Add pond sidebar with page list, sort modes, and pond switcher (#26)

GET /ponds/:id/pages lists a pond's pages ordered by the pond's
persisted sidebarSort setting (alpha/created; manual arrives with #45).
The sidebar consumes it to show the page list with an active-page
highlight, an owner-only sort switch (persists via the existing
PATCH /ponds/:id), and an inline "new page" flow. The top bar gains a
pond switcher; a new /p/:pondSlug route gives it somewhere to land,
redirecting to the pond's first page once loaded. Sidebar collapse
gains a Ctrl/Cmd+\ shortcut and a slightly refined transition.

Closes #26

apps/api/src/pages/pages.controller.ts

@@ -39,6 +39,11 @@ export class PagesController {
     return this.pages.create(request.user!, pondId, input);
   }
 
+  @Get('ponds/:pondId/pages')
+  async list(@Param('pondId') pondId: string, @Req() request: AuthedRequest): Promise<PageView[]> {
+    return this.pages.list(request.user!, pondId);
+  }
+
   @Get('pages/:id')
   async getState(@Param('id') id: string, @Req() request: AuthedRequest): Promise<PageStateView> {
     return this.pages.getState(request.user!, id);
@@ -46,7 +51,7 @@ export class PagesController {
 
   /** Resolves the pond-slug + page-slug pair the `/p/:pondSlug/:pageSlug` route
    * navigates to (issue #25); the pond id must already be known to the caller
-   * (e.g. from `GET /ponds/:slug`). Listing pages by pond arrives with #26. */
+   * (e.g. from `GET /ponds/:slug`). */
   @Get('ponds/:pondId/pages/:slug')
   async getStateBySlug(
     @Param('pondId') pondId: string,

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

@@ -250,6 +250,70 @@ describe.skipIf(!hasTestDb)('pages (e2e, issue #23)', () => {
       .expect(404);
   });
 
+  it('lists pages sorted by the pond sidebar sort mode (issue #26)', async () => {
+    const titles = [`Zebra ${suffix}`, `Apple ${suffix}`, `Mango ${suffix}`];
+    const ids: string[] = [];
+    for (const title of titles) {
+      const res = await api()
+        .post(`/api/v1/ponds/${pondId}/pages`)
+        .set('Cookie', ownerCookie)
+        .send({ title })
+        .expect(201);
+      ids.push(res.body.id as string);
+    }
+    const [zebraId, appleId, mangoId] = ids;
+
+    // Default sort mode is 'alpha'.
+    const alphaList = await api()
+      .get(`/api/v1/ponds/${pondId}/pages`)
+      .set('Cookie', ownerCookie)
+      .expect(200);
+    const alphaOrder = (alphaList.body as { id: string }[])
+      .map((p) => p.id)
+      .filter((id) => ids.includes(id));
+    expect(alphaOrder).toEqual([appleId, mangoId, zebraId]);
+
+    await api()
+      .patch(`/api/v1/ponds/${pondId}`)
+      .set('Cookie', ownerCookie)
+      .send({ sidebarSort: 'created' })
+      .expect(200);
+
+    const createdList = await api()
+      .get(`/api/v1/ponds/${pondId}/pages`)
+      .set('Cookie', ownerCookie)
+      .expect(200);
+    const createdOrder = (createdList.body as { id: string }[])
+      .map((p) => p.id)
+      .filter((id) => ids.includes(id));
+    expect(createdOrder).toEqual([zebraId, appleId, mangoId]);
+
+    // Sort mode is a pond setting, not per-caller: the outsider would see
+    // 'created' order too, but has no access to this pond in the first place.
+    await api().get(`/api/v1/ponds/${pondId}/pages`).set('Cookie', outsiderCookie).expect(404);
+
+    await api()
+      .patch(`/api/v1/ponds/${pondId}`)
+      .set('Cookie', ownerCookie)
+      .send({ sidebarSort: 'alpha' })
+      .expect(200);
+  });
+
+  it('excludes soft-deleted pages from the list', async () => {
+    const created = await api()
+      .post(`/api/v1/ponds/${pondId}/pages`)
+      .set('Cookie', ownerCookie)
+      .send({ title: `Deleted From List ${suffix}` })
+      .expect(201);
+    await api().delete(`/api/v1/pages/${created.body.id}`).set('Cookie', ownerCookie).expect(204);
+
+    const list = await api()
+      .get(`/api/v1/ponds/${pondId}/pages`)
+      .set('Cookie', ownerCookie)
+      .expect(200);
+    expect((list.body as { id: string }[]).some((p) => p.id === created.body.id)).toBe(false);
+  });
+
   it('hides pages in foreign ponds (404, not 403)', async () => {
     const created = await api()
       .post(`/api/v1/ponds/${pondId}/pages`)

apps/api/src/pages/pages.service.ts

@@ -11,7 +11,9 @@ import {
   PageStateView,
   PageView,
   SavePageStateInput,
+  SidebarSortMode,
   UpdatePageInput,
+  pondSettingsSchema,
   slugify,
 } from '@dorfteich/shared';
 import { Page, Prisma, User } from '@prisma/client';
@@ -104,6 +106,27 @@ export class PagesService {
     return page;
   }
 
+  private static readonly SORT_ORDER: Record<SidebarSortMode, Prisma.PageOrderByWithRelationInput> =
+    {
+      alpha: { title: 'asc' },
+      created: { createdAt: 'asc' },
+      // Manual reordering (drag-and-drop) arrives with #45; the fractional
+      // `sortKey` already reflects creation order in the meantime.
+      manual: { sortKey: 'asc' },
+    };
+
+  /** Sidebar page list, ordered per the pond's persisted sort mode (issue #26). */
+  async list(user: User, pondId: string): Promise<PageView[]> {
+    const pond = await this.prisma.pond.findFirst({ where: { id: pondId, deletedAt: null } });
+    this.access.assertCanSee(user, pond);
+    const settings = pondSettingsSchema.parse(pond.settings ?? {});
+    const pages = await this.prisma.page.findMany({
+      where: { pondId, deletedAt: null },
+      orderBy: PagesService.SORT_ORDER[settings.sidebarSort],
+    });
+    return pages.map((page) => this.viewOf(page));
+  }
+
   async create(user: User, pondId: string, input: CreatePageInput): Promise<PageView> {
     const pond = await this.prisma.pond.findFirst({ where: { id: pondId, deletedAt: null } });
     this.access.assertCanModify(user, pond);

apps/web/e2e/sidebar.spec.ts

@@ -0,0 +1,147 @@
+import { expect, test } from '@playwright/test';
+
+import { contextForUser } from './helpers';
+
+/**
+ * Pond sidebar pack (issue #26). Runs against the local dev stack (api +
+ * web), no Mailpit needed. Creates its own pages per test via the api and
+ * navigates straight to `/p/:pondSlug/:pageSlug` (or `/p/:pondSlug`).
+ */
+const BASE_URL = process.env.E2E_BASE_URL ?? 'http://localhost:5173';
+
+async function personalPond(
+  context: Awaited<ReturnType<typeof contextForUser>>,
+): Promise<{ id: string; slug: string }> {
+  const ponds = await context.request.get('/api/v1/ponds');
+  const pond = (await ponds.json()).find((p: { type: string }) => p.type === 'personal');
+  return { id: pond.id, slug: pond.slug };
+}
+
+async function createPage(
+  context: Awaited<ReturnType<typeof contextForUser>>,
+  pondId: string,
+  title: string,
+): Promise<{ id: string; slug: string }> {
+  const created = await context.request.post(`/api/v1/ponds/${pondId}/pages`, {
+    data: { title },
+  });
+  return created.json();
+}
+
+test('sort modes reorder the sidebar page list correctly', async ({ browser }) => {
+  const context = await contextForUser(browser, BASE_URL, 'fixture-user');
+  const pond = await personalPond(context);
+  // Defensive: a previous failed run may have left this fixture pond on a
+  // non-default sort mode.
+  await context.request.patch(`/api/v1/ponds/${pond.id}`, { data: { sidebarSort: 'alpha' } });
+  const suffix = Date.now();
+  await createPage(context, pond.id, `Zebra ${suffix}`);
+  const apple = await createPage(context, pond.id, `Apple ${suffix}`);
+  await createPage(context, pond.id, `Mango ${suffix}`);
+
+  const page = await context.newPage();
+  await page.goto(`/p/${pond.slug}/${apple.slug}`);
+
+  const items = page.locator('.sidebar__pages .sidebar__page');
+  await expect(items.filter({ hasText: `Zebra ${suffix}` })).toBeVisible();
+
+  async function orderOf(titles: string[]): Promise<number[]> {
+    const texts = await items.allTextContents();
+    return titles.map((title) => texts.findIndex((text) => text === title));
+  }
+
+  // Default pond setting is 'alpha': relative order of the three fixture
+  // pages must be ascending regardless of whatever other pages exist.
+  function expectAscending(order: number[]): void {
+    expect(order.every((v, i) => i === 0 || order[i - 1]! < v)).toBe(true);
+  }
+  await expect(async () => {
+    expectAscending(await orderOf([`Apple ${suffix}`, `Mango ${suffix}`, `Zebra ${suffix}`]));
+  }).toPass();
+
+  try {
+    await page.getByLabel(/sort pages|seiten sortieren/i).selectOption('created');
+    await expect(async () => {
+      expectAscending(await orderOf([`Zebra ${suffix}`, `Apple ${suffix}`, `Mango ${suffix}`]));
+    }).toPass();
+
+    // Reload: the sort mode persisted server-side, not just in local state.
+    await page.reload();
+    await expect(page.getByLabel(/sort pages|seiten sortieren/i)).toHaveValue('created');
+    await expect(async () => {
+      expectAscending(await orderOf([`Zebra ${suffix}`, `Apple ${suffix}`, `Mango ${suffix}`]));
+    }).toPass();
+  } finally {
+    // Reset so this fixture pond doesn't leak state into other tests/runs.
+    await page.getByLabel(/sort pages|seiten sortieren/i).selectOption('alpha');
+  }
+
+  await context.close();
+});
+
+test('active page is highlighted in the sidebar', async ({ browser }) => {
+  const context = await contextForUser(browser, BASE_URL, 'fixture-user');
+  const pond = await personalPond(context);
+  const suffix = Date.now();
+  const one = await createPage(context, pond.id, `Active One ${suffix}`);
+  const two = await createPage(context, pond.id, `Active Two ${suffix}`);
+
+  const page = await context.newPage();
+  await page.goto(`/p/${pond.slug}/${one.slug}`);
+
+  const activeLink = page.locator('.sidebar__page--active');
+  await expect(activeLink).toHaveText(`Active One ${suffix}`);
+
+  await page.goto(`/p/${pond.slug}/${two.slug}`);
+  await expect(page.locator('.sidebar__page--active')).toHaveText(`Active Two ${suffix}`);
+
+  await context.close();
+});
+
+test('new-page flow: button opens a title prompt and the editor opens on create', async ({
+  browser,
+}) => {
+  const context = await contextForUser(browser, BASE_URL, 'fixture-user');
+  const pond = await personalPond(context);
+  const suffix = Date.now();
+  const title = `Created via UI ${suffix}`;
+
+  const page = await context.newPage();
+  await page.goto(`/p/${pond.slug}`);
+
+  await page.getByRole('button', { name: /new page|neue seite/i }).click();
+  await page.getByLabel(/title|titel/i).fill(title);
+  await page.getByRole('button', { name: /create|erstellen/i }).click();
+
+  await expect(page).toHaveURL(new RegExp(`/p/${pond.slug}/.+`));
+  await expect(page.locator('.editor-page__title')).toHaveValue(title);
+  await expect(page.locator('.sidebar__page--active')).toHaveText(title);
+
+  await context.close();
+});
+
+test('sidebar collapse state persists per user and via the keyboard shortcut', async ({
+  browser,
+}) => {
+  const context = await contextForUser(browser, BASE_URL, 'fixture-user');
+  const pond = await personalPond(context);
+  const suffix = Date.now();
+  const created = await createPage(context, pond.id, `Collapse Test ${suffix}`);
+
+  const page = await context.newPage();
+  await page.goto(`/p/${pond.slug}/${created.slug}`);
+
+  const sidebar = page.locator('nav.sidebar');
+  await expect(sidebar).toHaveAttribute('aria-hidden', 'false');
+
+  await page.keyboard.press('ControlOrMeta+Backslash');
+  await expect(sidebar).toHaveAttribute('aria-hidden', 'true');
+
+  await page.reload();
+  await expect(sidebar).toHaveAttribute('aria-hidden', 'true');
+
+  await page.keyboard.press('ControlOrMeta+Backslash');
+  await expect(sidebar).toHaveAttribute('aria-hidden', 'false');
+
+  await context.close();
+});

apps/web/src/App.tsx

@@ -6,6 +6,7 @@ import { AdminSettingsPage } from './pages/AdminSettingsPage';
 import { HomePage } from './pages/HomePage';
 import { NotFoundPage } from './pages/NotFoundPage';
 import { PageEditorPage } from './pages/PageEditorPage';
+import { PondHomePage } from './pages/PondHomePage';
 import { SettingsPage } from './pages/SettingsPage';
 import { ForgotPasswordPage } from './pages/auth/ForgotPasswordPage';
 import { LoginPage } from './pages/auth/LoginPage';
@@ -30,6 +31,7 @@ export function App(): React.JSX.Element {
 
         <Route element={<RequireAuth />}>
           <Route path="settings" element={<SettingsPage />} />
+          <Route path="p/:pondSlug" element={<PondHomePage />} />
           <Route path="p/:pondSlug/:pageSlug" element={<PageEditorPage />} />
         </Route>
         <Route element={<RequireSiteAdmin />}>

apps/web/src/layout/AppLayout.tsx

@@ -1,4 +1,4 @@
-import { useState } from 'react';
+import { useEffect, useState } from 'react';
 import { Outlet } from 'react-router-dom';
 
 import { usePersistentState } from '../lib/use-persistent-state';
@@ -11,6 +11,19 @@ export function AppLayout(): React.JSX.Element {
   const [forcedHidden, setForcedHidden] = useState(false);
   const collapsed = sidebarCollapsed || forcedHidden;
 
+  // Ctrl/Cmd+\ toggles the sidebar (same shortcut as Notion), regardless of
+  // which element has focus.
+  useEffect(() => {
+    function handleKeyDown(event: KeyboardEvent): void {
+      if ((event.ctrlKey || event.metaKey) && event.key === '\\') {
+        event.preventDefault();
+        setSidebarCollapsed(!sidebarCollapsed);
+      }
+    }
+    window.addEventListener('keydown', handleKeyDown);
+    return () => window.removeEventListener('keydown', handleKeyDown);
+  }, [sidebarCollapsed, setSidebarCollapsed]);
+
   return (
     <SidebarChromeContext.Provider value={setForcedHidden}>
       <div className="app">

apps/web/src/layout/NewPageForm.tsx

@@ -0,0 +1,64 @@
+import { zodResolver } from '@hookform/resolvers/zod';
+import { CreatePageInput, PageView, createPageInputSchema } from '@dorfteich/shared';
+import { useState } from 'react';
+import { useForm } from 'react-hook-form';
+import { useTranslation } from 'react-i18next';
+import { useNavigate } from 'react-router-dom';
+
+import { Field, FormError } from '../components/forms';
+import { apiPost } from '../lib/api';
+
+interface NewPageFormProps {
+  pondId: string;
+  pondSlug: string;
+  onCreated: () => void;
+  onCancel: () => void;
+}
+
+/** Inline "new page" prompt: title → create → editor opens (issue #26). */
+export function NewPageForm({
+  pondId,
+  pondSlug,
+  onCreated,
+  onCancel,
+}: NewPageFormProps): React.JSX.Element {
+  const { t } = useTranslation();
+  const navigate = useNavigate();
+  const [error, setError] = useState<unknown>(null);
+  const form = useForm<CreatePageInput>({ resolver: zodResolver(createPageInputSchema) });
+
+  const onSubmit = form.handleSubmit(async (input) => {
+    setError(null);
+    try {
+      const page = await apiPost<PageView>(`/ponds/${pondId}/pages`, input);
+      onCreated();
+      navigate(`/p/${pondSlug}/${page.slug}`);
+    } catch (err) {
+      setError(err);
+    }
+  });
+
+  return (
+    <form className="sidebar__new-page-form" onSubmit={(event) => void onSubmit(event)} noValidate>
+      <FormError error={error} />
+      <Field label={t('layout.sidebar.newPageTitle')} error={form.formState.errors.title?.message}>
+        <input
+          type="text"
+          autoFocus
+          {...form.register('title')}
+          onKeyDown={(event) => {
+            if (event.key === 'Escape') onCancel();
+          }}
+        />
+      </Field>
+      <div className="sidebar__new-page-actions">
+        <button type="submit" className="button" disabled={form.formState.isSubmitting}>
+          {t('layout.sidebar.create')}
+        </button>
+        <button type="button" className="linklike" onClick={onCancel}>
+          {t('layout.sidebar.cancel')}
+        </button>
+      </div>
+    </form>
+  );
+}

apps/web/src/layout/PondSwitcher.tsx

@@ -0,0 +1,54 @@
+import type { PondView } from '@dorfteich/shared';
+import { useQuery } from '@tanstack/react-query';
+import { useState } from 'react';
+import { useTranslation } from 'react-i18next';
+import { Link } from 'react-router-dom';
+
+import { useAuth } from '../auth/auth-context';
+import { apiGet } from '../lib/api';
+import { useCurrentPondRoute } from './use-pond-route';
+
+/** Top-bar dropdown to switch between the signed-in user's ponds (issue #26). */
+export function PondSwitcher(): React.JSX.Element | null {
+  const { t } = useTranslation();
+  const { user } = useAuth();
+  const { pondSlug } = useCurrentPondRoute();
+  const [open, setOpen] = useState(false);
+  const ponds = useQuery({
+    queryKey: ['ponds'],
+    queryFn: () => apiGet<PondView[]>('/ponds'),
+    enabled: Boolean(user),
+  });
+
+  if (!ponds.data || ponds.data.length === 0) return null;
+  const current = ponds.data.find((pond) => pond.slug === pondSlug);
+
+  return (
+    <div className="user-menu">
+      <button
+        type="button"
+        className="user-menu__trigger"
+        aria-haspopup="menu"
+        aria-expanded={open}
+        aria-label={t('layout.pondSwitcher.label')}
+        onClick={() => setOpen(!open)}
+      >
+        {current?.name ?? t('layout.pondSwitcher.trigger')}
+      </button>
+      {open && (
+        <div className="user-menu__list" role="menu">
+          {ponds.data.map((pond) => (
+            <Link
+              key={pond.id}
+              role="menuitem"
+              to={`/p/${pond.slug}`}
+              onClick={() => setOpen(false)}
+            >
+              {pond.name}
+            </Link>
+          ))}
+        </div>
+      )}
+    </div>
+  );
+}

apps/web/src/layout/Sidebar.tsx

@@ -1,23 +1,122 @@
+import type { PageView, PondView, SidebarSortMode } from '@dorfteich/shared';
+import { useQuery, useQueryClient } from '@tanstack/react-query';
+import { useState } from 'react';
 import { useTranslation } from 'react-i18next';
+import { Link } from 'react-router-dom';
+
+import { useAuth } from '../auth/auth-context';
+import { apiGet, apiPatch } from '../lib/api';
+import { NewPageForm } from './NewPageForm';
+import { useCurrentPondRoute } from './use-pond-route';
 
 interface SidebarProps {
   collapsed: boolean;
 }
 
+/** Modes offered in the switch; manual reordering (drag-and-drop) arrives with #45. */
+const SORT_MODES: SidebarSortMode[] = ['alpha', 'created'];
+
 /**
- * Left sidebar skeleton. The pond page list (issue #26) replaces the hint
- * text; the collapse behavior and layout contract are final: collapsing
- * must not reflow the main content beyond reclaiming the width.
+ * Left sidebar: the current pond's page list, sort mode, active-page
+ * highlight, and "new page" flow (issue #26). Collapse behavior and the
+ * layout contract (`nav.sidebar`, `aria-hidden`) are unchanged from #4/#25.
  */
 export function Sidebar({ collapsed }: SidebarProps): React.JSX.Element {
   const { t } = useTranslation();
+  const { user } = useAuth();
+  const { pondSlug, pageSlug } = useCurrentPondRoute();
+  const queryClient = useQueryClient();
+  const [creating, setCreating] = useState(false);
+
+  const pond = useQuery({
+    queryKey: ['pond', pondSlug],
+    queryFn: () => apiGet<PondView>(`/ponds/${pondSlug}`),
+    enabled: pondSlug !== null,
+  });
+
+  const pages = useQuery({
+    queryKey: ['pages', pond.data?.id, pond.data?.settings.sidebarSort],
+    queryFn: () => apiGet<PageView[]>(`/ponds/${pond.data!.id}/pages`),
+    enabled: Boolean(pond.data),
+  });
+
+  const isOwner = Boolean(user && pond.data && user.id === pond.data.ownerId);
+
+  async function setSortMode(mode: SidebarSortMode): Promise<void> {
+    if (!pond.data) return;
+    await apiPatch(`/ponds/${pond.data.id}`, { sidebarSort: mode });
+    await queryClient.invalidateQueries({ queryKey: ['pond', pondSlug] });
+  }
+
   return (
     <nav
       className={collapsed ? 'sidebar sidebar--collapsed' : 'sidebar'}
       aria-hidden={collapsed}
       aria-label={t('layout.sidebar.label')}
     >
-      <p className="sidebar__hint">{t('layout.sidebar.placeholder')}</p>
+      {!pond.data ? (
+        <p className="sidebar__hint">{t('layout.sidebar.placeholder')}</p>
+      ) : (
+        <>
+          <div className="sidebar__header">
+            <h2 className="sidebar__pond-name">{pond.data.name}</h2>
+            {isOwner && (
+              <select
+                className="sidebar__sort"
+                aria-label={t('layout.sidebar.sortLabel')}
+                value={pond.data.settings.sidebarSort}
+                onChange={(event) => void setSortMode(event.target.value as SidebarSortMode)}
+              >
+                {SORT_MODES.map((mode) => (
+                  <option key={mode} value={mode}>
+                    {t(`layout.sidebar.sortMode.${mode}`)}
+                  </option>
+                ))}
+              </select>
+            )}
+          </div>
+
+          {pages.data && pages.data.length > 0 ? (
+            <ul className="sidebar__pages">
+              {pages.data.map((p) => (
+                <li key={p.id}>
+                  <Link
+                    to={`/p/${pondSlug}/${p.slug}`}
+                    className={
+                      p.slug === pageSlug ? 'sidebar__page sidebar__page--active' : 'sidebar__page'
+                    }
+                    aria-current={p.slug === pageSlug ? 'page' : undefined}
+                  >
+                    {p.title}
+                  </Link>
+                </li>
+              ))}
+            </ul>
+          ) : (
+            <p className="sidebar__hint">{t('layout.sidebar.empty')}</p>
+          )}
+
+          {creating ? (
+            <NewPageForm
+              pondId={pond.data.id}
+              pondSlug={pondSlug!}
+              onCreated={() => {
+                setCreating(false);
+                void queryClient.invalidateQueries({ queryKey: ['pages', pond.data!.id] });
+              }}
+              onCancel={() => setCreating(false)}
+            />
+          ) : (
+            <button
+              type="button"
+              className="linklike sidebar__new-page"
+              onClick={() => setCreating(true)}
+            >
+              {t('layout.sidebar.newPage')}
+            </button>
+          )}
+        </>
+      )}
     </nav>
   );
 }

apps/web/src/layout/TopBar.tsx

@@ -3,6 +3,7 @@ import { useTranslation } from 'react-i18next';
 import { Link, useNavigate } from 'react-router-dom';
 
 import { useAuth } from '../auth/auth-context';
+import { PondSwitcher } from './PondSwitcher';
 
 interface TopBarProps {
   sidebarCollapsed: boolean;
@@ -36,6 +37,7 @@ export function TopBar({ sidebarCollapsed, onToggleSidebar }: TopBarProps): Reac
       <Link to="/" className="topbar__brand">
         Dorfteich
       </Link>
+      {user && <PondSwitcher />}
       <span className="topbar__spacer" />
       {user ? (
         <div className="user-menu">

apps/web/src/layout/use-pond-route.ts

@@ -0,0 +1,18 @@
+import { useLocation } from 'react-router-dom';
+
+interface PondRoute {
+  pondSlug: string | null;
+  pageSlug: string | null;
+}
+
+/**
+ * The sidebar and top bar render outside the routed `<Outlet>` (they wrap
+ * it), so `useParams` cannot see `:pondSlug`/`:pageSlug` — those only exist
+ * on the nested page routes. Parsing the path directly works regardless of
+ * which route matched underneath.
+ */
+export function useCurrentPondRoute(): PondRoute {
+  const { pathname } = useLocation();
+  const match = /^\/p\/([^/]+)(?:\/([^/]+))?/.exec(pathname);
+  return { pondSlug: match?.[1] ?? null, pageSlug: match?.[2] ?? null };
+}

apps/web/src/pages/PondHomePage.tsx

@@ -0,0 +1,46 @@
+import type { PageView, PondView } from '@dorfteich/shared';
+import { useQuery } from '@tanstack/react-query';
+import { useEffect } from 'react';
+import { useTranslation } from 'react-i18next';
+import { useNavigate, useParams } from 'react-router-dom';
+
+import { FormError } from '../components/forms';
+import { apiGet } from '../lib/api';
+
+/**
+ * Landing route for a pond without a page open yet (`/p/:pondSlug`, e.g.
+ * from the pond switcher). Redirects to the first page per the pond's sort
+ * mode once loaded; an empty pond shows a hint pointing at the sidebar's
+ * "new page" button instead (issue #26).
+ */
+export function PondHomePage(): React.JSX.Element {
+  const { t } = useTranslation();
+  const navigate = useNavigate();
+  const { pondSlug = '' } = useParams<{ pondSlug: string }>();
+
+  const pond = useQuery({
+    queryKey: ['pond', pondSlug],
+    queryFn: () => apiGet<PondView>(`/ponds/${pondSlug}`),
+  });
+  const pages = useQuery({
+    queryKey: ['pages', pond.data?.id, pond.data?.settings.sidebarSort],
+    queryFn: () => apiGet<PageView[]>(`/ponds/${pond.data!.id}/pages`),
+    enabled: Boolean(pond.data),
+  });
+
+  useEffect(() => {
+    if (pages.data && pages.data.length > 0) {
+      navigate(`/p/${pondSlug}/${pages.data[0]!.slug}`, { replace: true });
+    }
+  }, [pages.data, pondSlug, navigate]);
+
+  if (pond.error || pages.error) return <FormError error={pond.error ?? pages.error} />;
+  if (!pond.data || !pages.data || pages.data.length > 0) return <></>;
+
+  return (
+    <div className="pond-home">
+      <h1>{pond.data.name}</h1>
+      <p>{t('pondHome.empty')}</p>
+    </div>
+  );
+}

apps/web/src/styles/base.css

@@ -80,11 +80,14 @@ button {
   background: var(--color-bg-subtle);
   padding: var(--space-4);
   overflow-y: auto;
-  transition: margin-left 0.15s ease-out;
+  transition:
+    margin-left 0.18s ease-out,
+    opacity 0.15s ease-out;
 }
 
 .sidebar--collapsed {
   margin-left: calc(-1 * var(--sidebar-width));
+  opacity: 0;
 }
 
 .sidebar__hint {
@@ -92,6 +95,74 @@ button {
   font-size: 0.9rem;
 }
 
+.sidebar__header {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: var(--space-2);
+  margin-bottom: var(--space-3);
+}
+
+.sidebar__pond-name {
+  font-size: 1rem;
+  margin: 0;
+}
+
+.sidebar__sort {
+  font: inherit;
+  font-size: 0.85rem;
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius);
+  background: var(--color-bg);
+  padding: var(--space-1) var(--space-2);
+}
+
+.sidebar__pages {
+  list-style: none;
+  margin: 0 0 var(--space-3);
+  padding: 0;
+}
+
+.sidebar__page {
+  display: block;
+  padding: var(--space-1) var(--space-2);
+  border-radius: var(--radius);
+  color: var(--color-text);
+  text-decoration: none;
+  font-size: 0.95rem;
+}
+
+.sidebar__page:hover {
+  background: var(--color-bg);
+}
+
+.sidebar__page--active {
+  background: var(--color-bg);
+  font-weight: 600;
+}
+
+.sidebar__new-page {
+  font-size: 0.9rem;
+}
+
+.sidebar__new-page-form {
+  margin-top: var(--space-2);
+}
+
+.sidebar__new-page-form .field {
+  margin-bottom: var(--space-2);
+}
+
+.sidebar__new-page-actions {
+  display: flex;
+  align-items: center;
+  gap: var(--space-3);
+}
+
+.pond-home {
+  max-width: 36rem;
+}
+
 .main {
   flex: 1;
   min-width: 0;

packages/shared/i18n/de/common.json

@@ -4,12 +4,29 @@
       "expand": "Seitenleiste einblenden",
       "collapse": "Seitenleiste ausblenden",
       "label": "Seiten",
-      "placeholder": "Deine Teiche und Seiten erscheinen hier."
+      "placeholder": "Deine Teiche und Seiten erscheinen hier.",
+      "empty": "Noch keine Seiten.",
+      "sortLabel": "Seiten sortieren",
+      "sortMode": {
+        "alpha": "A–Z",
+        "created": "Erstellungsdatum"
+      },
+      "newPage": "+ Neue Seite",
+      "newPageTitle": "Titel",
+      "create": "Erstellen",
+      "cancel": "Abbrechen"
+    },
+    "pondSwitcher": {
+      "label": "Teich wechseln",
+      "trigger": "Teich auswählen"
     },
     "user": {
       "anonymous": "Nicht angemeldet"
     }
   },
+  "pondHome": {
+    "empty": "Dieser Teich hat noch keine Seiten – lege eine über die Seitenleiste an."
+  },
   "home": {
     "title": "Willkommen im Dorfteich",
     "intro": "Dorfteich ist ein Open-Source-Wiki mit Echtzeit-Zusammenarbeit. Diese Instanz wird gerade eingerichtet.",

packages/shared/i18n/en/common.json

@@ -4,12 +4,29 @@
       "expand": "Show sidebar",
       "collapse": "Hide sidebar",
       "label": "Pages",
-      "placeholder": "Your ponds and pages will appear here."
+      "placeholder": "Your ponds and pages will appear here.",
+      "empty": "No pages yet.",
+      "sortLabel": "Sort pages",
+      "sortMode": {
+        "alpha": "A–Z",
+        "created": "Creation date"
+      },
+      "newPage": "+ New page",
+      "newPageTitle": "Title",
+      "create": "Create",
+      "cancel": "Cancel"
+    },
+    "pondSwitcher": {
+      "label": "Switch pond",
+      "trigger": "Select a pond"
     },
     "user": {
       "anonymous": "Not signed in"
     }
   },
+  "pondHome": {
+    "empty": "This pond doesn't have any pages yet — create one from the sidebar."
+  },
   "home": {
     "title": "Welcome to Dorfteich",
     "intro": "Dorfteich is an open-source wiki with real-time collaboration. This instance is being set up.",