));
+
+      // Revoking an open invitation frees the slot…
+      await api()
+        .delete(`/api/v1/invitations/${first.id}`)
+        .set('Cookie', cookies.quota!)
+        .expect(204);
+      await api()
+        .post('/api/v1/invitations')
+        .set('Cookie', cookies.quota!)
+        .send({ email: `q3-${suffix}@example.org` })
+        .expect(201);
+
+      // …and the revoked token is dead.
+      const revokedToken = await mailedTokenFor(`q1-${suffix}@example.org`);
+      await api().post('/api/v1/invitations/preview').send({ token: revokedToken }).expect(400);
+    } finally {
+      await settings().set('invitations.maxOpenPerUser', 5, ids.alice!);
+    }
+  });
+
+  it('quota 0 disables inviting entirely', async () => {
+    await settings().set('invitations.maxOpenPerUser', 0, ids.alice!);
+    try {
+      await api()
+        .post('/api/v1/invitations')
+        .set('Cookie', cookies.alice!)
+        .send({ email: `off-${suffix}@example.org` })
+        .expect(403)
+        .expect((r) => expect((r.body as { code: string }).code).toBe('invitations_disabled'));
+    } finally {
+      await settings().set('invitations.maxOpenPerUser', 5, ids.alice!);
+    }
+  });
+
+  it('requires a session for create/list/revoke but not for preview', async () => {
+    await api().post('/api/v1/invitations').send({ email: 'nope@example.org' }).expect(401);
+    await api().get('/api/v1/invitations').expect(401);
+    await api()
+      .post('/api/v1/invitations/preview')
+      .send({ token: 'x'.repeat(32) })
+      .expect(400);
+  });
+});

apps/api/src/invitations/invitations.module.ts

@@ -0,0 +1,13 @@
+import { Module } from '@nestjs/common';
+
+import { MailModule } from '../mail/mail.module';
+import { InvitationsController } from './invitations.controller';
+import { InvitationsService } from './invitations.service';
+
+@Module({
+  imports: [MailModule],
+  controllers: [InvitationsController],
+  providers: [InvitationsService],
+  exports: [InvitationsService],
+})
+export class InvitationsModule {}

apps/api/src/invitations/invitations.service.ts

@@ -0,0 +1,199 @@
+import { createHash, randomBytes } from 'node:crypto';
+
+import {
+  BadRequestException,
+  ForbiddenException,
+  HttpException,
+  HttpStatus,
+  Injectable,
+  NotFoundException,
+} from '@nestjs/common';
+import {
+  InvitationListView,
+  InvitationPreview,
+  InvitationStatus,
+  InvitationView,
+} from '@dorfteich/shared';
+import { Invitation, User } from '@prisma/client';
+
+import { AuditService } from '../audit/audit.service';
+import { AppConfig } from '../config/app-config.service';
+import { MailService } from '../mail/mail.service';
+import { PrismaService } from '../prisma/prisma.service';
+import { RateLimitService } from '../rate-limit/rate-limit.service';
+import { InstanceSettingsService } from '../settings/instance-settings.service';
+
+export const INVITATION_TTL_SECONDS = 14 * 24 * 60 * 60;
+
+// Anti-spam backstop besides the open-invitations quota: without it a
+// revoke-and-recreate loop would allow unlimited mail volume while never
+// exceeding the quota.
+const CREATE_LIMIT = { limit: 20, windowSeconds: 24 * 60 * 60 };
+
+/**
+ * Peer invitations (issue #332). A user invites an e-mail address; the
+ * mailed single-use token lets exactly one signup through even while
+ * registration is closed (auth.service). Open (pending, unexpired)
+ * invitations count against the per-user quota
+ * `invitations.maxOpenPerUser` — 0 turns the feature off. Only the
+ * SHA-256 hash of the token is stored (auth-tokens pattern); revoked and
+ * accepted rows are kept so the settings UI can show history.
+ */
+@Injectable()
+export class InvitationsService {
+  constructor(
+    private readonly prisma: PrismaService,
+    private readonly mail: MailService,
+    private readonly rateLimits: RateLimitService,
+    private readonly settings: InstanceSettingsService,
+    private readonly audit: AuditService,
+    private readonly config: AppConfig,
+  ) {}
+
+  async create(user: User, email: string): Promise<InvitationView> {
+    const maxOpen = (await this.settings.get('invitations.maxOpenPerUser')) as number;
+    if (maxOpen === 0) throw new ForbiddenException({ code: 'invitations_disabled' });
+    if ((await this.openCount(user.id)) >= maxOpen) {
+      throw new BadRequestException({ code: 'invitation_quota_reached' });
+    }
+    const limit = await this.rateLimits.hit(
+      'invitation-create',
+      user.id,
+      CREATE_LIMIT.limit,
+      CREATE_LIMIT.windowSeconds,
+    );
+    if (!limit.allowed) {
+      throw new HttpException({ code: 'rate_limited' }, HttpStatus.TOO_MANY_REQUESTS);
+    }
+
+    const raw = randomBytes(32).toString('base64url');
+    const row = await this.prisma.invitation.create({
+      data: {
+        inviterId: user.id,
+        email: email.toLowerCase(),
+        tokenHash: hashToken(raw),
+        expiresAt: new Date(Date.now() + INVITATION_TTL_SECONDS * 1000),
+      },
+    });
+    // The invitee has no account and no locale yet — the instance default
+    // decides the mail language. The greeting falls back to the address.
+    await this.mail.enqueue(
+      row.email,
+      'invitation',
+      {
+        displayName: row.email,
+        inviterName: user.displayName,
+        link: `${this.config.env.APP_BASE_URL}/signup?invitation=${raw}`,
+      },
+      (await this.settings.get('instance.defaultLocale')) as 'de' | 'en',
+    );
+    await this.audit.record({
+      action: 'invitation.created',
+      actorId: user.id,
+      targetType: 'invitation',
+      targetId: row.id,
+    });
+    return this.viewOf(row);
+  }
+
+  async list(user: User): Promise<InvitationListView> {
+    const rows = await this.prisma.invitation.findMany({
+      where: { inviterId: user.id },
+      orderBy: { createdAt: 'desc' },
+      take: 100,
+    });
+    return {
+      invitations: rows.map((row) => this.viewOf(row)),
+      open: await this.openCount(user.id),
+      maxOpen: (await this.settings.get('invitations.maxOpenPerUser')) as number,
+    };
+  }
+
+  async revoke(user: User, id: string): Promise<void> {
+    const row = await this.prisma.invitation.findFirst({
+      where: { id, inviterId: user.id },
+    });
+    if (!row) throw new NotFoundException();
+    if (row.acceptedAt) throw new BadRequestException({ code: 'invitation_already_accepted' });
+    if (row.revokedAt) return; // idempotent
+    await this.prisma.invitation.update({ where: { id }, data: { revokedAt: new Date() } });
+    await this.audit.record({
+      action: 'invitation.revoked',
+      actorId: user.id,
+      targetType: 'invitation',
+      targetId: id,
+    });
+  }
+
+  /** What the signup screen may show for a link before it is used. */
+  async preview(raw: string): Promise<InvitationPreview> {
+    const row = await this.prisma.invitation.findUnique({
+      where: { tokenHash: hashToken(raw) },
+      include: { inviter: true },
+    });
+    if (!row || row.revokedAt || row.acceptedAt || row.expiresAt <= new Date()) {
+      throw new BadRequestException({ code: 'token_invalid' });
+    }
+    return { email: row.email, inviterName: row.inviter.displayName };
+  }
+
+  /**
+   * Atomically claims the token (only one signup can flip acceptedAt from
+   * null). Returns the row, or null for unknown/revoked/expired/used
+   * tokens. The caller un-redeems if the signup fails afterwards.
+   */
+  async redeem(raw: string): Promise<Invitation | null> {
+    const result = await this.prisma.invitation.updateMany({
+      where: {
+        tokenHash: hashToken(raw),
+        revokedAt: null,
+        acceptedAt: null,
+        expiresAt: { gt: new Date() },
+      },
+      data: { acceptedAt: new Date() },
+    });
+    if (result.count === 0) return null;
+    return this.prisma.invitation.findUnique({ where: { tokenHash: hashToken(raw) } });
+  }
+
+  /** Ties the redeemed invitation to the account it created. */
+  async markAccepted(id: string, userId: string): Promise<void> {
+    await this.prisma.invitation.update({ where: { id }, data: { acceptedUserId: userId } });
+  }
+
+  /** Rolls a redeem back when the signup it gated failed (e.g. duplicate
+   * username) — the invitee must be able to try again with the same link. */
+  async unredeem(id: string): Promise<void> {
+    await this.prisma.invitation.updateMany({
+      where: { id, acceptedUserId: null },
+      data: { acceptedAt: null },
+    });
+  }
+
+  private openCount(inviterId: string): Promise<number> {
+    return this.prisma.invitation.count({
+      where: { inviterId, revokedAt: null, acceptedAt: null, expiresAt: { gt: new Date() } },
+    });
+  }
+
+  private viewOf(row: Invitation): InvitationView {
+    return {
+      id: row.id,
+      email: row.email,
+      status: statusOf(row),
+      createdAt: row.createdAt.toISOString(),
+      expiresAt: row.expiresAt.toISOString(),
+    };
+  }
+}
+
+function statusOf(row: Invitation): InvitationStatus {
+  if (row.revokedAt) return 'revoked';
+  if (row.acceptedAt) return 'accepted';
+  if (row.expiresAt <= new Date()) return 'expired';
+  return 'pending';
+}
+
+function hashToken(raw: string): string {
+  return createHash('sha256').update(raw).digest('hex');
+}

apps/api/src/mail/mail-templates.ts

@@ -1,6 +1,6 @@
 import { apiI18n } from '../i18n/api-i18n';
 
-export type MailTemplate = 'verifyEmail' | 'resetPassword' | 'smtpTest';
+export type MailTemplate = 'verifyEmail' | 'resetPassword' | 'smtpTest' | 'invitation';
 
 export interface RenderedMail {
   subject: string;
@@ -15,14 +15,15 @@ export interface RenderedMail {
  */
 export function renderMail(
   template: MailTemplate,
-  params: { displayName: string; link: string },
+  // Extra keys (e.g. inviterName, #332) interpolate into the body text.
+  params: { displayName: string; link: string } & Record<string, string>,
   locale: 'de' | 'en',
 ): RenderedMail {
   const t = (key: string, options: Record<string, string> = {}): string =>
     apiI18n.t(`mails:${key}`, { lng: locale, ...options });
 
   const greeting = t('common.greeting', { displayName: params.displayName });
-  const body = t(`${template}.body`);
+  const body = t(`${template}.body`, params);
   const action = t(`${template}.action`);
   const expiry = t(`${template}.expiry`);
   const ignore = t('common.ignoreHint');

apps/api/src/mail/mail.service.ts

@@ -14,7 +14,7 @@ export class MailService {
   async enqueue(
     to: string,
     template: MailTemplate,
-    params: { displayName: string; link: string },
+    params: { displayName: string; link: string } & Record<string, string>,
     locale: 'de' | 'en',
   ): Promise<void> {
     const rendered = renderMail(template, params, locale);

apps/api/src/members/members.e2e.db.test.ts

@@ -6,7 +6,7 @@ import { afterAll, beforeAll, describe, expect, it } from 'vitest';
 
 import { PondsService } from '../ponds/ponds.service';
 import { createTestApp, sessionCookieOf } from '../testing/test-app';
-import { createTestPrisma, hasTestDb, uniqueSuffix } from '../testing/test-db';
+import { createTestPrisma, deletePondsWhere, hasTestDb, uniqueSuffix } from '../testing/test-db';
 import { UsersService } from '../users/users.service';
 
 /**
@@ -97,7 +97,7 @@ describe.skipIf(!hasTestDb)('pond members (e2e, issue #54)', () => {
     const ids = Object.values(userIds);
     await prisma.roleGrant.deleteMany({ where: { pond: { ownerId: { in: ids } } } });
     await prisma.quotaOverride.deleteMany({ where: { subjectId: { in: [...ids, pondId] } } });
-    await prisma.pond.deleteMany({ where: { ownerId: { in: ids } } });
+    await deletePondsWhere(prisma, { ownerId: { in: ids } });
     await prisma.user.deleteMany({ where: { id: { in: ids } } });
     await prisma.$disconnect();
     await app.close();

apps/api/src/notifications/unsubscribe-token.test.ts

@@ -3,11 +3,7 @@ import { createHmac } from 'node:crypto';
 import { deriveTokenKey } from '@dorfteich/shared/token-crypto';
 import { describe, expect, it } from 'vitest';
 
-import {
-  LEGACY_VERIFY_UNTIL,
-  signUnsubscribeToken,
-  verifyUnsubscribeToken,
-} from './unsubscribe-token';
+import { signUnsubscribeToken, verifyUnsubscribeToken } from './unsubscribe-token';
 
 const secret = 'test-secret-at-least-16-chars-long';
 const TTL_MS = 90 * 24 * 60 * 60 * 1000;
@@ -50,23 +46,15 @@ describe('unsubscribe token', () => {
     expect(verifyUnsubscribeToken(`${body}.${sig}`, secret)).toBeNull();
   });
 
-  it('accepts a pre-separation legacy token inside the dual-verify window', () => {
-    const inWindow = LEGACY_VERIFY_UNTIL - 24 * 60 * 60 * 1000;
-    expect(verifyUnsubscribeToken(legacyToken('u1', inWindow - TTL_MS / 2), secret, inWindow)).toBe(
-      'u1',
-    );
+  it('rejects pre-separation legacy tokens — the dual-verify window is gone (#296)', () => {
+    const now = Date.now();
+    // Unexpired on its own terms — rejected because only the subkey verifies.
+    expect(verifyUnsubscribeToken(legacyToken('u1', now - 1000), secret, now)).toBeNull();
   });
 
-  it('rejects a legacy token once the dual-verify window has closed', () => {
-    const afterWindow = LEGACY_VERIFY_UNTIL + 1000;
-    // Unexpired on its own terms — rejected purely because the window closed.
-    const token = legacyToken('u1', afterWindow - 1000);
-    expect(verifyUnsubscribeToken(token, secret, afterWindow)).toBeNull();
-  });
-
-  it('verifies freshly minted tokens via the subkey, independent of the window', () => {
-    const afterWindow = LEGACY_VERIFY_UNTIL + 24 * 60 * 60 * 1000;
-    const token = signUnsubscribeToken('u1', secret, afterWindow);
-    expect(verifyUnsubscribeToken(token, secret, afterWindow + 1000)).toBe('u1');
+  it('verifies freshly minted tokens via the subkey', () => {
+    const now = Date.now();
+    const token = signUnsubscribeToken('u1', secret, now);
+    expect(verifyUnsubscribeToken(token, secret, now + 1000)).toBe('u1');
   });
 });

apps/api/src/notifications/unsubscribe-token.ts

@@ -13,26 +13,17 @@ import { deriveTokenKey } from '@dorfteich/shared/token-crypto';
 
 const TTL_SECONDS = 90 * 24 * 60 * 60;
 
-/**
- * Dual-verify window (#188, ADR 0020): before the key separation, tokens
- * were HMACed with the root secret over a `digest-unsubscribe.` prefix.
- * Those links live in digest mails that are already sent and stay valid
- * for their full 90-day TTL, so verification accepts the legacy derivation
- * until every pre-separation token has expired. Tokens are only ever
- * SIGNED with the new subkey; the legacy path is verify-only and goes dead
- * automatically on the date below (last possible legacy expiry, rounded up).
- */
-export const LEGACY_VERIFY_UNTIL = Date.parse('2026-11-01T00:00:00Z');
-const LEGACY_PURPOSE = 'digest-unsubscribe';
+// The pre-#188 dual-verify window (root secret + `digest-unsubscribe.`
+// prefix) was removed EARLY by operator decision at the ADR 0020
+// acceptance (issue #296): links in mails sent before the key separation
+// no longer work — recipients use the in-app notification settings.
+// Verification is subkey-only; the regression test pins that the legacy
+// derivation can never verify again.
 
 function signature(body: string, rootSecret: string): Buffer {
   return createHmac('sha256', deriveTokenKey(rootSecret, 'unsubscribe')).update(body).digest();
 }
 
-function legacySignature(body: string, rootSecret: string): Buffer {
-  return createHmac('sha256', rootSecret).update(`${LEGACY_PURPOSE}.${body}`).digest();
-}
-
 export function signUnsubscribeToken(userId: string, rootSecret: string, now = Date.now()): string {
   const body = Buffer.from(
     JSON.stringify({ userId, exp: Math.floor(now / 1000) + TTL_SECONDS }),
@@ -59,10 +50,7 @@ export function verifyUnsubscribeToken(
   } catch {
     return null;
   }
-  const current = matches(provided, signature(body, rootSecret));
-  const legacy =
-    !current && now < LEGACY_VERIFY_UNTIL && matches(provided, legacySignature(body, rootSecret));
-  if (!current && !legacy) return null;
+  if (!matches(provided, signature(body, rootSecret))) return null;
   try {
     const payload = JSON.parse(Buffer.from(body, 'base64url').toString('utf8')) as {
       userId?: string;

apps/api/src/pages/pages.module.ts

@@ -1,6 +1,5 @@
 import { Module } from '@nestjs/common';
 
-import { PondsModule } from '../ponds/ponds.module';
 import { WatchesModule } from '../watches/watches.module';
 import { SearchModule } from '../search/search.module';
 
@@ -10,7 +9,7 @@ import { PluginApiController } from './plugin-api.controller';
 import { TasksService } from './tasks.service';
 
 @Module({
-  imports: [PondsModule, SearchModule, WatchesModule],
+  imports: [SearchModule, WatchesModule],
   controllers: [PagesController, PluginApiController],
   providers: [PagesService, TasksService],
   exports: [PagesService, TasksService],

apps/api/src/pages/plugin-api.e2e.db.test.ts

@@ -5,7 +5,7 @@ import { afterAll, beforeAll, describe, expect, it } from 'vitest';
 
 import { PondsService } from '../ponds/ponds.service';
 import { createTestApp, sessionCookieOf } from '../testing/test-app';
-import { createTestPrisma, hasTestDb, uniqueSuffix } from '../testing/test-db';
+import { createTestPrisma, deletePondsWhere, hasTestDb, uniqueSuffix } from '../testing/test-db';
 import { UsersService } from '../users/users.service';
 
 /**
@@ -23,6 +23,7 @@ describe.skipIf(!hasTestDb)('plugin API (e2e, issue #74)', () => {
   const userIds: Record<string, string> = {};
   const cookies: Record<string, string> = {};
   let pondId: string;
+  let startPageId: string;
   let openPageId: string;
   let secretPageId: string;
 
@@ -71,6 +72,10 @@ describe.skipIf(!hasTestDb)('plugin API (e2e, issue #74)', () => {
       .send({ name: `PlugApi Pond ${suffix}` })
       .expect(201);
     pondId = pond.body.id;
+    // Every pond created through the api starts with a page (issue #302);
+    // a "full reader sees everything" assertion has to include it rather
+    // than pretend the pond began empty.
+    startPageId = pond.body.settings.startPageId as string;
 
     const open = await api()
       .post(`/api/v1/ponds/${pondId}/pages`)
@@ -128,10 +133,10 @@ describe.skipIf(!hasTestDb)('plugin API (e2e, issue #74)', () => {
     await prisma.pageContentCache.deleteMany({ where: { page: { pondId } } });
     await prisma.pageUpdate.deleteMany({ where: { page: { pondId } } });
     await prisma.page.deleteMany({ where: { pondId } });
-    await prisma.pond.deleteMany({ where: { id: pondId } });
+    await deletePondsWhere(prisma, { id: pondId });
     const ids = Object.values(userIds);
     await prisma.roleGrant.deleteMany({ where: { pond: { ownerId: { in: ids } } } });
-    await prisma.pond.deleteMany({ where: { ownerId: { in: ids } } });
+    await deletePondsWhere(prisma, { ownerId: { in: ids } });
     await prisma.quotaOverride.deleteMany({ where: { subjectId: { in: ids } } });
     await prisma.user.deleteMany({ where: { id: { in: ids } } });
     await prisma.$disconnect();
@@ -144,7 +149,7 @@ describe.skipIf(!hasTestDb)('plugin API (e2e, issue #74)', () => {
       .set('Cookie', cookies.owner!)
       .expect(200);
     expect(res.body.map((p: { id: string }) => p.id).sort()).toEqual(
-      [openPageId, secretPageId].sort(),
+      [startPageId, openPageId, secretPageId].sort(),
     );
     expect(res.body[0]).toMatchObject({ title: expect.any(String), slug: expect.any(String) });
     // Label *names* travel with each summary (issue #77, page-index filter).

apps/api/src/pages/sort-key.test.ts

@@ -26,48 +26,56 @@ describe('sort-key helpers (issue #45)', () => {
    * pattern — repeatedly drop the last page between the first two — must never
    * collide and never overflow the key length, because the caller rebalances
    * when {@link nextKeyOrRebalance} returns null.
+   *
+   * Under parallel CI load the 10.000 iterations have repeatedly exceeded the
+   * default 5 s per-test timeout (runs 685, 699 — same code passed on rerun),
+   * so this test carries its own budget.
    */
-  it('10.000 adversarial reorders never collide or overflow (rebalance verified)', () => {
-    // Start with five pages in a fixed order.
-    let order = evenlySpacedKeys(5).map((key, i) => ({ id: `p${i}`, key }));
-    let rebalances = 0;
+  it(
+    '10.000 adversarial reorders never collide or overflow (rebalance verified)',
+    { timeout: 30_000 },
+    () => {
+      // Start with five pages in a fixed order.
+      let order = evenlySpacedKeys(5).map((key, i) => ({ id: `p${i}`, key }));
+      let rebalances = 0;
 
-    const rebalance = (): void => {
-      const keys = evenlySpacedKeys(order.length);
-      order = order.map((page, i) => ({ ...page, key: keys[i]! }));
-      rebalances += 1;
-    };
+      const rebalance = (): void => {
+        const keys = evenlySpacedKeys(order.length);
+        order = order.map((page, i) => ({ ...page, key: keys[i]! }));
+        rebalances += 1;
+      };
 
-    for (let i = 0; i < 10_000; i += 1) {
-      // Move the last page to sit between the first and second — the tightest
-      // possible gap, which is what grows key length fastest.
-      const moved = order[order.length - 1]!;
-      const rest = order.slice(0, -1);
-      const afterKey = rest[0]!.key;
-      const beforeKey = rest[1]!.key;
+      for (let i = 0; i < 10_000; i += 1) {
+        // Move the last page to sit between the first and second — the tightest
+        // possible gap, which is what grows key length fastest.
+        const moved = order[order.length - 1]!;
+        const rest = order.slice(0, -1);
+        const afterKey = rest[0]!.key;
+        const beforeKey = rest[1]!.key;
 
-      const key = nextKeyOrRebalance(afterKey, beforeKey);
-      if (key === null) {
-        // Rebalance keeps the CURRENT order, then retry the move once.
-        rebalance();
-        const k2 = nextKeyOrRebalance(order[0]!.key, order[1]!.key);
-        expect(k2).not.toBeNull();
-        order = [order[0]!, { ...moved, key: k2! }, ...order.slice(1)];
-      } else {
-        order = [rest[0]!, { ...moved, key }, ...rest.slice(1)];
+        const key = nextKeyOrRebalance(afterKey, beforeKey);
+        if (key === null) {
+          // Rebalance keeps the CURRENT order, then retry the move once.
+          rebalance();
+          const k2 = nextKeyOrRebalance(order[0]!.key, order[1]!.key);
+          expect(k2).not.toBeNull();
+          order = [order[0]!, { ...moved, key: k2! }, ...order.slice(1)];
+        } else {
+          order = [rest[0]!, { ...moved, key }, ...rest.slice(1)];
+        }
+
+        // Invariants after every move: keys unique, bounded, and consistent with
+        // the intended array order.
+        const keys = order.map((p) => p.key);
+        expect(new Set(keys).size).toBe(keys.length);
+        expect(Math.max(...keys.map((k) => k.length))).toBeLessThanOrEqual(MAX_SORT_KEY_LENGTH);
+        for (let j = 1; j < keys.length; j += 1) {
+          expect(keys[j - 1]! < keys[j]!).toBe(true);
+        }
       }
 
-      // Invariants after every move: keys unique, bounded, and consistent with
-      // the intended array order.
-      const keys = order.map((p) => p.key);
-      expect(new Set(keys).size).toBe(keys.length);
-      expect(Math.max(...keys.map((k) => k.length))).toBeLessThanOrEqual(MAX_SORT_KEY_LENGTH);
-      for (let j = 1; j < keys.length; j += 1) {
-        expect(keys[j - 1]! < keys[j]!).toBe(true);
-      }
-    }
-
-    // The adversarial pattern must have forced at least one rebalance.
-    expect(rebalances).toBeGreaterThan(0);
-  });
+      // The adversarial pattern must have forced at least one rebalance.
+      expect(rebalances).toBeGreaterThan(0);
+    },
+  );
 });

apps/api/src/permissions/permissions.e2e.db.test.ts

@@ -6,7 +6,7 @@ import { afterAll, beforeAll, describe, expect, it } from 'vitest';
 
 import { PondsService } from '../ponds/ponds.service';
 import { createTestApp, sessionCookieOf } from '../testing/test-app';
-import { createTestPrisma, hasTestDb, uniqueSuffix } from '../testing/test-db';
+import { createTestPrisma, deletePondsWhere, hasTestDb, uniqueSuffix } from '../testing/test-db';
 import { UsersService } from '../users/users.service';
 
 /**
@@ -120,11 +120,11 @@ describe.skipIf(!hasTestDb)('permission enforcement (e2e, issue #52)', () => {
     await prisma.pageContentCache.deleteMany({ where: { page: { pondId } } });
     await prisma.pageUpdate.deleteMany({ where: { page: { pondId } } });
     await prisma.page.deleteMany({ where: { pondId } });
-    await prisma.pond.deleteMany({ where: { id: pondId } });
+    await deletePondsWhere(prisma, { id: pondId });
     // Personal ponds (and their grants) before their users.
     const ids = Object.values(userIds);
     await prisma.roleGrant.deleteMany({ where: { pond: { ownerId: { in: ids } } } });
-    await prisma.pond.deleteMany({ where: { ownerId: { in: ids } } });
+    await deletePondsWhere(prisma, { ownerId: { in: ids } });
     await prisma.quotaOverride.deleteMany({ where: { subjectId: { in: ids } } });
     await prisma.user.deleteMany({ where: { id: { in: ids } } });
     await prisma.$disconnect();

apps/api/src/plugins/plugin-admin.controller.ts

@@ -2,6 +2,7 @@ import {
   BadRequestException,
   Body,
   ConflictException,
+  ForbiddenException,
   Controller,
   Delete,
   Get,
@@ -40,6 +41,10 @@ function toHttpException(error: PluginPackageError): HttpException {
     case 'plugin_version_not_higher':
     case 'plugin_not_optional':
       return new ConflictException(body);
+    // Hash pinning (#232): the upload is well-formed, the policy says no.
+    case 'plugin_not_pinned':
+    case 'plugin_hash_mismatch':
+      return new ForbiddenException(body);
     case 'plugin_too_large':
       return new PayloadTooLargeException(body);
     default:

apps/api/src/plugins/plugin-assets.controller.ts

@@ -96,7 +96,9 @@ export class PluginAssetsController {
     @Param('version') version: string,
     @Res({ passthrough: true }) response: Response,
   ): Promise<string> {
-    const plugin = await this.plugins.get(id);
+    // getServable enforces the hash-pinning allowlist (#232): a blocked
+    // plugin 404s here exactly like a missing one, and is audited.
+    const plugin = await this.plugins.getServable(id);
     if (!plugin || plugin.version !== version) throw new NotFoundException();
 
     // Asset base is built from the configured public origin, not the request
@@ -122,8 +124,9 @@ export class PluginAssetsController {
     @Res({ passthrough: true }) response: Response,
   ): Promise<StreamableFile> {
     // Only serve assets for an installed, current version — a removed plugin or
-    // a stale version pointer must not leak files.
-    const plugin = await this.plugins.get(id);
+    // a stale version pointer must not leak files. getServable additionally
+    // enforces the hash-pinning allowlist (#232).
+    const plugin = await this.plugins.getServable(id);
     if (!plugin || plugin.version !== version) throw new NotFoundException();
 
     const rest = (request.params as Record<string, unknown>).rest;

apps/api/src/plugins/plugin-pinning.e2e.db.test.ts

@@ -0,0 +1,172 @@
+import { createHash } from 'node:crypto';
+
+import { INestApplication } from '@nestjs/common';
+import { PrismaClient } from '@prisma/client';
+import { zipSync } from 'fflate';
+import request from 'supertest';
+import { afterAll, beforeAll, describe, expect, it } from 'vitest';
+
+import { InstanceSettingsService } from '../settings/instance-settings.service';
+import { createTestApp, sessionCookieOf } from '../testing/test-app';
+import { createTestPrisma, hasTestDb, uniqueSuffix } from '../testing/test-db';
+import { UsersService } from '../users/users.service';
+
+const enc = (text: string) => new TextEncoder().encode(text);
+
+function manifest(overrides: Record<string, unknown> = {}): Record<string, unknown> {
+  return {
+    id: 'pin-me',
+    name: 'Pin Me',
+    version: '1.0.0',
+    apiVersion: '1',
+    kind: 'code',
+    extensionPoints: [{ type: 'pageTool', id: 'pin', title: { de: 'Pin', en: 'Pin' } }],
+    permissions: [],
+    license: 'MIT',
+    ...overrides,
+  };
+}
+
+function pluginZip(m: Record<string, unknown>, bundle = 'export default {}'): Buffer {
+  return Buffer.from(
+    zipSync({ 'manifest.json': enc(JSON.stringify(m)), 'plugin.js': enc(bundle) }),
+  );
+}
+
+const sha256 = (buffer: Buffer) => createHash('sha256').update(buffer).digest('hex');
+
+/**
+ * Hash-pinning allowlist (issue #232, ADR 0025): with a non-empty
+ * `plugins.allowlist`, only pinned ids with the exact bundle hash install
+ * and load; tampered or unpinned bundles fail closed with a stable code,
+ * every rejection is audited, and a version bump requires an explicit
+ * re-pin. Empty allowlist = unchanged behaviour (backward compatible).
+ */
+describe.skipIf(!hasTestDb)('plugin hash pinning (e2e, issue #232)', () => {
+  let app: INestApplication;
+  let prisma: PrismaClient;
+  let settings: InstanceSettingsService;
+  const suffix = uniqueSuffix();
+  const password = 'gepinnt ist gepinnt 1';
+  let adminCookie: string;
+  let adminId: string;
+
+  const api = () => request(app.getHttpServer());
+  const zipV1 = pluginZip(manifest());
+  const zipV1Tampered = pluginZip(manifest(), 'export default { evil: true }');
+  const zipV2 = pluginZip(manifest({ version: '1.1.0' }));
+
+  async function setAllowlist(entries: { id: string; sha256: string }[]): Promise<void> {
+    await settings.set('plugins.allowlist', entries, adminId);
+  }
+
+  beforeAll(async () => {
+    prisma = createTestPrisma();
+    await prisma.pondPlugin.deleteMany({});
+    await prisma.plugin.deleteMany({});
+    await prisma.instanceSetting.deleteMany({ where: { key: 'plugins.allowlist' } });
+    app = await createTestApp();
+    settings = app.get(InstanceSettingsService);
+    const users = app.get(UsersService);
+    const adminUser = await users.createUser({
+      username: `pin-admin-${suffix}`,
+      email: `pin-admin-${suffix}@example.org`,
+      displayName: 'Pin Admin',
+      password,
+      locale: 'en',
+    });
+    await users.markEmailVerified(adminUser.id);
+    await prisma.user.update({ where: { id: adminUser.id }, data: { isSiteAdmin: true } });
+    adminId = adminUser.id;
+    adminCookie = sessionCookieOf(
+      await api()
+        .post('/api/v1/auth/login')
+        .send({ usernameOrEmail: `pin-admin-${suffix}`, password })
+        .expect(200),
+    );
+  });
+
+  afterAll(async () => {
+    await prisma.instanceSetting.deleteMany({ where: { key: 'plugins.allowlist' } });
+    await prisma.pondPlugin.deleteMany({});
+    await prisma.plugin.deleteMany({});
+    await prisma.auditEntry.deleteMany({ where: { targetId: { in: ['pin-me', 'stranger'] } } });
+    await prisma.user.deleteMany({ where: { username: { contains: suffix } } });
+    await prisma.$disconnect();
+    await app.close();
+  });
+
+  it('empty allowlist: installs record the hash, nothing is enforced', async () => {
+    const res = await api()
+      .post('/api/v1/admin/plugins')
+      .set('Cookie', adminCookie)
+      .attach('file', zipV1, 'pin-me.zip')
+      .expect(201);
+    expect(res.body.pinning).toBe('not_enforced');
+    expect(res.body.bundleSha256).toBe(sha256(zipV1));
+    await api().get(`/api/v1/plugins/pin-me/1.0.0/frame`).expect(200);
+  });
+
+  it('pinned hash: plugin stays loadable and reports pinned', async () => {
+    await setAllowlist([{ id: 'pin-me', sha256: sha256(zipV1) }]);
+    const list = await api().get('/api/v1/admin/plugins').set('Cookie', adminCookie).expect(200);
+    expect(list.body[0].pinning).toBe('pinned');
+    await api().get(`/api/v1/plugins/pin-me/1.0.0/frame`).expect(200);
+  });
+
+  it('unpinned plugin: install rejected with the stable code and audited', async () => {
+    const res = await api()
+      .post('/api/v1/admin/plugins')
+      .set('Cookie', adminCookie)
+      .attach('file', pluginZip(manifest({ id: 'stranger', name: 'Stranger' })), 'stranger.zip')
+      .expect(403);
+    expect(res.body.code).toBe('plugin_not_pinned');
+    const audit = await prisma.auditEntry.findFirst({
+      where: { action: 'plugin.rejected', targetId: 'stranger' },
+    });
+    expect(audit).not.toBeNull();
+  });
+
+  it('tampered bundle: same id + pin, different bytes — install rejected', async () => {
+    // A tampered re-delivery of the pinned version arrives as an update
+    // attempt; the hash gate must fire before any version comparison.
+    const res = await api()
+      .post('/api/v1/admin/plugins')
+      .set('Cookie', adminCookie)
+      .attach('file', zipV1Tampered, 'pin-me.zip')
+      .expect(403);
+    expect(res.body.code).toBe('plugin_hash_mismatch');
+  });
+
+  it('pin changed away from the installed hash: plugin no longer loads, audited', async () => {
+    await setAllowlist([{ id: 'pin-me', sha256: sha256(zipV1Tampered) }]);
+    const list = await api().get('/api/v1/admin/plugins').set('Cookie', adminCookie).expect(200);
+    // The admin still SEES the plugin, with the deviation named…
+    expect(list.body[0].pinning).toBe('mismatch');
+    // …but nothing serves it: frame 404s and the rejection is audited.
+    await api().get(`/api/v1/plugins/pin-me/1.0.0/frame`).expect(404);
+    const audit = await prisma.auditEntry.findFirst({
+      where: { action: 'plugin.rejected', targetId: 'pin-me' },
+    });
+    expect(audit).not.toBeNull();
+  });
+
+  it('version bump requires an explicit re-pin', async () => {
+    await setAllowlist([{ id: 'pin-me', sha256: sha256(zipV1) }]);
+    const rejected = await api()
+      .post('/api/v1/admin/plugins')
+      .set('Cookie', adminCookie)
+      .attach('file', zipV2, 'pin-me-1.1.zip')
+      .expect(403);
+    expect(rejected.body.code).toBe('plugin_hash_mismatch');
+
+    await setAllowlist([{ id: 'pin-me', sha256: sha256(zipV2) }]);
+    const res = await api()
+      .post('/api/v1/admin/plugins')
+      .set('Cookie', adminCookie)
+      .attach('file', zipV2, 'pin-me-1.1.zip')
+      .expect(201);
+    expect(res.body.pinning).toBe('pinned');
+    await api().get(`/api/v1/plugins/pin-me/1.1.0/frame`).expect(200);
+  });
+});

apps/api/src/plugins/plugins.e2e.db.test.ts

@@ -9,7 +9,7 @@ import { afterAll, beforeAll, describe, expect, it } from 'vitest';
 
 import { AuthTokensService } from '../auth/auth-tokens.service';
 import { createTestApp, sessionCookieOf } from '../testing/test-app';
-import { createTestPrisma, hasTestDb, uniqueSuffix } from '../testing/test-db';
+import { createTestPrisma, deletePondsWhere, hasTestDb, uniqueSuffix } from '../testing/test-db';
 import { UsersService } from '../users/users.service';
 
 import { PluginStorageService } from './plugin-storage.service';
@@ -456,7 +456,7 @@ describe.skipIf(!hasTestDb)('plugins kill switch (e2e, issue #200)', () => {
     await prisma.plugin.deleteMany({ where: { id: pluginId } });
     const where = { pond: { owner: { username: { contains: suffix } } } };
     await prisma.roleGrant.deleteMany({ where });
-    await prisma.pond.deleteMany({ where: { owner: { username: { contains: suffix } } } });
+    await deletePondsWhere(prisma, { owner: { username: { contains: suffix } } });
     await prisma.user.deleteMany({ where: { username: { contains: suffix } } });
     await app.close();
   });

apps/api/src/plugins/plugins.service.ts

@@ -1,3 +1,5 @@
+import { createHash } from 'node:crypto';
+
 import { Injectable } from '@nestjs/common';
 import { Plugin, PluginInstanceMode as DbPluginMode, Prisma, User } from '@prisma/client';
 import { PinoLogger } from 'nestjs-pino';
@@ -12,6 +14,7 @@ import type {
 import { ClockService } from '../common/clock.service';
 import { AuditService } from '../audit/audit.service';
 import { PrismaService } from '../prisma/prisma.service';
+import { InstanceSettingsService } from '../settings/instance-settings.service';
 
 import { PluginPackageService } from './plugin-package.service';
 import { PluginStorageService } from './plugin-storage.service';
@@ -44,6 +47,7 @@ export class PluginsService {
     private readonly storage: PluginStorageService,
     private readonly clock: ClockService,
     private readonly audit: AuditService,
+    private readonly settings: InstanceSettingsService,
     private readonly logger: PinoLogger,
   ) {
     this.logger.setContext(PluginsService.name);
@@ -58,6 +62,32 @@ export class PluginsService {
   /** `actor` is absent for dropzone installs (watcher, no session). */
   async install(zip: Buffer, actor?: User): Promise<PluginView> {
     const { manifest, files } = this.packages.parse(zip);
+    const bundleHash = createHash('sha256').update(zip).digest('hex');
+
+    // Hash pinning (#232, ADR 0025): while the allowlist is non-empty,
+    // only listed ids with the exact pinned bundle hash may install.
+    // Fail closed with a distinct code per cause; every rejection is
+    // audited so a tampering attempt leaves a trace.
+    const allowlist = await this.settings.get('plugins.allowlist');
+    if (allowlist.length > 0) {
+      const pin = allowlist.find((entry) => entry.id === manifest.id);
+      if (!pin || pin.sha256 !== bundleHash) {
+        const reason = pin ? 'hash_mismatch' : 'not_pinned';
+        await this.audit.record({
+          action: 'plugin.rejected',
+          actorId: actor?.id,
+          targetType: 'plugin',
+          targetId: manifest.id,
+          details: { surface: 'install', reason, version: manifest.version, bundleHash },
+        });
+        throw new PluginPackageError(
+          pin ? 'plugin_hash_mismatch' : 'plugin_not_pinned',
+          pin
+            ? `Bundle hash ${bundleHash} does not match the pinned hash for ${manifest.id}`
+            : `Plugin ${manifest.id} is not on the allowlist`,
+        );
+      }
+    }
 
     const existing = await this.prisma.plugin.findUnique({ where: { id: manifest.id } });
     const isActiveUpdate = existing !== null && existing.removedAt === null;
@@ -81,6 +111,7 @@ export class PluginsService {
         apiVersion: manifest.apiVersion,
         kind: manifest.kind,
         manifest: manifest as unknown as Prisma.InputJsonValue,
+        bundleHash,
       },
       update: {
         name: manifest.name,
@@ -88,6 +119,7 @@ export class PluginsService {
         apiVersion: manifest.apiVersion,
         kind: manifest.kind,
         manifest: manifest as unknown as Prisma.InputJsonValue,
+        bundleHash,
         // Reinstalling a previously removed plugin clears the tombstone.
         removedAt: null,
       },
@@ -105,7 +137,7 @@ export class PluginsService {
       targetId: manifest.id,
       details: { version: manifest.version, update: isActiveUpdate },
     });
-    return this.toView(record);
+    return this.toView(record, await this.settings.get('plugins.allowlist'));
   }
 
   /**
@@ -131,7 +163,7 @@ export class PluginsService {
       targetId: id,
       details: { mode },
     });
-    return this.toView(updated);
+    return this.toView(updated, await this.settings.get('plugins.allowlist'));
   }
 
   /**
@@ -182,9 +214,18 @@ export class PluginsService {
       this.prisma.pondPlugin.findMany({ where: { pondId } }),
     ]);
     const enabled = new Map(activations.map((a) => [a.pluginId, a.enabled]));
-    return plugins
-      .filter((p) => p.mode === 'REQUIRED' || (p.mode === 'OPTIONAL' && enabled.get(p.id) === true))
-      .map((p) => this.toView(p));
+    const allowlist = await this.settings.get('plugins.allowlist');
+    return (
+      plugins
+        .filter(
+          (p) => p.mode === 'REQUIRED' || (p.mode === 'OPTIONAL' && enabled.get(p.id) === true),
+        )
+        // Hash pinning (#232): a plugin outside the allowlist, or with a
+        // deviating bundle hash, does not load — it simply never appears in
+        // the pond's mount list. Existing blocks render their fallback.
+        .filter((p) => this.loadable(this.verdict(p, allowlist)))
+        .map((p) => this.toView(p, allowlist))
+    );
   }
 
   /**
@@ -219,7 +260,11 @@ export class PluginsService {
       this.prisma.pondPlugin.findMany({ where: { pondId } }),
     ]);
     const enabled = new Map(activations.map((a) => [a.pluginId, a.enabled]));
-    return plugins.map((p) => ({ plugin: this.toView(p), enabled: enabled.get(p.id) === true }));
+    const allowlist = await this.settings.get('plugins.allowlist');
+    return plugins.map((p) => ({
+      plugin: this.toView(p, allowlist),
+      enabled: enabled.get(p.id) === true,
+    }));
   }
 
   /**
@@ -287,19 +332,66 @@ export class PluginsService {
       where: { removedAt: null },
       orderBy: { name: 'asc' },
     });
-    return plugins.map((plugin) => this.toView(plugin));
+    const allowlist = await this.settings.get('plugins.allowlist');
+    return plugins.map((plugin) => this.toView(plugin, allowlist));
   }
 
   /** One installed plugin, or `null` if absent/removed. */
   async get(id: string): Promise<PluginView | null> {
     const plugin = await this.prisma.plugin.findUnique({ where: { id } });
     if (!plugin || plugin.removedAt !== null) return null;
-    return this.toView(plugin);
+    return this.toView(plugin, await this.settings.get('plugins.allowlist'));
   }
 
-  private toView(plugin: Plugin): PluginView {
+  /**
+   * Pinning verdict against `plugins.allowlist` (#232). The observed hash
+   * is the one recorded at install: post-install tampering with unpacked
+   * files on disk is platform integrity (ADR 0019), not this check's
+   * scope — the pin answers "is this the reviewed bundle".
+   */
+  private verdict(
+    plugin: Plugin,
+    allowlist: { id: string; sha256: string }[],
+  ): PluginView['pinning'] {
+    if (allowlist.length === 0) return 'not_enforced';
+    const pin = allowlist.find((entry) => entry.id === plugin.id);
+    if (!pin) return 'unpinned';
+    return plugin.bundleHash === pin.sha256 ? 'pinned' : 'mismatch';
+  }
+
+  private loadable(verdict: PluginView['pinning']): boolean {
+    return verdict === 'not_enforced' || verdict === 'pinned';
+  }
+
+  /**
+   * The load gate for code-serving surfaces (frame + assets, #232): an
+   * installed plugin outside the allowlist, or with a deviating bundle
+   * hash, does not load — 404 like a missing plugin, and the rejection is
+   * audited (unlike the silent list filtering, an asset request proves
+   * something actively referenced the blocked plugin).
+   */
+  async getServable(id: string): Promise<PluginView | null> {
+    const plugin = await this.prisma.plugin.findUnique({ where: { id } });
+    if (!plugin || plugin.removedAt !== null) return null;
+    const allowlist = await this.settings.get('plugins.allowlist');
+    const verdict = this.verdict(plugin, allowlist);
+    if (!this.loadable(verdict)) {
+      await this.audit.record({
+        action: 'plugin.rejected',
+        targetType: 'plugin',
+        targetId: id,
+        details: { surface: 'load', reason: verdict, version: plugin.version },
+      });
+      return null;
+    }
+    return this.toView(plugin, allowlist);
+  }
+
+  private toView(plugin: Plugin, allowlist: { id: string; sha256: string }[]): PluginView {
     const manifest = plugin.manifest as unknown as PluginManifest;
     return {
+      bundleSha256: plugin.bundleHash,
+      pinning: this.verdict(plugin, allowlist),
       id: plugin.id,
       name: plugin.name,
       version: plugin.version,

apps/api/src/ponds/ponds.e2e.db.test.ts

@@ -5,7 +5,7 @@ import { afterAll, beforeAll, describe, expect, it, vi } from 'vitest';
 
 import { AuthTokensService } from '../auth/auth-tokens.service';
 import { createTestApp, sessionCookieOf } from '../testing/test-app';
-import { createTestPrisma, hasTestDb, uniqueSuffix } from '../testing/test-db';
+import { createTestPrisma, deletePondsWhere, hasTestDb, uniqueSuffix } from '../testing/test-db';
 import { UsersService } from '../users/users.service';
 import { PondAccessNotifier } from './pond-access-notifier.service';
 
@@ -81,7 +81,7 @@ describe.skipIf(!hasTestDb)('ponds (e2e, issue #21)', () => {
     await prisma.quotaOverride.deleteMany({
       where: { subjectId: { in: users.map((u) => u.id) } },
     });
-    await prisma.pond.deleteMany({ where: { owner: { username: { contains: suffix } } } });
+    await deletePondsWhere(prisma, { owner: { username: { contains: suffix } } });
     await prisma.user.deleteMany({ where: { username: { contains: suffix } } });
     await prisma.$disconnect();
     await app.close();
@@ -106,6 +106,107 @@ describe.skipIf(!hasTestDb)('ponds (e2e, issue #21)', () => {
     expect(res.body.filter((p: { type: string }) => p.type === 'personal')).toHaveLength(1);
   });
 
+  it('gives a new shared pond a start page and points settings at it (issue #302)', async () => {
+    const created = await api()
+      .post('/api/v1/ponds')
+      .set('Cookie', ownerCookie)
+      .send({ name: `Startseitenteich ${suffix}` })
+      .expect(201);
+
+    const pages = await api()
+      .get(`/api/v1/ponds/${created.body.id}/pages`)
+      .set('Cookie', ownerCookie)
+      .expect(200);
+    expect(pages.body).toHaveLength(1);
+
+    // The title follows the creator's stored locale — this owner is 'de'.
+    expect(pages.body[0].title).toBe('Startseite');
+
+    const pond = await api()
+      .get(`/api/v1/ponds/${created.body.slug}`)
+      .set('Cookie', ownerCookie)
+      .expect(200);
+    expect(pond.body.settings.startPageId).toBe(pages.body[0].id);
+  });
+
+  it("titles the start page in the creator's locale (issue #302)", async () => {
+    // The owner is 'de' and got "Startseite" above; an 'en' account must get
+    // the English title. Without both halves the test would pass on a
+    // hardcoded string just as happily.
+    const users = app.get(UsersService);
+    const tokens = app.get(AuthTokensService);
+    const username = `ellie-${suffix}`;
+    const user = await users.createUser({
+      username,
+      email: `${username}@example.org`,
+      displayName: `Ellie English ${suffix}`,
+      password,
+      locale: 'en',
+    });
+    const token = await tokens.issue(user.id, 'EMAIL_VERIFICATION', 600);
+    await api().post('/api/v1/auth/verify-email').send({ token }).expect(204);
+
+    const pond = await prisma.pond.findFirstOrThrow({
+      where: { ownerId: user.id, type: 'PERSONAL' },
+    });
+    const pages = await prisma.page.findMany({ where: { pondId: pond.id } });
+    expect(pages.map((page) => page.title)).toEqual(['Home']);
+  });
+
+  it('gives the personal pond a start page too (issue #302)', async () => {
+    const res = await api().get('/api/v1/ponds').set('Cookie', ownerCookie).expect(200);
+    const personal = res.body.find((p: { type: string }) => p.type === 'personal');
+    const pages = await api()
+      .get(`/api/v1/ponds/${personal.id}/pages`)
+      .set('Cookie', ownerCookie)
+      .expect(200);
+    expect(pages.body).toHaveLength(1);
+    expect(personal.settings.startPageId).toBe(pages.body[0].id);
+  });
+
+  it('changes the start page without losing other settings (issue #302)', async () => {
+    const created = await api()
+      .post('/api/v1/ponds')
+      .set('Cookie', ownerCookie)
+      .send({ name: `Wechselteich ${suffix}` })
+      .expect(201);
+    await api()
+      .patch(`/api/v1/ponds/${created.body.id}`)
+      .set('Cookie', ownerCookie)
+      .send({ commentPolicy: 'editors' })
+      .expect(200);
+
+    const second = await api()
+      .post(`/api/v1/ponds/${created.body.id}/pages`)
+      .set('Cookie', ownerCookie)
+      .send({ title: `Zweite ${suffix}` })
+      .expect(201);
+    const updated = await api()
+      .patch(`/api/v1/ponds/${created.body.id}`)
+      .set('Cookie', ownerCookie)
+      .send({ startPageId: second.body.id })
+      .expect(200);
+
+    expect(updated.body.settings.startPageId).toBe(second.body.id);
+    // The neighbouring key must survive the merge — settings hold only
+    // deviations, so an assigning write would silently reset it.
+    expect(updated.body.settings.commentPolicy).toBe('editors');
+  });
+
+  it('clears the start page back to the sort-order default (issue #302)', async () => {
+    const created = await api()
+      .post('/api/v1/ponds')
+      .set('Cookie', ownerCookie)
+      .send({ name: `Leerteich ${suffix}` })
+      .expect(201);
+    const cleared = await api()
+      .patch(`/api/v1/ponds/${created.body.id}`)
+      .set('Cookie', ownerCookie)
+      .send({ startPageId: null })
+      .expect(200);
+    expect(cleared.body.settings.startPageId).toBeNull();
+  });
+
   it('creates shared ponds with deterministic slug suffixes', async () => {
     const name = `Gartenteich ${suffix}`;
     const first = await api()

apps/api/src/ponds/ponds.module.ts

@@ -1,5 +1,6 @@
 import { Module } from '@nestjs/common';
 
+import { PagesModule } from '../pages/pages.module';
 import { QuotasModule } from '../quotas/quotas.module';
 import { SearchModule } from '../search/search.module';
 
@@ -8,7 +9,7 @@ import { PondsController } from './ponds.controller';
 import { PondsService } from './ponds.service';
 
 @Module({
-  imports: [QuotasModule, SearchModule],
+  imports: [PagesModule, QuotasModule, SearchModule],
   controllers: [PondsController],
   providers: [PondsService, PondAccessNotifier],
   exports: [PondsService, PondAccessNotifier],

apps/api/src/ponds/ponds.service.ts

@@ -9,6 +9,8 @@ import {
 import { Pond, Prisma, User } from '@prisma/client';
 import { PinoLogger } from 'nestjs-pino';
 
+import { apiI18n } from '../i18n/api-i18n';
+import { PagesService } from '../pages/pages.service';
 import { PermissionService } from '../permissions/permission.service';
 import { PrismaService } from '../prisma/prisma.service';
 import { QuotaService } from '../quotas/quota.service';
@@ -23,11 +25,52 @@ export class PondsService {
     private readonly quotas: QuotaService,
     private readonly accessNotifier: PondAccessNotifier,
     private readonly search: SearchProvider,
+    private readonly pages: PagesService,
     private readonly logger: PinoLogger,
   ) {
     this.logger.setContext(PondsService.name);
   }
 
+  /**
+   * Every new pond opens on a start page instead of the empty-pond hint
+   * (issue #302). Deliberately AFTER the creating transaction commits: the
+   * owner's POND_ADMIN grant is written inside it and the permission layer
+   * caches per pond, so creating the page in the same transaction would ask
+   * about rights the grant has not yet published.
+   *
+   * Goes through PagesService so the page carries every invariant a page
+   * needs — unique slug, appended sort key, derived content cache, search
+   * indexing, and an `emptyPageState()` the collab server can bind to. A
+   * hand-rolled insert here would produce a page the editor cannot open.
+   *
+   * Failure is logged, not fatal: a pond without a start page simply falls
+   * back to the historical behaviour, which is a working state. Losing the
+   * whole pond over its first page would not be.
+   */
+  private async createStartPage(owner: User, pondId: string): Promise<void> {
+    try {
+      const title = apiI18n.t('ponds:startPage.title', {
+        lng: owner.locale === 'de' ? 'de' : 'en',
+      });
+      const page = await this.pages.create(owner, pondId, { title });
+      const pond = await this.prisma.pond.findUniqueOrThrow({
+        where: { id: pondId },
+        select: { settings: true },
+      });
+      // Merge rather than assign: stored settings hold only deviations from
+      // the defaults, and overwriting the object would drop them.
+      await this.prisma.pond.update({
+        where: { id: pondId },
+        data: { settings: { ...(pond.settings as object), startPageId: page.id } },
+      });
+    } catch (error) {
+      this.logger.error(
+        { pondId, err: error instanceof Error ? error.message : String(error) },
+        'start page for new pond could not be created',
+      );
+    }
+  }
+
   viewOf(pond: Pond): PondView {
     return {
       id: pond.id,
@@ -105,7 +148,12 @@ export class PondsService {
       return created;
     });
     this.logger.info({ pondId: pond.id, ownerId: owner.id }, 'audit: pond created');
-    return this.viewOf(pond);
+    await this.createStartPage(owner, pond.id);
+    // Re-read: the row captured in the transaction predates the start page,
+    // so returning it would hand the caller `startPageId: null` for a pond
+    // that has one.
+    const withStartPage = await this.prisma.pond.findUniqueOrThrow({ where: { id: pond.id } });
+    return this.viewOf(withStartPage);
   }
 
   /**
@@ -128,6 +176,7 @@ export class PondsService {
       return created;
     });
     this.logger.info({ pondId: pond.id, ownerId: user.id }, 'audit: personal pond created');
+    await this.createStartPage(user, pond.id);
   }
 
   async listVisible(user: User): Promise<PondView[]> {
@@ -157,7 +206,8 @@ export class PondsService {
       input.commentPolicy !== undefined ||
       input.apiEnabled !== undefined ||
       input.mcpEnabled !== undefined ||
-      input.theme !== undefined;
+      input.theme !== undefined ||
+      input.startPageId !== undefined;
     const settings = !settingsChanged
       ? undefined
       : {
@@ -169,6 +219,7 @@ export class PondsService {
           ...(input.apiEnabled !== undefined ? { apiEnabled: input.apiEnabled } : {}),
           ...(input.mcpEnabled !== undefined ? { mcpEnabled: input.mcpEnabled } : {}),
           ...(input.theme !== undefined ? { theme: input.theme } : {}),
+          ...(input.startPageId !== undefined ? { startPageId: input.startPageId } : {}),
         };
     const updated = await this.prisma.pond.update({
       where: { id },

apps/api/src/settings/instance-settings.service.ts

@@ -1,10 +1,16 @@
-import { BadRequestException, Injectable } from '@nestjs/common';
-import { DEFAULT_ATTACHMENT_EXTENSIONS } from '@dorfteich/shared';
+import { BadRequestException, ForbiddenException, Injectable } from '@nestjs/common';
+import {
+  DEFAULT_ATTACHMENT_EXTENSIONS,
+  VS_NFD_PROFILE,
+  brandingAssetSchema,
+  isVsNfdCompliant,
+} from '@dorfteich/shared';
 import { Prisma } from '@prisma/client';
 import { PinoLogger } from 'nestjs-pino';
 import { z } from 'zod';
 
 import { AuditService } from '../audit/audit.service';
+import { AppConfig } from '../config/app-config.service';
 import { PrismaService } from '../prisma/prisma.service';
 
 /**
@@ -15,8 +21,21 @@ import { PrismaService } from '../prisma/prisma.service';
  */
 export const INSTANCE_SETTINGS = {
   'auth.registrationMode': z.enum(['open', 'closed']).default('open'),
+  // Peer invitations (issue #332): max OPEN (pending, unexpired)
+  // invitations per user; 0 turns inviting off entirely.
+  'invitations.maxOpenPerUser': z.number().int().min(0).default(5),
   'instance.name': z.string().trim().min(1).max(60).default('Dorfteich'),
   'instance.defaultLocale': z.enum(['de', 'en']).default('en'),
+  // Branding assets (issue #306). Metadata only — the PNG bytes live under
+  // BRANDING_DIR and travel in the restore set; `hash` goes into the serving
+  // URL so a replaced asset is picked up without cache trouble. Null = not
+  // uploaded: the instance name renders as text, the favicon falls back to
+  // the shipped default. `logoDark` is optional by design — without it the
+  // LIGHT logo is used in both themes, because showing the operator's own
+  // asset unchanged beats substituting one they did not choose (#307).
+  'instance.logo': brandingAssetSchema.nullable().default(null),
+  'instance.logoDark': brandingAssetSchema.nullable().default(null),
+  'instance.favicon': brandingAssetSchema.nullable().default(null),
   // Instance-default quotas (ADR 0011); per-user/per-pond overrides live
   // in quota_overrides and win over these (QuotaService, issue #22).
   'quota.editorsPerPond': z.number().int().min(0).default(5),
@@ -139,6 +158,26 @@ export const INSTANCE_SETTINGS = {
   // (an image fallback degrades to neutral text: its bytes live on the
   // disabled asset surface).
   'plugins.enabled': z.boolean().default(true),
+  // Plugin allowlist with SHA-256 hash pinning (issue #232, ADR 0025).
+  // Empty (the default) = pinning is NOT enforced — plugins load as
+  // before, which keeps existing instances working. Non-empty = only the
+  // listed plugin ids load, and only while the installed bundle's
+  // observed hash equals the pinned one; installs of unlisted or
+  // mismatching bundles are rejected, loads fail closed (assets/frame
+  // 404, audited `plugin.rejected`). A version bump changes the bundle
+  // hash, so it requires an explicit re-pin — the intended friction.
+  'plugins.allowlist': z
+    .array(
+      z.object({
+        id: z.string().min(1),
+        sha256: z
+          .string()
+          .trim()
+          .toLowerCase()
+          .regex(/^[a-f0-9]{64}$/),
+      }),
+    )
+    .default([]),
   // Atom feed master switch (issue #191). Default ON: feeds predate the
   // switch, so existing instances and their subscribed readers keep
   // working; the VS-NfD reference configuration (#227) turns it off.
@@ -201,6 +240,7 @@ export class InstanceSettingsService {
     private readonly prisma: PrismaService,
     private readonly audit: AuditService,
     private readonly logger: PinoLogger,
+    private readonly config: AppConfig,
   ) {
     this.logger.setContext(InstanceSettingsService.name);
   }
@@ -237,6 +277,22 @@ export class InstanceSettingsService {
         details: { [key]: parsed.error.issues.map((i) => i.message) },
       });
     }
+    // Mode `enforced` (#246, ADR 0027): a write that would set a
+    // catalog-violating value is rejected at the ONE write path every
+    // caller uses — hiding alone (#245) is UI cosmetics a scripted client
+    // bypasses. Existing violating values are reported (startup log,
+    // admin card), never auto-changed: the operator resolves them
+    // consciously, and writes that DECREASE compliance are what this
+    // blocks. 403, not 400: the request is well-formed, the policy says no.
+    if (this.config.env.VS_NFD_MODE === 'enforced') {
+      const entry = VS_NFD_PROFILE.find((e) => e.scope === 'instance' && e.key === key);
+      if (entry && !isVsNfdCompliant(entry, parsed.data)) {
+        throw new ForbiddenException({
+          code: 'vs_nfd_profile_violation',
+          details: { [key]: ['vs_nfd_profile_violation'] },
+        });
+      }
+    }
     // Nullable settings (setup.completedAt) store JSON null explicitly —
     // Prisma requires the sentinel for that.
     const stored = parsed.data === null ? Prisma.JsonNull : parsed.data;

apps/api/src/settings/vs-nfd-enforced.e2e.db.test.ts

@@ -0,0 +1,143 @@
+import { INestApplication } from '@nestjs/common';
+import { type VsNfdProfileView } from '@dorfteich/shared';
+import { PrismaClient } from '@prisma/client';
+import request from 'supertest';
+import { afterAll, beforeAll, describe, expect, it } from 'vitest';
+
+import { createTestApp, sessionCookieOf } from '../testing/test-app';
+import { createTestPrisma, hasTestDb, uniqueSuffix } from '../testing/test-db';
+import { UsersService } from '../users/users.service';
+
+/**
+ * Mode `enforced` (issue #246, ADR 0027): the api rejects settings writes
+ * that would set a catalog-violating value — with a stable error code —
+ * while existing violations are reported and never auto-changed. The mode
+ * is env-fixed per boot, so each mode gets its own app (sequential
+ * describes; pattern vs-nfd-profile.e2e.db.test.ts).
+ */
+async function makeAdmin(
+  app: INestApplication,
+  prisma: PrismaClient,
+  suffix: string,
+): Promise<string> {
+  const users = app.get(UsersService);
+  const username = `enf-admin-${suffix}`;
+  const user = await users.createUser({
+    username,
+    email: `${username}@example.org`,
+    displayName: 'Enf Admin',
+    password: 'erzwungen ist erzwungen 1',
+    locale: 'en',
+  });
+  await users.markEmailVerified(user.id);
+  await prisma.user.update({ where: { id: user.id }, data: { isSiteAdmin: true } });
+  return sessionCookieOf(
+    await request(app.getHttpServer())
+      .post('/api/v1/auth/login')
+      .send({ usernameOrEmail: username, password: 'erzwungen ist erzwungen 1' })
+      .expect(200),
+  );
+}
+
+describe.skipIf(!hasTestDb)('VS-NfD mode enforced (e2e, issue #246)', () => {
+  let app: INestApplication;
+  let prisma: PrismaClient;
+  let cookie: string;
+  const suffix = uniqueSuffix();
+
+  beforeAll(async () => {
+    process.env.VS_NFD_MODE = 'enforced';
+    prisma = createTestPrisma();
+    await prisma.rateLimit.deleteMany({});
+    // A violation that exists BEFORE the enforced boot: reported, never
+    // auto-changed (feeds.enabled default is true = violating anyway, but
+    // pin it as an explicit stored row).
+    await prisma.instanceSetting.upsert({
+      where: { key: 'feeds.enabled' },
+      create: { key: 'feeds.enabled', value: true },
+      update: { value: true },
+    });
+    app = await createTestApp();
+    cookie = await makeAdmin(app, prisma, suffix);
+  });
+
+  afterAll(async () => {
+    delete process.env.VS_NFD_MODE;
+    await prisma.instanceSetting.deleteMany({
+      where: { key: { in: ['feeds.enabled', 'auth.registrationMode', 'upload.svgPolicy'] } },
+    });
+    await prisma.user.deleteMany({ where: { username: { contains: suffix } } });
+    await prisma.$disconnect();
+    await app.close();
+  });
+
+  it('rejects a violating write with the stable error code', async () => {
+    const res = await request(app.getHttpServer())
+      .patch('/api/v1/admin/settings')
+      .set('Cookie', cookie)
+      .send({ 'upload.svgPolicy': 'sanitize' })
+      .expect(403);
+    expect(res.body.code).toBe('vs_nfd_profile_violation');
+    // Nothing was stored — the read still returns the schema default.
+    const settings = await request(app.getHttpServer())
+      .get('/api/v1/admin/settings')
+      .set('Cookie', cookie)
+      .expect(200);
+    expect(settings.body['upload.svgPolicy']).toBe('sanitize');
+  });
+
+  it('accepts compliant writes', async () => {
+    await request(app.getHttpServer())
+      .patch('/api/v1/admin/settings')
+      .set('Cookie', cookie)
+      .send({ 'auth.registrationMode': 'closed', 'upload.svgPolicy': 'reject' })
+      .expect(200);
+  });
+
+  it('reports the pre-existing violation and never auto-changes it', async () => {
+    const profile = (
+      await request(app.getHttpServer())
+        .get('/api/v1/admin/system/vs-nfd-profile')
+        .set('Cookie', cookie)
+        .expect(200)
+    ).body as VsNfdProfileView;
+    expect(profile.mode).toBe('enforced');
+    expect(profile.entries.find((e) => e.key === 'feeds.enabled')!.compliant).toBe(false);
+    const settings = await request(app.getHttpServer())
+      .get('/api/v1/admin/settings')
+      .set('Cookie', cookie)
+      .expect(200);
+    expect(settings.body['feeds.enabled']).toBe(true);
+  });
+});
+
+describe.skipIf(!hasTestDb)('the same write passes outside enforced (issue #246)', () => {
+  let app: INestApplication;
+  let prisma: PrismaClient;
+  let cookie: string;
+  const suffix = uniqueSuffix();
+
+  beforeAll(async () => {
+    process.env.VS_NFD_MODE = 'hidden';
+    prisma = createTestPrisma();
+    await prisma.rateLimit.deleteMany({});
+    app = await createTestApp();
+    cookie = await makeAdmin(app, prisma, suffix);
+  });
+
+  afterAll(async () => {
+    delete process.env.VS_NFD_MODE;
+    await prisma.instanceSetting.deleteMany({ where: { key: 'upload.svgPolicy' } });
+    await prisma.user.deleteMany({ where: { username: { contains: suffix } } });
+    await prisma.$disconnect();
+    await app.close();
+  });
+
+  it('mode hidden: the violating write is NOT rejected (UI-level only)', async () => {
+    await request(app.getHttpServer())
+      .patch('/api/v1/admin/settings')
+      .set('Cookie', cookie)
+      .send({ 'upload.svgPolicy': 'sanitize' })
+      .expect(200);
+  });
+});

apps/api/src/settings/vs-nfd-profile.e2e.db.test.ts

@@ -93,6 +93,14 @@ describe.skipIf(!hasTestDb)('VS-NfD profile endpoint (e2e, issue #243)', () => {
     expect(view.violations).toBeGreaterThan(0);
   });
 
+  it('mode marked: a violating write is NOT rejected (issue #246 contrast)', async () => {
+    await api()
+      .patch('/api/v1/admin/settings')
+      .set('Cookie', cookies.admin!)
+      .send({ 'upload.svgPolicy': 'sanitize' })
+      .expect(200);
+  });
+
   it('verdict follows a settings change', async () => {
     const settings = app.get(InstanceSettingsService);
     const before = (

apps/api/src/settings/vs-nfd-profile.service.ts

@@ -1,4 +1,5 @@
-import { Injectable } from '@nestjs/common';
+import { Injectable, type OnModuleInit } from '@nestjs/common';
+import { PinoLogger } from 'nestjs-pino';
 import {
   VS_NFD_PROFILE,
   describeCompliance,
@@ -20,11 +21,33 @@ import { InstanceSettingsService, type InstanceSettings } from './instance-setti
  * (#244–#246) build on this evaluation; here it is exposure only.
  */
 @Injectable()
-export class VsNfdProfileService {
+export class VsNfdProfileService implements OnModuleInit {
   constructor(
     private readonly settings: InstanceSettingsService,
     private readonly config: AppConfig,
-  ) {}
+    private readonly logger: PinoLogger,
+  ) {
+    this.logger.setContext(VsNfdProfileService.name);
+  }
+
+  /** Startup report (#246): existing violations are stated once, never
+   * auto-changed — the operator resolves them consciously. Must not throw
+   * on a database-less boot (healthz suites boot without a db). */
+  async onModuleInit(): Promise<void> {
+    if (this.config.env.VS_NFD_MODE === 'off') return;
+    try {
+      const view = await this.evaluate();
+      this.logger.info(
+        {
+          mode: view.mode,
+          violations: view.entries.filter((e) => !e.compliant).map((e) => e.key),
+        },
+        'VS-NfD profile verdict at startup',
+      );
+    } catch {
+      // Stated at the next successful evaluation instead.
+    }
+  }
 
   private valueOf(entry: VsNfdProfileEntry, settings: InstanceSettings): unknown {
     return entry.scope === 'instance'

apps/api/src/setup/setup.e2e.db.test.ts

@@ -317,6 +317,42 @@ describe.skipIf(!hasTestDb)('first-run setup wizard (fresh database, issue #80)'
       expect(locked.body.code).toBe('setup_locked');
     });
   });
+
+  describe('env pre-seeding with invalid values (issue #325)', () => {
+    const dbName = `dorfteich_preseed_bad_${suffix}`;
+    let app: INestApplication;
+    const badEnv = {
+      SETUP_ADMIN_USERNAME: `preseed-bad-${suffix}`,
+      SETUP_ADMIN_EMAIL: `preseed-bad-${suffix}@example.org`,
+      SETUP_ADMIN_PASSWORD: 'short',
+    } as const;
+
+    beforeAll(async () => {
+      const url = await createFreshDatabase(dbName);
+      process.env.TEST_DATABASE_URL = url;
+      process.env.SECRETS_FILE = join(
+        mkdtempSync(join(tmpdir(), 'dorfteich-preseed-bad-')),
+        'secrets.env',
+      );
+      Object.assign(process.env, badEnv);
+      app = await createTestApp();
+    }, 60_000);
+
+    afterAll(async () => {
+      for (const key of Object.keys(badEnv)) delete process.env[key];
+      await app.close();
+      await dropDatabase(dbName);
+    });
+
+    it('fails the boot naming the SETUP_* variable, not a raw ZodError', async () => {
+      await expect(app.get(SetupService).preseedFromEnv()).rejects.toThrow(
+        /SETUP_ADMIN_PASSWORD must be at least 10 characters/,
+      );
+      // Fail-fast left nothing half-seeded: the wizard is still pending.
+      const status = await request(app.getHttpServer()).get('/api/v1/setup').expect(200);
+      expect(status.body.status).toBe('required');
+    });
+  });
 });
 
 interface FakeSmtpServer {

apps/api/src/setup/setup.service.ts

@@ -15,6 +15,7 @@ import {
 } from '@dorfteich/shared';
 import { User } from '@prisma/client';
 import { PinoLogger } from 'nestjs-pino';
+import { ZodError } from 'zod';
 
 import { SessionsService } from '../auth/sessions.service';
 import { AppConfig } from '../config/app-config.service';
@@ -70,14 +71,23 @@ export class SetupService implements OnModuleInit {
     if (!(await this.state.isPending())) return;
 
     // Fails the boot loudly on invalid values — a half-seeded instance
-    // would be much harder to diagnose than a startup error.
-    const input = setupAdminInputSchema.parse({
+    // would be much harder to diagnose than a startup error. Translated
+    // into operator terms first: the raw ZodError names schema fields and
+    // i18n keys, not the SETUP_* variable to fix (issue #325).
+    const parsed = setupAdminInputSchema.safeParse({
       username: env.SETUP_ADMIN_USERNAME,
       email: env.SETUP_ADMIN_EMAIL,
       password: env.SETUP_ADMIN_PASSWORD,
       displayName: env.SETUP_ADMIN_DISPLAY_NAME ?? env.SETUP_ADMIN_USERNAME,
       locale: env.SETUP_DEFAULT_LOCALE,
     });
+    if (!parsed.success) {
+      throw new Error(
+        `Pre-seeding failed: ${describePreseedIssues(parsed.error)}. ` +
+          'Fix .env and recreate the api container.',
+      );
+    }
+    const input = parsed.data;
     const admin = await this.createAdmin(input);
     if (env.SETUP_INSTANCE_NAME) {
       await this.settings.set('instance.name', env.SETUP_INSTANCE_NAME, admin.id);
@@ -223,3 +233,27 @@ export class SetupService implements OnModuleInit {
     return (await this.prisma.user.count({ where: { isSiteAdmin: true } })) > 0;
   }
 }
+
+/** The env variable behind each schema field of the pre-seeded admin. */
+const PRESEED_FIELD_TO_ENV: Record<string, string> = {
+  username: 'SETUP_ADMIN_USERNAME',
+  email: 'SETUP_ADMIN_EMAIL',
+  password: 'SETUP_ADMIN_PASSWORD',
+  displayName: 'SETUP_ADMIN_DISPLAY_NAME',
+  locale: 'SETUP_DEFAULT_LOCALE',
+};
+
+function describePreseedIssues(error: ZodError): string {
+  return error.issues
+    .map((issue) => {
+      const variable = PRESEED_FIELD_TO_ENV[String(issue.path[0])] ?? String(issue.path[0]);
+      if (issue.code === 'too_small' && issue.type === 'string') {
+        return `${variable} must be at least ${issue.minimum} characters`;
+      }
+      if (issue.code === 'invalid_string' && issue.validation === 'email') {
+        return `${variable} is not a valid e-mail address`;
+      }
+      return `${variable} is invalid (${issue.message})`;
+    })
+    .join('; ');
+}

apps/api/src/testing/test-db.ts

@@ -1,4 +1,4 @@
-import { PrismaClient } from '@prisma/client';
+import { Prisma, PrismaClient } from '@prisma/client';
 
 /** True when database-backed tests can run (see vitest.global-setup.ts). */
 export const hasTestDb = Boolean(process.env.TEST_DATABASE_URL);
@@ -40,3 +40,27 @@ export async function grantOwnerAdmin(
     },
   });
 }
+
+/**
+ * Deletes the ponds matching `where`, their pages first.
+ *
+ * `Page.pond` deliberately carries no `onDelete: Cascade` — a real purge
+ * (TrashService) removes a pond's contents explicitly and audits it, and a
+ * silent database cascade would hide that. Since issue #302 every pond
+ * created through the api starts with a page, so teardowns that went
+ * straight for `pond.deleteMany` now hit the foreign key.
+ *
+ * Page-owned rows (updates, comments, links, …) do cascade from the page.
+ */
+export async function deletePondsWhere(
+  prisma: PrismaClient,
+  where: Prisma.PondWhereInput,
+): Promise<void> {
+  const pondIds = (await prisma.pond.findMany({ where, select: { id: true } })).map(
+    (pond) => pond.id,
+  );
+  if (pondIds.length === 0) return;
+  await prisma.attachment.deleteMany({ where: { pondId: { in: pondIds } } });
+  await prisma.page.deleteMany({ where: { pondId: { in: pondIds } } });
+  await prisma.pond.deleteMany({ where: { id: { in: pondIds } } });
+}

apps/api/src/trash/pond-purge.e2e.db.test.ts

@@ -231,7 +231,10 @@ describe.skipIf(!hasTestDb)('pond purge (e2e, issue #193)', () => {
       where: { action: 'pond.purged', targetId: pondId },
     });
     expect(audit).not.toBeNull();
-    expect(audit!.details).toMatchObject({ trigger: 'manual', pages: 2, attachments: 1 });
+    // Two pages created here plus the pond's own start page (issue #302) —
+    // the audit records what was actually removed, so the count moves with
+    // the pond's real contents rather than with what the test typed out.
+    expect(audit!.details).toMatchObject({ trigger: 'manual', pages: 3, attachments: 1 });
   });
 
   it('purges due ponds on the retention path with an audit event', async () => {

apps/api/src/trash/trash.module.ts

@@ -1,5 +1,6 @@
 import { Module, OnModuleInit } from '@nestjs/common';
 
+import { BrandingModule } from '../branding/branding.module';
 import { CommonModule } from '../common/common.module';
 import { FilesModule } from '../files/files.module';
 import { PagesModule } from '../pages/pages.module';
@@ -18,6 +19,7 @@ const TRASH_PURGE_CADENCE_SECONDS = 24 * 60 * 60;
 
 @Module({
   imports: [
+    BrandingModule,
     CommonModule,
     PondsModule,
     QuotasModule,

apps/api/src/trash/trash.service.ts

@@ -4,6 +4,7 @@ import { User } from '@prisma/client';
 import { PinoLogger } from 'nestjs-pino';
 
 import { AuditService } from '../audit/audit.service';
+import { BrandingService } from '../branding/branding.service';
 import { ClockService } from '../common/clock.service';
 import { SearchProvider } from '../search/search.provider';
 import { PagesService } from '../pages/pages.service';
@@ -32,6 +33,7 @@ export class TrashService {
     private readonly settings: InstanceSettingsService,
     private readonly quotas: QuotaService,
     private readonly storage: FileStorageService,
+    private readonly branding: BrandingService,
     private readonly clock: ClockService,
     private readonly watches: WatchesService,
     private readonly audit: AuditService,
@@ -183,6 +185,9 @@ export class TrashService {
     for (const attachment of attachments) {
       await this.storage.delete(pondId, attachment.id);
     }
+    // The pond's branding files (issue #307). The purge standard is absolute:
+    // after it, nothing referencing the pond survives — rows OR files.
+    await this.branding.removePondAssets(pondId);
     const pageIds = (
       await this.prisma.page.findMany({ where: { pondId }, select: { id: true } })
     ).map((page) => page.id);

apps/backup/Dockerfile

@@ -20,6 +20,7 @@ ENV NODE_ENV=production APP_VERSION=${APP_VERSION} \
     # Baked-in volume paths (self-sufficient without compose env, like the
     # api image's PLUGINS_DIR — issue #71's lesson).
     BACKUPS_DIR=/backups UPLOADS_DIR=/data/uploads PLUGINS_DIR=/data/plugins \
+    CUSTOM_FONTS_DIR=/data/fonts BRANDING_DIR=/data/branding \
     SECRETS_FILE=/data/secrets/secrets.env
 # pg_dump/pg_restore matching the stack's postgres:17 server, GNU tar for the
 # volume archives, tzdata so BACKUP_TIME honors a configured TZ, and

apps/backup/src/data-dirs.test.ts

@@ -0,0 +1,30 @@
+import { backupEnvSchema } from '@dorfteich/shared';
+import { describe, expect, it } from 'vitest';
+
+import { dataDirs } from './data-dirs.js';
+
+/**
+ * The fence against the failure #303 hit and #306 could repeat: a new data
+ * directory gets its env entry but not its line here, and the nightly archive
+ * skips it WORDLESSLY (`createArchive` tolerates missing directories on
+ * purpose). Nobody notices until a restore comes up short.
+ *
+ * Every `*_DIR` the backup sidecar knows must therefore travel in the archive.
+ * `BACKUPS_DIR` is the exception by definition — it is where the archive is
+ * written, not something archived into it.
+ */
+const NOT_DATA = new Set(['BACKUPS_DIR']);
+
+describe('data directories (issues #303/#306)', () => {
+  it('archives every *_DIR the backup env declares', () => {
+    const env = backupEnvSchema.parse({ DATABASE_URL: 'postgresql://x/y' });
+    const values = env as unknown as Record<string, unknown>;
+    const declared = Object.keys(env).filter((key) => key.endsWith('_DIR') && !NOT_DATA.has(key));
+    const archived = dataDirs(env);
+
+    expect(declared.length).toBeGreaterThan(0);
+    for (const key of declared) {
+      expect(archived, `${key} is missing from dataDirs()`).toContain(values[key]);
+    }
+  });
+});

apps/backup/src/data-dirs.ts

@@ -0,0 +1,18 @@
+import type { BackupEnv } from '@dorfteich/shared';
+
+/**
+ * The data directories that travel in a restore set's archive (ADR 0015).
+ *
+ * ONE list, used by the nightly archive AND by the restore — they must not
+ * drift, or a backup would carry something the restore never puts back.
+ * Adding a new persistent data directory is a one-line change here plus the
+ * env entry and the compose mount.
+ *
+ * All of them must share a parent directory: `archiveBase` derives the tar
+ * root from that and throws otherwise.
+ */
+export function dataDirs(
+  env: Pick<BackupEnv, 'UPLOADS_DIR' | 'PLUGINS_DIR' | 'CUSTOM_FONTS_DIR' | 'BRANDING_DIR'>,
+): string[] {
+  return [env.UPLOADS_DIR, env.PLUGINS_DIR, env.CUSTOM_FONTS_DIR, env.BRANDING_DIR];
+}

apps/backup/src/index.ts

@@ -6,6 +6,7 @@ import { pino } from 'pino';
 
 import { createArchive } from './archive.js';
 import { createCommandListener } from './commands.js';
+import { dataDirs } from './data-dirs.js';
 import { loadBackupEnv } from './config.js';
 import { sendFailureMail } from './mail.js';
 import { mirrorSets, resolveMirrorConfig } from './mirror.js';
@@ -50,7 +51,7 @@ async function buildRunnerDeps(trigger: 'scheduled' | 'manual'): Promise<RunnerD
     retentionDays: settings.localRetentionDays ?? env.BACKUP_RETENTION_DAYS,
     now: () => new Date(),
     dump: (outFile) => pgDump(env.DATABASE_URL, outFile),
-    archive: (outFile) => createArchive(outFile, [env.UPLOADS_DIR, env.PLUGINS_DIR]),
+    archive: (outFile) => createArchive(outFile, dataDirs(env)),
     onFailure: async (run) => {
       const sent = await sendFailureMail(env, run);
       if (!sent)

apps/backup/src/perform-restore.ts

@@ -5,18 +5,27 @@ import type { BackupEnv } from '@dorfteich/shared';
 
 import { extractArchive } from './archive.js';
 import { archiveFileName, dumpFileName } from './backup-set.js';
+import { dataDirs } from './data-dirs.js';
 import { pgRestore } from './pg.js';
 import type { RemoteLogger } from './remote.js';
 
 /**
  * Restores one local set into the live database and data volumes:
  * `pg_restore --clean --if-exists` of the dump, then the volume archive
- * back over the uploads/plugins mounts. Shared by the operator CLI
+ * back over the data mounts (see data-dirs.ts). Shared by the operator CLI
  * (restore.js via restore.sh) and the in-app restore orchestrator (#103) —
  * one restore path, exercised by drills and the app alike.
  */
 export async function performRestore(
-  env: Pick<BackupEnv, 'BACKUPS_DIR' | 'DATABASE_URL' | 'UPLOADS_DIR' | 'PLUGINS_DIR'>,
+  env: Pick<
+    BackupEnv,
+    | 'BACKUPS_DIR'
+    | 'DATABASE_URL'
+    | 'UPLOADS_DIR'
+    | 'PLUGINS_DIR'
+    | 'CUSTOM_FONTS_DIR'
+    | 'BRANDING_DIR'
+  >,
   backupId: string,
   log: RemoteLogger,
 ): Promise<void> {
@@ -29,6 +38,6 @@ export async function performRestore(
   }
   log.info({ backupId }, 'restoring database dump');
   await pgRestore(env.DATABASE_URL, dumpFile);
-  log.info({ backupId }, 'restoring uploads/plugins archive');
-  await extractArchive(archiveFile, [env.UPLOADS_DIR, env.PLUGINS_DIR]);
+  log.info({ backupId }, 'restoring the data-directory archive');
+  await extractArchive(archiveFile, dataDirs(env));
 }

apps/web/e2e/a11y.spec.ts

@@ -87,7 +87,27 @@ for (const scheme of SCHEMES) {
       await page.emulateMedia({ colorScheme: scheme });
       await page.goto('/settings');
       await page.waitForLoadState('networkidle');
+      // Einladungs-Abschnitt (issue #332) gerendert — sonst liefe der Scan
+      // auch grün, wenn die Sektion gar nicht erscheint.
+      await page.locator('.invitations').waitFor();
       await expectClean(page, `/settings (${scheme})`);
+
+      // Lizenzseite im selben Kontext (issue #304: sie trägt seit den
+      // eigenen Schriften zwei Tabellen samt Scroll-Regionen). Bewusst
+      // KEIN eigener Test — jeder zusätzliche Login im Pack bringt die
+      // CI zwei Packs später ans Rate-Limit (Lehre aus #301).
+      await page.goto('/fonts');
+      await page.waitForLoadState('networkidle');
+      await expectClean(page, `/fonts (${scheme})`);
+
+      // Teich-Einstellungen im selben Kontext (fixture-user besitzt den
+      // Fixture-Teich): dort sitzt seit issue #305 das Archiv-Angebot in der
+      // Löschzone. Wieder KEIN eigener Test — zusätzliche Logins kippen die
+      // CI zwei Packs später am Rate-Limit (Lehre aus #301).
+      await page.goto('/p/content-fixtures/settings');
+      await page.waitForLoadState('networkidle');
+      await page.locator('.pond-archive__download').waitFor();
+      await expectClean(page, `Teich-Einstellungen (${scheme})`);
       await context.close();
     });
 
@@ -99,8 +119,111 @@ for (const scheme of SCHEMES) {
       await page.waitForLoadState('networkidle');
       // Personenliste sichtbar, inkl. der Icon-Aktionen (issue #175).
       await page.locator('.user-manager__table .user-row').first().waitFor();
+      // Schriftverwaltung mitgeladen (issue #304) — ohne diese Zusicherung
+      // liefe der Scan auch dann grün, wenn der Abschnitt gar nicht rendert.
+      await page.locator('.custom-fonts__upload input[type="file"]').first().waitFor();
+      // Dasselbe für den Branding-Abschnitt (issue #306). Der Zuschnitt ist
+      // erst nach Dateiwahl sichtbar; geprüft wird die Dateiauswahl.
+      await page.locator('.branding .crop-field input[type="file"]').first().waitFor();
       await expectClean(page, `/admin (${scheme})`);
+      // Anlage-Dialog (issue #331) im selben Kontext öffnen und mitscannen —
+      // wieder KEIN eigener Test (Rate-Limit-Lehre aus #301).
+      await page.locator('.user-manager__create').click();
+      await page.locator('.create-user-dialog').waitFor();
+      await expectClean(page, `/admin Anlage-Dialog (${scheme})`);
       await context.close();
     });
   });
 }
+
+/**
+ * Reflow (WCAG 2.1 SC 1.4.10, issue #301): bei 320 px CSS-Breite — was 400 %
+ * Zoom auf 1280 px entspricht — darf die Seite nicht seitenweit horizontal
+ * scrollen. axe prüft das NICHT, das Kriterium ist nicht maschinell aus dem
+ * DOM ableitbar; deshalb ein eigener Zaun.
+ *
+ * Schlägt er an, nennt er die überstehenden Elemente. Ohne diese Diagnose
+ * weiß man nur DASS es überläuft und muss im Browser bisektieren.
+ */
+const NARROW = { width: 320, height: 800 };
+
+async function expectNoHorizontalScroll(page: Page, label: string): Promise<void> {
+  const report = await page.evaluate(() => {
+    const doc = document.documentElement;
+    const limit = doc.clientWidth;
+
+    const describe = (el: Element): string => {
+      const cls =
+        el.className && typeof el.className === 'string'
+          ? `.${el.className.trim().split(/\s+/).join('.')}`
+          : '';
+      return `${el.tagName.toLowerCase()}${cls}`;
+    };
+
+    // Every element whose own content is wider than its box. One of these is
+    // the source; the ones that scroll it away on purpose are marked.
+    const overflowing: string[] = [];
+    for (const el of Array.from(document.querySelectorAll('*'))) {
+      if (el.scrollWidth > el.clientWidth + 1 && el.clientWidth > 0) {
+        const overflowX = getComputedStyle(el).overflowX;
+        overflowing.push(
+          `${describe(el)} client=${el.clientWidth} scroll=${el.scrollWidth} overflow-x=${overflowX}`,
+        );
+      }
+    }
+
+    /** Content inside a scroll container may exceed the viewport — that is
+     *  the remedy. But only when the CONTAINER fits: a scroller that is
+     *  itself too wide still pushes the page. */
+    const insideFittingScroller = (el: Element): boolean => {
+      for (let node = el.parentElement; node && node !== doc; node = node.parentElement) {
+        const ox = getComputedStyle(node).overflowX;
+        if (ox === 'auto' || ox === 'scroll' || ox === 'hidden') {
+          return node.getBoundingClientRect().right <= limit + 1;
+        }
+      }
+      return false;
+    };
+
+    // Widest reach first, so a long tail of clipped children cannot bury the
+    // one box that actually pushes the page.
+    const past = Array.from(document.querySelectorAll('body *'))
+      .map((el) => ({ el, rect: el.getBoundingClientRect() }))
+      .filter(({ rect }) => rect.width > 0 && rect.right > limit + 1)
+      .sort((a, b) => b.rect.right - a.rect.right)
+      .map(
+        ({ el, rect }) =>
+          `${describe(el)} right=${Math.round(rect.right)} w=${Math.round(rect.width)}` +
+          `${insideFittingScroller(el) ? ' [in fitting scroller]' : ' <-- pushes page'}`,
+      );
+
+    return {
+      overflowBy: doc.scrollWidth - limit,
+      viewport: `html client=${limit} scroll=${doc.scrollWidth} | body client=${document.body.clientWidth} scroll=${document.body.scrollWidth} rect=${Math.round(document.body.getBoundingClientRect().width)}`,
+      overflowing: overflowing.slice(0, 15),
+      past: past.slice(0, 40),
+    };
+  });
+  const diagnosis = [
+    `${label}: horizontaler Überlauf bei 320 px`,
+    report.viewport,
+    `eigener Inhaltsüberlauf: ${JSON.stringify(report.overflowing, null, 1)}`,
+    `Boxen über dem Rand: ${JSON.stringify(report.past, null, 1)}`,
+  ].join('\n');
+  expect({ overflowBy: report.overflowBy }, diagnosis).toEqual({ overflowBy: 0 });
+}
+
+test.describe('reflow at 320px', () => {
+  test('user settings do not scroll horizontally at 320px', async ({ browser }) => {
+    const context = await contextForUser(browser, BASE, 'fixture-user');
+    const page = await context.newPage();
+    await page.setViewportSize(NARROW);
+    await page.goto('/settings');
+    await page.waitForLoadState('networkidle');
+    // Die Sitzungstabelle rendert asynchron und ist der breiteste Inhalt —
+    // ohne sie misst der Zaun eine halb aufgebaute Seite.
+    await page.locator('.table tbody tr').first().waitFor();
+    await expectNoHorizontalScroll(page, '/settings');
+    await context.close();
+  });
+});

apps/web/e2e/admin-settings.spec.ts

@@ -0,0 +1,55 @@
+import { expect, test } from '@playwright/test';
+
+import { contextForUser } from './helpers';
+
+const BASE_URL = process.env.E2E_BASE_URL ?? 'http://localhost:5173';
+
+/**
+ * The general admin settings card saves THROUGH THE FORM (issue #322).
+ *
+ * This must drive the UI, not the api: the bug it fences was invisible to
+ * every api-level test — react-hook-form nested the dotted field names on
+ * input, the strict PATCH schema rejected the body, and the form looked
+ * fine while never saving. Verified end to end: success message, the value
+ * survives a full reload, the api returns it, and the TopBar picks it up
+ * without a reload (branding query invalidation).
+ */
+test('instance name changed in the general settings form persists', async ({ browser }) => {
+  const admin = await contextForUser(browser, BASE_URL, 'fixture-admin');
+  const before = (
+    (await (await admin.request.get('/api/v1/admin/settings')).json()) as Record<string, unknown>
+  )['instance.name'] as string;
+  const newName = `Renamed ${Date.now()}`;
+
+  const nameLabel = /^(Instance name|Name der Instanz)$/;
+  const page = await admin.newPage();
+  try {
+    await page.goto('/admin');
+    const generalCard = page
+      .locator('section.settings-section')
+      .filter({ has: page.getByLabel(nameLabel) });
+    await page.getByLabel(nameLabel).fill(newName);
+    await generalCard.getByRole('button', { name: /^(Save|Speichern)$/ }).click();
+    // Scoped to the card: the page has several forms with status regions.
+    await expect(generalCard.getByRole('status')).toHaveText(/^(Saved\.|Gespeichert\.)$/);
+
+    // The TopBar and the document title show the new name without a reload —
+    // the save invalidates the branding query both read from (issue #323).
+    await expect(page.locator('.topbar__brand')).toHaveText(newName);
+    await expect(page).toHaveTitle(new RegExp(`${newName}$`));
+
+    // The proof the form really persisted: the value survives a reload and
+    // the api returns it.
+    await page.reload();
+    await expect(page.getByLabel(nameLabel)).toHaveValue(newName);
+    const stored = (
+      (await (await admin.request.get('/api/v1/admin/settings')).json()) as Record<string, unknown>
+    )['instance.name'];
+    expect(stored).toBe(newName);
+  } finally {
+    await admin.request.patch('/api/v1/admin/settings', {
+      data: { 'instance.name': before },
+    });
+    await admin.close();
+  }
+});

apps/web/e2e/admin-users.spec.ts

@@ -44,3 +44,43 @@ test('disabling a user in the admin UI blocks their login, enabling restores it'
     await admin.close();
   }
 });
+
+/**
+ * Direct account creation (issue #331): the dialog creates an active account
+ * — the new user logs in immediately, no verification hop. The account stays
+ * in the e2e database; the unique name keeps reruns independent.
+ */
+test('creating a user in the admin UI yields an account that can log in at once', async ({
+  browser,
+}) => {
+  const admin = await contextForUser(browser, BASE_URL, 'fixture-admin');
+  const username = `created-${Date.now()}`;
+  const password = 'ein sicheres anfangspasswort';
+
+  const page = await admin.newPage();
+  await page.goto('/admin');
+  await page.locator('.user-manager__create').click();
+
+  const dialog = page.getByRole('dialog');
+  await dialog.getByLabel(/username|benutzername/i).fill(username);
+  await dialog.getByLabel(/e-mail/i).fill(`${username}@example.org`);
+  await dialog.getByLabel(/display name|anzeigename/i).fill('Created via UI');
+  await dialog.getByLabel(/initial password|anfangspasswort/i).fill(password);
+  await dialog.getByRole('button', { name: /^create$|^anlegen$/i }).click();
+  await expect(dialog).toBeHidden();
+
+  // The list refetches; the fresh account is findable.
+  await page.locator('.user-manager__search').fill(username);
+  const row = page.locator(`.user-row[data-username="${username}"]`);
+  await expect(row).toBeVisible();
+  await expect(row.locator('.user-row__status')).toHaveText(/active|aktiv/i);
+  await admin.close();
+
+  // No verification mail hop: login works right away.
+  const ctx = await request.newContext({ baseURL: BASE_URL });
+  const res = await ctx.post('/api/v1/auth/login', {
+    data: { usernameOrEmail: username, password },
+  });
+  expect(res.status()).toBe(200);
+  await ctx.dispose();
+});

apps/web/e2e/editor.spec.ts

@@ -60,6 +60,155 @@ test('typing persists across reload and undo/redo work', async ({ browser }) =>
   await context.close();
 });
 
+test('gap cursor reaches positions before and after a lone table (issue #335)', async ({
+  browser,
+}) => {
+  const context = await contextForUser(browser, BASE_URL, 'fixture-user');
+  const { pondSlug, pageSlug } = await createPage(context, `E2E Gapcursor ${Date.now()}`);
+  const page = await context.newPage();
+
+  await page.goto(`/p/${pondSlug}/${pageSlug}`);
+  await page.getByRole('button', { name: /edit|bearbeiten/i }).click();
+  const status = page.locator('.editor-connection');
+  await expect(status).toHaveAttribute('data-status', 'connected', { timeout: 10000 });
+
+  const content = page.locator('.ProseMirror');
+  await content.click();
+  await page.getByRole('button', { name: /insert table|tabelle einfügen/i }).click();
+  await expect(content.locator('table')).toBeVisible();
+  // Inserting into the empty page replaces the placeholder paragraph — the
+  // table really is the only block, which is the situation of issue #335.
+  await expect(content.locator(':scope > p')).toHaveCount(0);
+  // Right after the insert the collab sync can still swallow a click's
+  // selection update; interact only against a settled editor (established
+  // pattern, see a11y.spec.ts). The typed markers below verify each click
+  // really placed the cursor where the locator points.
+  await page.waitForTimeout(500);
+
+  // Keyboard only: ArrowUp from the first cell lands on the gap cursor
+  // before the table; typing there materializes a paragraph.
+  await content.locator('th').first().click();
+  await page.keyboard.type('in');
+  await expect(content.locator('th').first()).toHaveText('in');
+  await page.keyboard.press('ArrowUp');
+  await expect(page.locator('.ProseMirror-gapcursor')).toHaveCount(1);
+  await page.keyboard.type('above');
+  await expect(content.locator(':scope > :first-child')).toHaveText('above');
+
+  // Same for the position after the table.
+  await content.locator('td').last().click();
+  await page.keyboard.type('z');
+  await expect(content.locator('td').last()).toHaveText('z');
+  await page.keyboard.press('ArrowDown');
+  await expect(page.locator('.ProseMirror-gapcursor')).toHaveCount(1);
+  await page.keyboard.type('below');
+  await expect(content.locator(':scope > :last-child')).toHaveText('below');
+
+  await context.close();
+});
+
+test('cells can be merged and split from the toolbar (issue #337)', async ({ browser }) => {
+  const context = await contextForUser(browser, BASE_URL, 'fixture-user');
+  const { pondSlug, pageSlug } = await createPage(context, `E2E MergeSplit ${Date.now()}`);
+  const page = await context.newPage();
+
+  await page.goto(`/p/${pondSlug}/${pageSlug}`);
+  await page.getByRole('button', { name: /edit|bearbeiten/i }).click();
+  const status = page.locator('.editor-connection');
+  await expect(status).toHaveAttribute('data-status', 'connected', { timeout: 10000 });
+
+  const content = page.locator('.ProseMirror');
+  await content.click();
+  await page.getByRole('button', { name: /insert table|tabelle einfügen/i }).click();
+  await expect(content.locator('table')).toBeVisible();
+
+  const mergeButton = page.getByRole('button', { name: /merge cells|zellen verbinden/i });
+  const splitButton = page.getByRole('button', { name: /split cell|zelle teilen/i });
+  await expect(mergeButton).toBeDisabled();
+  await expect(splitButton).toBeDisabled();
+  // Settle before clicking into cells — see the gap cursor test.
+  await page.waitForTimeout(500);
+
+  // Extending the selection across the cell border turns it into a cell
+  // selection (prosemirror-tables), which is what merge operates on.
+  // Shift+Click, not Shift+ArrowRight: a keypress fired in the same tick as
+  // the preceding click races the editor's post-click rendering and gets
+  // dropped — no human types that fast (works fine interactively).
+  await content.locator('td').first().click();
+  await content
+    .locator('td')
+    .nth(1)
+    .click({ modifiers: ['Shift'] });
+  await expect(content.locator('.selectedCell')).toHaveCount(2);
+  await expect(mergeButton).toBeEnabled();
+  await mergeButton.click();
+  await expect(content.locator('td[colspan="2"]')).toHaveCount(1);
+
+  // Splitting the merged cell restores the row's full cell count.
+  await content.locator('td[colspan="2"]').click();
+  await expect(splitButton).toBeEnabled();
+  await splitButton.click();
+  await expect(content.locator('td[colspan="2"]')).toHaveCount(0);
+  await expect(content.locator('tr').nth(1).locator('td')).toHaveCount(3);
+
+  await context.close();
+});
+
+test('Tab navigates table cells, extends the table, and never traps focus (issue #338)', async ({
+  browser,
+}) => {
+  const context = await contextForUser(browser, BASE_URL, 'fixture-user');
+  const { pondSlug, pageSlug } = await createPage(context, `E2E TableTab ${Date.now()}`);
+  const page = await context.newPage();
+
+  await page.goto(`/p/${pondSlug}/${pageSlug}`);
+  await page.getByRole('button', { name: /edit|bearbeiten/i }).click();
+  const status = page.locator('.editor-connection');
+  await expect(status).toHaveAttribute('data-status', 'connected', { timeout: 10000 });
+
+  const content = page.locator('.ProseMirror');
+  await content.click();
+  await page.getByRole('button', { name: /insert table|tabelle einfügen/i }).click();
+  const rows = content.locator('tr');
+  await expect(rows).toHaveCount(3);
+  // Settle before clicking into cells — see the gap cursor test.
+  await page.waitForTimeout(500);
+
+  // Tab moves to the next cell, Shift+Tab back. Typed markers prove where
+  // the cursor really is (the typing assertions also settle the editor
+  // between keypresses — see the merge test on click/key races).
+  await content.locator('th').first().click();
+  await page.keyboard.type('one');
+  await expect(content.locator('th').first()).toHaveText('one');
+  await page.keyboard.press('Tab');
+  await page.keyboard.type('two');
+  await expect(content.locator('th').nth(1)).toHaveText('two');
+  await page.keyboard.press('Shift+Tab');
+  await page.keyboard.type('back');
+  await expect(content.locator('th').first()).toContainText('back');
+
+  // Tab in the last cell appends a row and moves into it (Word behavior).
+  const lastCell = rows.nth(2).locator('td').nth(2);
+  await lastCell.click();
+  await page.keyboard.type('z');
+  await expect(lastCell).toHaveText('z');
+  await page.keyboard.press('Tab');
+  await expect(rows).toHaveCount(4);
+  await page.keyboard.type('new');
+  await expect(rows.nth(3).locator('td').first()).toHaveText('new');
+
+  // No keyboard trap (WCAG 2.1.2): Escape works from EVERY cell (the gap
+  // cursor is only reachable per arrow key from edge cells) and places the
+  // cursor after the table; once outside, Tab leaves the editor entirely.
+  // The mechanism is announced via the editor's aria-describedby hint.
+  await page.keyboard.press('Escape');
+  await expect(page.locator('.ProseMirror-gapcursor')).toHaveCount(1);
+  await page.keyboard.press('Tab');
+  await expect(content).not.toBeFocused();
+
+  await context.close();
+});
+
 test('edit mode hides the sidebar; leaving edit mode restores it', async ({ browser }) => {
   const context = await contextForUser(browser, BASE_URL, 'fixture-user');
   const { pondSlug, pageSlug } = await createPage(context, `E2E Sidebar ${Date.now()}`);

apps/web/e2e/import-vault.spec.ts

@@ -93,11 +93,19 @@ test('a pond admin imports an Obsidian vault through the settings dialog', async
   await expect(
     mountItem.locator('.sidebar__tree-children .sidebar__page', { hasText: 'Projekte' }),
   ).toBeVisible();
-  await expect(page.locator('.sidebar__page:text-is("Startseite")')).toBeVisible();
+  // Scoped to the mount: the pond has its own "Startseite" since issue #302,
+  // so an unscoped title match now finds two entries.
+  const importedHome = mountItem
+    .locator('.sidebar__tree-children .sidebar__page')
+    .filter({ hasText: /^Startseite$/ })
+    .first();
+  await expect(importedHome).toBeVisible();
 
   // A rewritten Obsidian link navigates to the right imported page, and the
-  // display text still reads like the original note name.
-  await page.goto(`/p/${pond.slug}/startseite`);
+  // display text still reads like the original note name. Reached through the
+  // sidebar rather than by slug — `/startseite` belongs to the pond's own
+  // start page, so the imported note landed on a suffixed slug.
+  await importedHome.click();
   await page.locator('.editor-content a.wikilink', { hasText: 'Projekt A' }).click();
   await expect(page).toHaveURL(new RegExp(`/p/${pond.slug}/projekt-a$`));
 

apps/web/e2e/invitations.spec.ts

@@ -0,0 +1,93 @@
+import { expect, test } from '@playwright/test';
+
+import { contextForUser, latestMailFor, tokenFromMail } from './helpers';
+
+/**
+ * Peer invitations (issue #332), the full loop through the UI: a user
+ * invites an address, registration is closed, the invitee registers
+ * through the mailed link anyway, verifies, and the inviter sees the
+ * invitation accepted. Needs Mailpit like the auth pack.
+ */
+const MAILPIT_URL = process.env.E2E_MAILPIT_URL;
+test.skip(!MAILPIT_URL, 'requires a Mailpit instance (E2E_MAILPIT_URL)');
+
+const BASE_URL = process.env.E2E_BASE_URL ?? 'http://localhost:5173';
+
+test('invite -> closed registration -> signup through the link -> accepted', async ({
+  browser,
+  page,
+}) => {
+  const stamp = Date.now().toString(36);
+  const invitee = `invited-${stamp}@dorfteich.test`;
+
+  const admin = await contextForUser(browser, BASE_URL, 'fixture-admin');
+  const inviter = await contextForUser(browser, BASE_URL, 'fixture-user');
+  await admin.request.patch('/api/v1/admin/settings', {
+    data: { 'auth.registrationMode': 'closed' },
+  });
+  try {
+    // Invite through the settings UI.
+    const settingsPage = await inviter.newPage();
+    await settingsPage.goto('/settings');
+    const section = settingsPage.locator('.invitations');
+    await section.getByLabel(/e-mail/i).fill(invitee);
+    await section.getByRole('button', { name: /^(invite|einladen)$/i }).click();
+    await expect(section.locator('.invitations__sent')).toHaveText(/sent|verschickt/i);
+    const row = section.locator(`.invitation-row[data-email="${invitee}"]`);
+    await expect(row.locator('.invitation-row__status')).toHaveText(/open|offen/i);
+
+    // Plain signup is closed…
+    await page.goto('/signup');
+    await expect(page.locator('.form-banner')).toHaveText(/closed|geschlossen/i);
+
+    // …but the mailed link opens the form, inviter banner and prefill included.
+    const mail = await latestMailFor(MAILPIT_URL!, invitee);
+    const invitationToken = /invitation=([A-Za-z0-9_-]+)/.exec(mail.text)?.[1];
+    expect(invitationToken).toBeTruthy();
+    await page.goto(`/signup?invitation=${invitationToken}`);
+    await expect(page.locator('.signup-invitation__banner')).toBeVisible();
+    await expect(page.getByLabel(/e-mail/i)).toHaveValue(invitee);
+    const username = `invited-${stamp}`;
+    await page.getByLabel(/username|benutzername/i).fill(username);
+    await page.getByLabel(/display name|anzeigename/i).fill('Invited Guest');
+    await page.getByLabel(/^password|^passwort/i).fill('ein einladungs passwort 1');
+    await page.getByRole('button', { name: /register|registrieren/i }).click();
+    await expect(page.getByRole('heading', { name: /inbox|postfach/i })).toBeVisible();
+
+    // The usual verification still applies (the link proves nothing about
+    // the mailbox). Two mails went to this address — poll for the second.
+    let verifyToken = '';
+    await expect(async () => {
+      const verifyMail = await latestMailFor(MAILPIT_URL!, invitee);
+      expect(verifyMail.text).toContain('/verify-email');
+      verifyToken = tokenFromMail(verifyMail.text);
+    }).toPass();
+    await page.goto(`/verify-email?token=${verifyToken}`);
+    await expect(page.getByRole('heading', { name: /confirmed|bestätigt/i })).toBeVisible();
+
+    // The inviter sees the acceptance; the used link is dead.
+    await settingsPage.reload();
+    await expect(
+      settingsPage
+        .locator(`.invitation-row[data-email="${invitee}"]`)
+        .locator('.invitation-row__status'),
+    ).toHaveText(/accepted|angenommen/i);
+    await page.goto(`/signup?invitation=${invitationToken}`);
+    await expect(page.locator('.signup-invitation__invalid')).toBeVisible();
+
+    // Revoke flow through the UI: a second invitation dies by revoke.
+    const second = `revoked-${stamp}@dorfteich.test`;
+    await section.getByLabel(/e-mail/i).fill(second);
+    await section.getByRole('button', { name: /^(invite|einladen)$/i }).click();
+    const secondRow = section.locator(`.invitation-row[data-email="${second}"]`);
+    await expect(secondRow.locator('.invitation-row__status')).toHaveText(/open|offen/i);
+    await secondRow.getByRole('button', { name: /revoke|widerrufen/i }).click();
+    await expect(secondRow.locator('.invitation-row__status')).toHaveText(/revoked|widerrufen/i);
+  } finally {
+    await admin.request.patch('/api/v1/admin/settings', {
+      data: { 'auth.registrationMode': 'open' },
+    });
+    await admin.close();
+    await inviter.close();
+  }
+});

apps/web/e2e/legal.spec.ts

@@ -63,7 +63,11 @@ test('the admin form previews and publishes the privacy policy', async ({ browse
   await expect(editor.locator('.legal-editor__preview strong')).toHaveText('only what is needed');
 
   await page.getByRole('button', { name: /save legal pages|rechtsseiten speichern/i }).click();
-  await expect(page.getByRole('status')).toBeVisible();
+  // Auf den Abschnitt gescopet: seit der Schriftverwaltung (#304) hat /admin
+  // weitere Live-Regionen (Upload-Fortschritt), und ein seitenweites
+  // getByRole('status') wäre mehrdeutig. Gemeint war immer die
+  // Erfolgsmeldung DIESES Formulars.
+  await expect(page.locator('.legal-settings').getByRole('status')).toBeVisible();
   await admin.close();
 
   const anonymous = await browser.newContext({ baseURL: BASE_URL });

apps/web/e2e/markdown.spec.ts

@@ -108,6 +108,102 @@ test('a plain-text paste is not mangled into rich structure', async ({ browser }
   await context.close();
 });
 
+test('a Markdown table pasted with code-editor styling HTML becomes a table (issue #339)', async ({
+  browser,
+}) => {
+  const context = await contextForUser(browser, BASE_URL, 'fixture-user');
+  const { pondSlug, pageSlug } = await createPage(context, `E2E MD TablePaste ${Date.now()}`);
+  const page = await context.newPage();
+
+  await page.goto(`/p/${pondSlug}/${pageSlug}`);
+  await enterEditMode(page);
+  await page.locator('.ProseMirror').click();
+
+  // VS Code (copyWithSyntaxHighlighting) ships the plain text a second time
+  // as styled div/span HTML — exactly the flavor that used to shadow the
+  // Markdown conversion.
+  await page.evaluate(() => {
+    const el = document.querySelector('.ProseMirror');
+    const dataTransfer = new DataTransfer();
+    dataTransfer.setData('text/plain', '| A | B |\n| --- | --- |\n| 1 | 2 |');
+    dataTransfer.setData(
+      'text/html',
+      '<meta charset="utf-8"><div style="color:#d4d4d4;background-color:#1e1e1e;">' +
+        '<div><span style="color:#d4d4d4;">| A | B |</span></div>' +
+        '<div><span style="color:#d4d4d4;">| --- | --- |</span></div>' +
+        '<div><span style="color:#d4d4d4;">| 1 | 2 |</span></div></div>',
+    );
+    el!.dispatchEvent(
+      new ClipboardEvent('paste', { clipboardData: dataTransfer, bubbles: true, cancelable: true }),
+    );
+  });
+
+  const content = page.locator('.ProseMirror');
+  await expect(content.locator('table')).toHaveCount(1);
+  await expect(content.locator('th').first()).toHaveText('A');
+  await expect(content.locator('td').first()).toHaveText('1');
+
+  await context.close();
+});
+
+test('a Markdown table pasted into a code block stays verbatim text (issue #339)', async ({
+  browser,
+}) => {
+  const context = await contextForUser(browser, BASE_URL, 'fixture-user');
+  const { pondSlug, pageSlug } = await createPage(context, `E2E MD CodePaste ${Date.now()}`);
+  const page = await context.newPage();
+
+  await page.goto(`/p/${pondSlug}/${pageSlug}`);
+  await enterEditMode(page);
+  await page.locator('.ProseMirror').click();
+  await page.getByRole('button', { name: /code block|codeblock/i }).click();
+
+  await page.evaluate(() => {
+    const el = document.querySelector('.ProseMirror');
+    const dataTransfer = new DataTransfer();
+    dataTransfer.setData('text/plain', '| A | B |\n| --- | --- |\n| 1 | 2 |');
+    el!.dispatchEvent(
+      new ClipboardEvent('paste', { clipboardData: dataTransfer, bubbles: true, cancelable: true }),
+    );
+  });
+
+  const content = page.locator('.ProseMirror');
+  await expect(content.locator('table')).toHaveCount(0);
+  await expect(content.locator('pre')).toContainText('| A | B |');
+
+  await context.close();
+});
+
+test('typing a Markdown table header plus separator creates a table (issue #339)', async ({
+  browser,
+}) => {
+  const context = await contextForUser(browser, BASE_URL, 'fixture-user');
+  const { pondSlug, pageSlug } = await createPage(context, `E2E MD TableType ${Date.now()}`);
+  const page = await context.newPage();
+
+  await page.goto(`/p/${pondSlug}/${pageSlug}`);
+  await enterEditMode(page);
+  const content = page.locator('.ProseMirror');
+  await content.click();
+
+  await page.keyboard.type('| Name | Rolle |');
+  await page.keyboard.press('Enter');
+  await page.keyboard.type('| --- | --- |');
+  await expect(content).toContainText('| --- | --- |');
+  await page.keyboard.press('Enter');
+
+  await expect(content.locator('table')).toHaveCount(1);
+  await expect(content.locator('th').first()).toHaveText('Name');
+  await expect(content).not.toContainText('| --- | --- |');
+
+  // The cursor lands in the table; Tab from the last header cell appends the
+  // first body row (#338), so typing continues seamlessly.
+  await page.keyboard.type('x');
+  await expect(content.locator('th').first()).toContainText('x');
+
+  await context.close();
+});
+
 test('page menu downloads the page as Markdown matching its content', async ({ browser }) => {
   const context = await contextForUser(browser, BASE_URL, 'fixture-user');
   const { pondSlug, pageSlug, pageId } = await createPage(context, `E2E MD Export ${Date.now()}`);

apps/web/e2e/permission-matrix.spec.ts

@@ -173,10 +173,14 @@ test('page read & edit — the 404-vs-403 policy holds per subject', async () =>
 });
 
 test('sidebar list is filtered to each subject’s visible pages', async () => {
-  expect(await listCount(f.admin.request, f.pondId)).toBe(3);
-  expect(await listCount(f.owner.request, f.pondId)).toBe(3);
-  expect(await listCount(f.reader.request, f.pondId)).toBe(3);
-  expect(await listCount(f.editor.request, f.pondId)).toBe(2); // secret hidden
+  // Three fixture pages plus the pond's own start page (issue #302), which
+  // every pond created through the api now carries. It is an ordinary page
+  // with no grant of its own, so it follows the pond-wide permissions: the
+  // outsider, who reaches only the explicitly public page, still sees one.
+  expect(await listCount(f.admin.request, f.pondId)).toBe(4);
+  expect(await listCount(f.owner.request, f.pondId)).toBe(4);
+  expect(await listCount(f.reader.request, f.pondId)).toBe(4);
+  expect(await listCount(f.editor.request, f.pondId)).toBe(3); // secret hidden
   expect(await listCount(f.outsider.request, f.pondId)).toBe(1); // only the public page
   // Anonymous cannot hit the authenticated list endpoint at all.
   expect(await listCount(f.anon, f.pondId)).toBe(401);

apps/web/e2e/settings-nav.spec.ts

@@ -28,8 +28,9 @@ test('user settings show the jump nav and clicking scrolls + activates', async (
   await expect(nav).toBeVisible();
   const links = nav.locator('.settings-nav__link');
   // Profile, password, sessions, watches, API tokens, feed tokens, data export.
-  // 8 seit #170 (Bedienung), 9 seit #180 (Erscheinungsbild).
-  await expect(links).toHaveCount(9);
+  // 8 seit #170 (Bedienung), 9 seit #180 (Erscheinungsbild),
+  // 10 seit #332 (Einladungen).
+  await expect(links).toHaveCount(10);
 
   // Jump to the last section: it scrolls into view and becomes active.
   const last = links.last();

apps/web/e2e/vs-nfd-marking.spec.ts

@@ -34,7 +34,7 @@ test('mode marked: card, checkbox marking, and point-of-choice marking', async (
   // select value — compliant choice clears it, violating choice brings it
   // back, no save in between.
   const regField = page.locator('label.field', {
-    has: page.locator('select[name="auth.registrationMode"]'),
+    has: page.locator('select[name="registrationMode"]'),
   });
   const regSelect = regField.locator('select');
   await regSelect.selectOption('open');
@@ -72,7 +72,7 @@ test('mode hidden: rows disappear, notes mark the hiding, a11y clean', async ({
 
   // Value-listed control: the compliant registration mode keeps only its
   // compliant choice (seed leaves it open = violating? then all options).
-  const regSelect = page.locator('select[name="auth.registrationMode"]');
+  const regSelect = page.locator('select[name="registrationMode"]');
   const regField = page.locator('label.field', { has: regSelect });
   const optionCount = await regSelect.locator('option').count();
   const marked = await regField.locator('.vs-nfd-mark').count();

apps/web/index.html

@@ -10,6 +10,13 @@
     <meta name="theme-color" media="(prefers-color-scheme: light)" content="#2f6f4f" />
     <meta name="theme-color" media="(prefers-color-scheme: dark)" content="#10161d" />
     <title>Dorfteich</title>
+    <!-- Static link, dynamic resource (issue #306): the api answers with the
+         operator's favicon or the shipped default, so this href never has to
+         change and index.html stays a static file. An attribute like `lang`
+         cannot be indirected this way — that is #179's problem, not this
+         one's. -->
+    <link rel="icon" type="image/png" href="/api/v1/branding/favicon" />
+    <link rel="apple-touch-icon" href="/api/v1/branding/favicon?size=180" />
     <!-- Classic (non-module) script: executes during head parsing, before
          first paint and before the deferred module bundle. External file
          because the prod CSP forbids inline scripts (issue #180). -->

apps/web/nginx.conf

@@ -1,3 +1,23 @@
+# The SPA shell's `lang` attribute, negotiated from the request (issue #179,
+# WCAG 3.1.1). `apps/web/index.html` is a static file with a hard `lang="en"`;
+# the app corrects it at runtime (#163), but a crawler or a no-JS visit of an
+# SPA route — which nginx answers with index.html — would see `en` forever,
+# even for German content.
+#
+# Only the FIRST tag of Accept-Language decides, which is what "the browser's
+# preferred language" means and mirrors #163's semantics. `de-CH` counts as
+# German; `en-US,de` does not, because that visitor asked for English first.
+#
+# Known limit, documented rather than worked around: nginx does not know
+# `instance.defaultLocale` from the database, so a visitor with no (or an
+# unlisted) Accept-Language gets `en` even on a German instance. For PUBLIC
+# content that is not the authoritative rendering anyway — the api's server
+# shell (`/api/v1/public/...`) renders those with the instance locale.
+map $http_accept_language $spa_lang {
+    default en;
+    ~*^de    de;
+}
+
 # SPA serving: static assets with long-lived caching, everything else
 # falls back to index.html (client-side routing).
 server {
@@ -34,6 +54,17 @@ server {
         # zero-third-party-request guarantee (security.md) is unaffected.
         add_header Content-Security-Policy "default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline'; font-src 'self' data:; img-src 'self' data: blob:; connect-src 'self'; worker-src 'self'; manifest-src 'self'; object-src 'none'; base-uri 'self'; frame-ancestors 'self'" always;
         add_header X-Content-Type-Options "nosniff" always;
+        # The shell's language (issue #179). Only the html document is
+        # rewritten, and only its first match — `<html lang="en">` is the
+        # first and only occurrence in index.html. Everything else this
+        # location serves passes through untouched.
+        sub_filter_types text/html;
+        sub_filter_once on;
+        sub_filter 'lang="en"' 'lang="$spa_lang"';
+        # The response now depends on a request header, so shared caches must
+        # not serve one language's copy to the other. This location is
+        # `no-cache` anyway; the header states the dependency correctly.
+        add_header Vary "Accept-Language" always;
         try_files $uri /index.html;
     }
 }

apps/web/src/access/AccessRulesManager.tsx

@@ -16,6 +16,7 @@ import { ApiError, apiGet } from '../lib/api';
 import { usePondLabels } from '../labels/use-pond-labels';
 import { usePondMembers } from '../members/use-pond-members';
 import { useAccessRules, useAccessRuleMutations } from './use-access-rules';
+import { IconButton } from '../components/IconButton';
 
 type ScopedType = 'label' | 'page';
 
@@ -238,15 +239,14 @@ export function AccessRulesManager({ pondId }: { pondId: string }): React.JSX.El
             {error}
           </p>
         )}
-        <button
-          className="icon-button rule-add__submit"
+        <IconButton
+          className="rule-add__submit"
           type="submit"
           disabled={!canSubmit}
-          aria-label={t('add.submit')}
-          title={t('add.submit')}
+          label={t('add.submit')}
         >
           <Plus aria-hidden />
-        </button>
+        </IconButton>
       </form>
 
       {rules.length === 0 ? (
@@ -260,15 +260,13 @@ export function AccessRulesManager({ pondId }: { pondId: string }): React.JSX.El
                 {group.rules.map((rule) => (
                   <li key={rule.id} className="rule-item">
                     <span className="rule-sentence">{ruleSentence(rule, t)}</span>
-                    <button
-                      type="button"
-                      className="icon-button rule-remove"
-                      aria-label={t('remove')}
-                      title={t('remove')}
+                    <IconButton
+                      className="rule-remove"
+                      label={t('remove')}
                       onClick={() => void mutations.remove(rule.id)}
                     >
                       <Trash2 aria-hidden />
-                    </button>
+                    </IconButton>
                   </li>
                 ))}
               </ul>

apps/web/src/api-tokens/ApiTokensSection.tsx

@@ -172,52 +172,54 @@ function TokenList({ tokens }: { tokens: ApiTokenView[] }): React.JSX.Element {
   return (
     <>
       <FormError error={error} />
-      <table className="table api-tokens__table">
-        <thead>
-          <tr>
-            <th>{t('fields.name')}</th>
-            <th>{t('fields.scope')}</th>
-            <th>{t('fields.ponds')}</th>
-            <th>{t('list.created')}</th>
-            <th>{t('list.lastUsed')}</th>
-            <th>{t('list.expires')}</th>
-            <th>{t('list.status')}</th>
-            <th>
-              <span className="visually-hidden">{t('common:tableActions')}</span>
-            </th>
-          </tr>
-        </thead>
-        <tbody>
-          {tokens.map((token) => (
-            <tr key={token.id}>
-              <td>{token.name}</td>
-              <td>{token.scope === 'write' ? t('fields.scopeWrite') : t('fields.scopeRead')}</td>
-              <td>
-                {token.ponds.length === 0
-                  ? t('list.allPonds')
-                  : token.ponds.map((pond) => pond.name).join(', ')}
-              </td>
-              <td>{new Date(token.createdAt).toLocaleDateString()}</td>
-              <td>
-                {token.lastUsedAt ? new Date(token.lastUsedAt).toLocaleString() : t('list.never')}
-              </td>
-              <td>{token.expiresAt ? new Date(token.expiresAt).toLocaleDateString() : '—'}</td>
-              <td>{t(`list.${statusOf(token)}`)}</td>
-              <td>
-                {!token.revokedAt && (
-                  <button
-                    type="button"
-                    className="button api-tokens__revoke"
-                    onClick={() => void revoke(token.id)}
-                  >
-                    {t('list.revoke')}
-                  </button>
-                )}
-              </td>
+      <div className="table-scroll" tabIndex={0} role="region" aria-label={t('section.title')}>
+        <table className="table api-tokens__table">
+          <thead>
+            <tr>
+              <th>{t('fields.name')}</th>
+              <th>{t('fields.scope')}</th>
+              <th>{t('fields.ponds')}</th>
+              <th>{t('list.created')}</th>
+              <th>{t('list.lastUsed')}</th>
+              <th>{t('list.expires')}</th>
+              <th>{t('list.status')}</th>
+              <th>
+                <span className="visually-hidden">{t('common:tableActions')}</span>
+              </th>
             </tr>
-          ))}
-        </tbody>
-      </table>
+          </thead>
+          <tbody>
+            {tokens.map((token) => (
+              <tr key={token.id}>
+                <td>{token.name}</td>
+                <td>{token.scope === 'write' ? t('fields.scopeWrite') : t('fields.scopeRead')}</td>
+                <td>
+                  {token.ponds.length === 0
+                    ? t('list.allPonds')
+                    : token.ponds.map((pond) => pond.name).join(', ')}
+                </td>
+                <td>{new Date(token.createdAt).toLocaleDateString()}</td>
+                <td>
+                  {token.lastUsedAt ? new Date(token.lastUsedAt).toLocaleString() : t('list.never')}
+                </td>
+                <td>{token.expiresAt ? new Date(token.expiresAt).toLocaleDateString() : '—'}</td>
+                <td>{t(`list.${statusOf(token)}`)}</td>
+                <td>
+                  {!token.revokedAt && (
+                    <button
+                      type="button"
+                      className="button api-tokens__revoke"
+                      onClick={() => void revoke(token.id)}
+                    >
+                      {t('list.revoke')}
+                    </button>
+                  )}
+                </td>
+              </tr>
+            ))}
+          </tbody>
+        </table>
+      </div>
     </>
   );
 }

apps/web/src/api-tokens/FeedTokensSection.tsx

@@ -85,32 +85,38 @@ export function FeedTokensSection(): React.JSX.Element {
       )}
       {tokens.data && tokens.data.length === 0 && <p>{t('feed.empty')}</p>}
       {tokens.data && tokens.data.length > 0 && (
-        <table className="table">
-          <thead>
-            <tr>
-              <th>{t('fields.name')}</th>
-              <th>{t('list.created')}</th>
-              <th>{t('list.lastUsed')}</th>
-              <th>
-                <span className="visually-hidden">{t('common:tableActions')}</span>
-              </th>
-            </tr>
-          </thead>
-          <tbody>
-            {tokens.data.map((token) => (
-              <tr key={token.id}>
-                <td>{token.name}</td>
-                <td>{formatTime(token.createdAt)}</td>
-                <td>{token.lastUsedAt ? formatTime(token.lastUsedAt) : '—'}</td>
-                <td>
-                  <button type="button" className="linklike" onClick={() => void remove(token.id)}>
-                    {t('feed.delete')}
-                  </button>
-                </td>
+        <div className="table-scroll" tabIndex={0} role="region" aria-label={t('feed.title')}>
+          <table className="table">
+            <thead>
+              <tr>
+                <th>{t('fields.name')}</th>
+                <th>{t('list.created')}</th>
+                <th>{t('list.lastUsed')}</th>
+                <th>
+                  <span className="visually-hidden">{t('common:tableActions')}</span>
+                </th>
               </tr>
-            ))}
-          </tbody>
-        </table>
+            </thead>
+            <tbody>
+              {tokens.data.map((token) => (
+                <tr key={token.id}>
+                  <td>{token.name}</td>
+                  <td>{formatTime(token.createdAt)}</td>
+                  <td>{token.lastUsedAt ? formatTime(token.lastUsedAt) : '—'}</td>
+                  <td>
+                    <button
+                      type="button"
+                      className="linklike"
+                      onClick={() => void remove(token.id)}
+                    >
+                      {t('feed.delete')}
+                    </button>
+                  </td>
+                </tr>
+              ))}
+            </tbody>
+          </table>
+        </div>
       )}
     </section>
   );

apps/web/src/branding/BrandLogo.tsx

@@ -0,0 +1,58 @@
+import { Link } from 'react-router-dom';
+
+import { useCurrentPondRoute } from '../layout/use-pond-route';
+import { logoUrl, usePondFavicon, useResolvedBranding } from './use-branding';
+import { usePondId } from './use-pond-id';
+
+/**
+ * The identity at the top of the sidebar (issues #306/#307): the pond's own
+ * logo when it has one, else the instance's, else the instance name as text.
+ *
+ * Its accessible name follows the LEVEL the logo came from — a pond logo is
+ * named by the pond, an instance logo by the instance. For a screen reader
+ * this is the link home, and a link's name has to say where it goes; keeping
+ * the instance name on a pond logo would announce the wrong destination.
+ *
+ * Both variants are rendered and one is hidden by CSS (`:root[data-theme]`),
+ * not by JavaScript: `theme-init.js` resolves the theme before first paint, so
+ * the correct logo is the one painted. A logo set belongs to ONE level and is
+ * never mixed across levels — see `resolveBranding`.
+ */
+export function BrandLogo(): React.JSX.Element | null {
+  const { pondSlug } = useCurrentPondRoute();
+  const { pondId, pondName } = usePondId(pondSlug);
+  const { resolved, instanceName, pondId: logoPond } = useResolvedBranding(pondId);
+  usePondFavicon(pondId, resolved.faviconLevel === 'pond');
+
+  const name = resolved.logoLevel === 'pond' ? (pondName ?? instanceName) : instanceName;
+  if (!instanceName && resolved.logoLevel === 'none') return null;
+
+  return (
+    <Link to="/" className="brand-logo" aria-label={name}>
+      {resolved.logo || resolved.logoDark ? (
+        <>
+          {resolved.logo && (
+            <img
+              className={`brand-logo__img brand-logo__img--light${resolved.logoDark ? '' : ' brand-logo__img--both'}`}
+              src={logoUrl('light', resolved.logo.hash, logoPond)}
+              width={resolved.logo.width}
+              height={resolved.logo.height}
+              alt=""
+            />
+          )}
+          {resolved.logoDark && (
+            <img
+              className={`brand-logo__img brand-logo__img--dark${resolved.logo ? '' : ' brand-logo__img--both'}`}
+              src={logoUrl('dark', resolved.logoDark.hash, logoPond)}
+              width={resolved.logoDark.width}
+              height={resolved.logoDark.height}
+              alt=""
+            />
+          )}
+        </>
+      ) : (
+        <span className="brand-logo__name">{name}</span>
+      )}
+    </Link>
+  );
+}

apps/web/src/branding/CropField.tsx

@@ -0,0 +1,173 @@
+import { BRANDING_SOURCE_TYPES } from '@dorfteich/shared';
+import { useEffect, useRef, useState } from 'react';
+import { useTranslation } from 'react-i18next';
+
+import { Field } from '../components/forms';
+import { CropRect, clampCrop, drawCrop, initialCrop, loadImage, outputSize } from './crop';
+
+/**
+ * Pick an image, crop it, see the result (issue #306).
+ *
+ * The crop is driven by NUMBER INPUTS, not by dragging. A drag-only cropper
+ * excludes keyboard and switch users outright, and a number input is
+ * arrow-key operable, screen-reader readable and announces its value without
+ * any custom aria plumbing — the accessible option is also the simpler one.
+ * The preview canvas is a picture of the result, never the control.
+ *
+ * The resulting pixel dimensions are stated in TEXT next to it, so the outcome
+ * does not depend on seeing the frame.
+ */
+export function CropField({
+  idPrefix,
+  square,
+  maxEdge,
+  onChange,
+}: {
+  idPrefix: string;
+  /** Favicons are square by construction; a logo keeps its own proportions. */
+  square: boolean;
+  maxEdge: number;
+  /** Called with the rendering canvas whenever the crop changes, so the
+   *  parent can encode PNGs from it on submit. Null = nothing selected. */
+  onChange: (canvas: HTMLCanvasElement | null) => void;
+}): React.JSX.Element {
+  const { t } = useTranslation('branding');
+  const [image, setImage] = useState<HTMLImageElement | null>(null);
+  const [crop, setCrop] = useState<CropRect | null>(null);
+  const [error, setError] = useState<string | null>(null);
+  const canvasRef = useRef<HTMLCanvasElement | null>(null);
+
+  const out = image && crop ? outputSize(crop, maxEdge) : null;
+
+  // Held in a ref so the redraw depends on the crop alone: callers pass an
+  // inline arrow, whose identity changes every render and would otherwise
+  // repaint the canvas on every keystroke in the surrounding form.
+  const notifyRef = useRef(onChange);
+  notifyRef.current = onChange;
+
+  useEffect(() => {
+    const canvas = canvasRef.current;
+    if (!canvas || !image || !crop) {
+      notifyRef.current(null);
+      return;
+    }
+    // Derived inside the effect: `outputSize` returns a fresh object every
+    // render, so as a dependency it would never compare equal.
+    drawCrop(image, crop, outputSize(crop, maxEdge), canvas);
+    notifyRef.current(canvas);
+  }, [image, crop, maxEdge]);
+
+  async function choose(file: File | undefined): Promise<void> {
+    setError(null);
+    if (!file) {
+      setImage(null);
+      setCrop(null);
+      return;
+    }
+    if (!(BRANDING_SOURCE_TYPES as readonly string[]).includes(file.type)) {
+      setImage(null);
+      setCrop(null);
+      // SVG is the one an operator is most likely to try, and it is refused
+      // on purpose (it can carry script) — say which types work instead.
+      setError(file.type === 'image/svg+xml' ? 'branding_svg_rejected' : 'branding_not_an_image');
+      return;
+    }
+    try {
+      const loaded = await loadImage(file);
+      setImage(loaded);
+      setCrop(initialCrop(loaded, square));
+    } catch {
+      setError('branding_not_an_image');
+    }
+  }
+
+  function update(patch: Partial<CropRect>): void {
+    if (!image || !crop) return;
+    const next = { ...crop, ...patch };
+    // A square crop has one size, so width and height move together.
+    if (square && patch.width !== undefined) next.height = patch.width;
+    setCrop(clampCrop(next, image));
+  }
+
+  return (
+    <div className="crop-field">
+      <Field label={t('crop.file')} hint={t('crop.fileHint')} error={error ?? undefined}>
+        <input
+          type="file"
+          accept={BRANDING_SOURCE_TYPES.join(',')}
+          onChange={(event) => void choose(event.target.files?.[0])}
+        />
+      </Field>
+
+      {image && crop && out && (
+        <>
+          <div className="crop-field__controls">
+            <Field label={t('crop.x')}>
+              <input
+                type="number"
+                id={`${idPrefix}-x`}
+                min={0}
+                max={image.width - crop.width}
+                value={crop.x}
+                onChange={(event) => update({ x: Number(event.target.value) })}
+              />
+            </Field>
+            <Field label={t('crop.y')}>
+              <input
+                type="number"
+                id={`${idPrefix}-y`}
+                min={0}
+                max={image.height - crop.height}
+                value={crop.y}
+                onChange={(event) => update({ y: Number(event.target.value) })}
+              />
+            </Field>
+            <Field label={square ? t('crop.size') : t('crop.width')}>
+              <input
+                type="number"
+                id={`${idPrefix}-w`}
+                min={1}
+                max={square ? Math.min(image.width, image.height) : image.width}
+                value={crop.width}
+                onChange={(event) => update({ width: Number(event.target.value) })}
+              />
+            </Field>
+            {!square && (
+              <Field label={t('crop.height')}>
+                <input
+                  type="number"
+                  id={`${idPrefix}-h`}
+                  min={1}
+                  max={image.height}
+                  value={crop.height}
+                  onChange={(event) => update({ height: Number(event.target.value) })}
+                />
+              </Field>
+            )}
+            <button
+              type="button"
+              className="linklike"
+              onClick={() => setCrop(initialCrop(image, square))}
+            >
+              {t('crop.reset')}
+            </button>
+          </div>
+
+          <div className="crop-field__preview">
+            <canvas ref={canvasRef} className="crop-field__canvas" />
+            {/* The outcome in words: the frame alone would leave a
+                keyboard-only or screen-reader user guessing. */}
+            <p className="crop-field__result" role="status">
+              {t('crop.result', {
+                width: out.width,
+                height: out.height,
+                sourceWidth: image.width,
+                sourceHeight: image.height,
+              })}
+            </p>
+          </div>
+        </>
+      )}
+    </div>
+  );
+}

apps/web/src/branding/crop.test.ts

@@ -0,0 +1,73 @@
+import { describe, expect, it } from 'vitest';
+
+import { clampCrop, initialCrop, outputSize } from './crop';
+
+/**
+ * The crop arithmetic (issue #306). Pure functions on purpose: the canvas
+ * work is a thin shell around these, and getting the bounds wrong is what
+ * would let a number input produce a rectangle outside the image.
+ */
+describe('initialCrop', () => {
+  it('takes the whole image when the aspect is free', () => {
+    expect(initialCrop({ width: 900, height: 300 }, false)).toEqual({
+      x: 0,
+      y: 0,
+      width: 900,
+      height: 300,
+    });
+  });
+
+  it('centres the largest square that fits', () => {
+    expect(initialCrop({ width: 900, height: 300 }, true)).toEqual({
+      x: 300,
+      y: 0,
+      width: 300,
+      height: 300,
+    });
+  });
+});
+
+describe('outputSize', () => {
+  it('scales the long edge down to the bound and keeps the ratio', () => {
+    expect(outputSize({ x: 0, y: 0, width: 900, height: 300 }, 512)).toEqual({
+      width: 512,
+      height: 171,
+    });
+  });
+
+  it('never scales UP — enlarging would only invent pixels', () => {
+    expect(outputSize({ x: 0, y: 0, width: 120, height: 40 }, 512)).toEqual({
+      width: 120,
+      height: 40,
+    });
+  });
+});
+
+describe('clampCrop', () => {
+  const source = { width: 200, height: 100 };
+
+  it('keeps the rectangle inside the image', () => {
+    expect(clampCrop({ x: 190, y: 90, width: 50, height: 50 }, source)).toEqual({
+      x: 150,
+      y: 50,
+      width: 50,
+      height: 50,
+    });
+  });
+
+  it('never lets a size fall below one pixel or exceed the source', () => {
+    expect(clampCrop({ x: 0, y: 0, width: 0, height: 999 }, source)).toEqual({
+      x: 0,
+      y: 0,
+      width: 1,
+      height: 100,
+    });
+  });
+
+  it('accepts a negative offset by pulling it back to the edge', () => {
+    expect(clampCrop({ x: -30, y: -5, width: 20, height: 20 }, source)).toMatchObject({
+      x: 0,
+      y: 0,
+    });
+  });
+});

apps/web/src/branding/crop.ts

@@ -0,0 +1,106 @@
+/**
+ * Client-side image preparation for branding uploads (issue #306).
+ *
+ * Cropping, scaling and the conversion to PNG happen here on a canvas; the
+ * api receives finished bytes and never decodes an image. That keeps a
+ * decoder away from attacker-supplied bytes and keeps `sharp` (and its
+ * platform binaries) out of the `--network none` offline build.
+ */
+
+export interface CropRect {
+  x: number;
+  y: number;
+  width: number;
+  height: number;
+}
+
+/** Reads a file into an `HTMLImageElement`, rejecting what the browser cannot
+ *  decode — the first line of defence, before anything reaches the api. */
+export function loadImage(file: File): Promise<HTMLImageElement> {
+  return new Promise((resolve, reject) => {
+    const url = URL.createObjectURL(file);
+    const image = new Image();
+    image.onload = () => {
+      URL.revokeObjectURL(url);
+      resolve(image);
+    };
+    image.onerror = () => {
+      URL.revokeObjectURL(url);
+      reject(new Error('image_undecodable'));
+    };
+    image.src = url;
+  });
+}
+
+/** The crop the editor starts with: the largest centred rectangle of the
+ *  wanted aspect that fits the source. */
+export function initialCrop(source: { width: number; height: number }, square: boolean): CropRect {
+  if (!square) return { x: 0, y: 0, width: source.width, height: source.height };
+  const size = Math.min(source.width, source.height);
+  return {
+    x: Math.round((source.width - size) / 2),
+    y: Math.round((source.height - size) / 2),
+    width: size,
+    height: size,
+  };
+}
+
+/** Output size for a crop: scaled down so the longest edge fits `maxEdge`,
+ *  never scaled UP — enlarging would only invent pixels. */
+export function outputSize(crop: CropRect, maxEdge: number): { width: number; height: number } {
+  const longest = Math.max(crop.width, crop.height);
+  const factor = longest > maxEdge ? maxEdge / longest : 1;
+  return {
+    width: Math.max(1, Math.round(crop.width * factor)),
+    height: Math.max(1, Math.round(crop.height * factor)),
+  };
+}
+
+/** Keeps a crop inside the source and above 1px, so number inputs cannot
+ *  produce a rectangle the canvas would refuse. */
+export function clampCrop(crop: CropRect, source: { width: number; height: number }): CropRect {
+  const width = Math.min(Math.max(1, Math.round(crop.width)), source.width);
+  const height = Math.min(Math.max(1, Math.round(crop.height)), source.height);
+  return {
+    width,
+    height,
+    x: Math.min(Math.max(0, Math.round(crop.x)), source.width - width),
+    y: Math.min(Math.max(0, Math.round(crop.y)), source.height - height),
+  };
+}
+
+/** Renders the crop into a canvas at the given output size. */
+export function drawCrop(
+  image: CanvasImageSource,
+  crop: CropRect,
+  out: { width: number; height: number },
+  canvas: HTMLCanvasElement,
+): void {
+  canvas.width = out.width;
+  canvas.height = out.height;
+  const context = canvas.getContext('2d');
+  if (!context) return;
+  context.clearRect(0, 0, out.width, out.height);
+  context.imageSmoothingQuality = 'high';
+  context.drawImage(image, crop.x, crop.y, crop.width, crop.height, 0, 0, out.width, out.height);
+}
+
+/**
+ * The canvas contents as PNG bytes.
+ *
+ * PNG regardless of the source format — which is why the form states that a
+ * JPEG source cannot gain transparency: the alpha channel exists in the
+ * output, but every pixel of a JPEG is opaque, so the background stays.
+ * Conversion cannot invent what was never in the file.
+ */
+export function canvasToPngFile(canvas: HTMLCanvasElement, name: string): Promise<File> {
+  return new Promise((resolve, reject) => {
+    canvas.toBlob((blob) => {
+      if (!blob) {
+        reject(new Error('canvas_encode_failed'));
+        return;
+      }
+      resolve(new File([blob], name, { type: 'image/png' }));
+    }, 'image/png');
+  });
+}

apps/web/src/branding/use-branding.ts

@@ -0,0 +1,91 @@
+import { BrandingView, PondBranding, ResolvedBranding, resolveBranding } from '@dorfteich/shared';
+import { useQuery, useQueryClient } from '@tanstack/react-query';
+import { useEffect } from 'react';
+
+import { apiGet } from '../lib/api';
+
+export const BRANDING_KEY = ['branding'];
+
+/**
+ * The instance branding in force (issue #306).
+ *
+ * Public, so the login screen carries it too — an operator's logo IS visible
+ * to anonymous visitors, which the admin screen says out loud.
+ */
+export function useBranding(): BrandingView | undefined {
+  return useQuery({
+    queryKey: BRANDING_KEY,
+    queryFn: () => apiGet<BrandingView>('/branding'),
+    // Branding changes are rare and the manager invalidates the key itself.
+    staleTime: 5 * 60 * 1000,
+  }).data;
+}
+
+/** URL of a logo variant, with the content hash so a replaced logo is never
+ *  served from cache. `pondId` scopes it to a pond's own asset (issue #307);
+ *  the route never falls back on its own — the CALLER decided which level
+ *  applies, and a silent fallback here would mix variants across levels. */
+export function logoUrl(variant: 'light' | 'dark', hash: string, pondId?: string): string {
+  const pond = pondId ? `&pond=${pondId}` : '';
+  return `/api/v1/branding/logo?variant=${variant}&v=${hash}${pond}`;
+}
+
+/**
+ * The branding in force here: the pond's own, else the instance's, else the
+ * default (issue #307). One helper, in shared, so api and web cannot drift.
+ */
+export function useResolvedBranding(pondId?: string): {
+  resolved: ResolvedBranding;
+  instanceName: string;
+  /** Which level the logo came from — the asset URLs need the pond scope
+   *  exactly when the pond supplied it. */
+  pondId?: string;
+} {
+  const instance = useBranding();
+  const pond = useQuery({
+    queryKey: ['pond', pondId, 'branding'],
+    queryFn: () => apiGet<PondBranding>(`/ponds/${pondId!}/branding`),
+    enabled: Boolean(pondId),
+    staleTime: 5 * 60 * 1000,
+  });
+  const base = instance ?? { logo: null, logoDark: null, favicon: null, instanceName: '' };
+  const resolved = resolveBranding(base, pond.data ?? null);
+  return {
+    resolved,
+    instanceName: base.instanceName,
+    pondId: resolved.logoLevel === 'pond' ? pondId : undefined,
+  };
+}
+
+/**
+ * Points the document's icon at the pond's favicon while a pond is open, and
+ * back at the instance's on leaving (issue #307).
+ *
+ * Accepted and worth stating: the swap necessarily happens AFTER first paint,
+ * so opening a pond link directly shows the instance favicon briefly before it
+ * changes. Avoiding that would mean server-rendering index.html, which is
+ * #179's territory and deliberately out of scope here. In a pinned tab — where
+ * telling ponds apart matters most — the tab is already open, so the swap is
+ * the normal case rather than the exception.
+ *
+ * Driven by the RESOLVED pond, never by the raw route parameter: an unreadable
+ * or non-existent pond slug must not leave a stale icon in the tab.
+ */
+export function usePondFavicon(pondId: string | undefined, hasPondFavicon: boolean): void {
+  useEffect(() => {
+    const link = document.querySelector<HTMLLinkElement>('link[rel="icon"]');
+    if (!link) return undefined;
+    const instanceHref = '/api/v1/branding/favicon';
+    link.href = pondId && hasPondFavicon ? `${instanceHref}?pond=${pondId}` : instanceHref;
+    return () => {
+      link.href = instanceHref;
+    };
+  }, [pondId, hasPondFavicon]);
+}
+
+export function useInvalidateBranding(): () => Promise<void> {
+  const queryClient = useQueryClient();
+  return async () => {
+    await queryClient.invalidateQueries({ queryKey: BRANDING_KEY });
+  };
+}

apps/web/src/branding/use-pond-id.ts

@@ -0,0 +1,21 @@
+import type { PondView } from '@dorfteich/shared';
+import { useQuery } from '@tanstack/react-query';
+
+import { apiGet } from '../lib/api';
+
+/**
+ * The current pond's id and name from its slug (issue #307).
+ *
+ * Shares the sidebar's query key, so the pond is fetched once. Returns
+ * nothing for an unreadable or unknown slug — which is exactly why the
+ * favicon swap is driven by this and not by the raw route parameter: a bad
+ * slug must not leave a stale icon in the tab.
+ */
+export function usePondId(pondSlug: string | null): { pondId?: string; pondName?: string } {
+  const pond = useQuery({
+    queryKey: ['pond', pondSlug],
+    queryFn: () => apiGet<PondView>(`/ponds/${pondSlug!}`),
+    enabled: Boolean(pondSlug),
+  });
+  return { pondId: pond.data?.id, pondName: pond.data?.name };
+}

apps/web/src/components/IconButton.tsx

@@ -1,4 +1,14 @@
 import type { ButtonHTMLAttributes } from 'react';
+import { Link, type LinkProps } from 'react-router-dom';
+
+/** The shared class list behind both controls (issue #300): one place decides
+ * what an icon-only control looks like, so the box, the icon size, the hover
+ * and the focus ring cannot drift apart between a button and a link. */
+function iconClasses(active: boolean | undefined, className: string | undefined): string {
+  return ['icon-button', active ? 'icon-button--active' : '', className ?? '']
+    .filter(Boolean)
+    .join(' ');
+}
 
 interface IconButtonProps extends ButtonHTMLAttributes<HTMLButtonElement> {
   /** Localized accessible name; also shown as the hover tooltip. */
@@ -15,12 +25,42 @@ export function IconButton({
   children,
   ...rest
 }: IconButtonProps): React.JSX.Element {
-  const classes = ['icon-button', active ? 'icon-button--active' : '', className ?? '']
-    .filter(Boolean)
-    .join(' ');
   return (
-    <button type="button" className={classes} aria-label={label} title={label} {...rest}>
+    <button
+      type="button"
+      className={iconClasses(active, className)}
+      aria-label={label}
+      title={label}
+      {...rest}
+    >
       {children}
     </button>
   );
 }
+
+interface IconLinkProps extends LinkProps {
+  /** Localized accessible name; also shown as the hover tooltip. */
+  label: string;
+  active?: boolean;
+}
+
+/**
+ * The navigating twin of {@link IconButton} (issue #300). An icon-only control
+ * that goes somewhere is a link, not a button — but it has to look and focus
+ * exactly like one, which is why both share {@link iconClasses}. Without it the
+ * three navigating icons (pond settings, graph, trash) stayed the one group
+ * that had to glue the class on by hand.
+ */
+export function IconLink({
+  label,
+  active,
+  className,
+  children,
+  ...rest
+}: IconLinkProps): React.JSX.Element {
+  return (
+    <Link className={iconClasses(active, className)} aria-label={label} title={label} {...rest}>
+      {children}
+    </Link>
+  );
+}