diff --git a/src/app/api/v1/bibliothek/[entryId]/route.ts b/src/app/api/v1/bibliothek/[entryId]/route.ts
new file mode 100644
index 0000000..b00cdd5
--- /dev/null
+++ b/src/app/api/v1/bibliothek/[entryId]/route.ts
@@ -0,0 +1,85 @@
+import { z } from "zod";
+import { apiError, readJson, withApi } from "@/lib/api";
+import { prisma } from "@/lib/db";
+import {
+  getNextEpisode,
+  getProgress,
+  moveToTrash,
+  setStatus,
+  updateEntryDetails,
+} from "@/lib/library";
+
+const STATUSES = ["WATCHING", "PAUSED", "COMPLETED", "DROPPED", "WATCHLIST"] as const;
+
+/** GET /api/v1/bibliothek/{id} — ein Eintrag mit Fortschritt und nächster Episode. */
+export const GET = withApi(async (_request, user, context) => {
+  const { entryId } = await context.params;
+  if (!entryId) return apiError("Es fehlt die Kennung des Eintrags.", 400);
+
+  const entry = await prisma.libraryEntry.findFirst({
+    where: { id: entryId, userId: user.id },
+    include: {
+      title: true,
+      tags: { include: { tag: { select: { name: true } } } },
+    },
+  });
+  if (!entry) return apiError("Diesen Eintrag gibt es nicht.", 404);
+
+  const [progress, next] = await Promise.all([
+    getProgress(user.id, entry.id),
+    getNextEpisode(user.id, entry.id),
+  ]);
+
+  return {
+    id: entry.id,
+    status: entry.status,
+    rating: entry.rating,
+    notes: entry.notes,
+    whereToWatch: entry.whereToWatch,
+    favorite: entry.favorite,
+    currentRun: entry.currentRun,
+    tags: entry.tags.map((link) => link.tag.name),
+    title: {
+      id: entry.title.id,
+      title: entry.title.title,
+      type: entry.title.type,
+      tmdbId: entry.title.tmdbId,
+      year: entry.title.releaseDate?.getFullYear() ?? null,
+      genres: entry.title.genres,
+    },
+    progress,
+    nextEpisode: next,
+  };
+});
+
+const patchSchema = z.object({
+  status: z.enum(STATUSES).optional(),
+  rating: z.number().int().min(1).max(10).nullable().optional(),
+  notes: z.string().max(5000).nullable().optional(),
+  whereToWatch: z.string().max(120).nullable().optional(),
+  favorite: z.boolean().optional(),
+});
+
+/** PATCH /api/v1/bibliothek/{id} — Status und Angaben ändern. */
+export const PATCH = withApi(async (request, user, context) => {
+  const { entryId } = await context.params;
+  if (!entryId) return apiError("Es fehlt die Kennung des Eintrags.", 400);
+
+  const { status, ...details } = await readJson(request, patchSchema);
+
+  if (status) await setStatus(user.id, entryId, status);
+  if (Object.keys(details).length > 0) {
+    await updateEntryDetails(user.id, entryId, details);
+  }
+
+  return { ok: true };
+});
+
+/** DELETE /api/v1/bibliothek/{id} — in den Papierkorb legen. */
+export const DELETE = withApi(async (_request, user, context) => {
+  const { entryId } = await context.params;
+  if (!entryId) return apiError("Es fehlt die Kennung des Eintrags.", 400);
+
+  await moveToTrash(user.id, entryId);
+  return { ok: true, message: "In den Papierkorb gelegt." };
+});
diff --git a/src/app/api/v1/bibliothek/[entryId]/sichtungen/route.ts b/src/app/api/v1/bibliothek/[entryId]/sichtungen/route.ts
new file mode 100644
index 0000000..b44d86b
--- /dev/null
+++ b/src/app/api/v1/bibliothek/[entryId]/sichtungen/route.ts
@@ -0,0 +1,93 @@
+import { z } from "zod";
+import { apiError, readJson, withApi } from "@/lib/api";
+import { prisma } from "@/lib/db";
+import {
+  markEpisodesWatched,
+  markMovieWatched,
+  markSeasonWatched,
+  markUpTo,
+  undoWatches,
+  unmarkEpisodes,
+  watchNextEpisode,
+} from "@/lib/library";
+
+/** GET — die Sichtungen eines Eintrags, jüngste zuerst. */
+export const GET = withApi(async (_request, user, context) => {
+  const { entryId } = await context.params;
+  if (!entryId) return apiError("Es fehlt die Kennung des Eintrags.", 400);
+
+  const watches = await prisma.watch.findMany({
+    where: { userId: user.id, entryId },
+    orderBy: { watchedAt: "desc" },
+    take: 500,
+    include: { episode: { select: { seasonNumber: true, episodeNumber: true, name: true } } },
+  });
+
+  return {
+    total: watches.length,
+    items: watches.map((watch) => ({
+      id: watch.id,
+      run: watch.run,
+      watchedAt: watch.watchedAt,
+      minutes: watch.minutes,
+      episode: watch.episode,
+    })),
+  };
+});
+
+const postSchema = z.union([
+  z.object({ action: z.literal("next") }),
+  z.object({ action: z.literal("movie") }),
+  z.object({
+    action: z.literal("episodes"),
+    episodeIds: z.array(z.string().min(1)).min(1).max(500),
+  }),
+  z.object({ action: z.literal("season"), seasonId: z.string().min(1) }),
+  z.object({ action: z.literal("upTo"), episodeId: z.string().min(1) }),
+]);
+
+/**
+ * POST — etwas als gesehen markieren.
+ *
+ * Die Antwort enthält immer `watchIds`. Damit lässt sich die Aktion über
+ * DELETE gezielt zurücknehmen, ohne raten zu müssen, was dazugehörte.
+ */
+export const POST = withApi(async (request, user, context) => {
+  const { entryId } = await context.params;
+  if (!entryId) return apiError("Es fehlt die Kennung des Eintrags.", 400);
+
+  const body = await readJson(request, postSchema);
+
+  switch (body.action) {
+    case "next":
+      return watchNextEpisode(user.id, entryId);
+    case "movie":
+      return markMovieWatched(user.id, entryId);
+    case "episodes":
+      return markEpisodesWatched(user.id, entryId, body.episodeIds);
+    case "season":
+      return markSeasonWatched(user.id, entryId, body.seasonId);
+    case "upTo":
+      return markUpTo(user.id, entryId, body.episodeId);
+  }
+});
+
+const deleteSchema = z.union([
+  z.object({ watchIds: z.array(z.string().min(1)).min(1).max(500) }),
+  z.object({ episodeIds: z.array(z.string().min(1)).min(1).max(500) }),
+]);
+
+/** DELETE — Sichtungen zurücknehmen, über watchIds oder episodeIds. */
+export const DELETE = withApi(async (request, user, context) => {
+  const { entryId } = await context.params;
+  if (!entryId) return apiError("Es fehlt die Kennung des Eintrags.", 400);
+
+  const body = await readJson(request, deleteSchema);
+
+  if ("watchIds" in body) {
+    await undoWatches(user.id, entryId, body.watchIds);
+  } else {
+    await unmarkEpisodes(user.id, entryId, body.episodeIds);
+  }
+  return { ok: true };
+});
diff --git a/src/app/api/v1/bibliothek/route.ts b/src/app/api/v1/bibliothek/route.ts
new file mode 100644
index 0000000..983d462
--- /dev/null
+++ b/src/app/api/v1/bibliothek/route.ts
@@ -0,0 +1,63 @@
+import { z } from "zod";
+import { readJson, readPaging, withApi } from "@/lib/api";
+import { getLibrary } from "@/lib/queries";
+import { addToLibrary } from "@/lib/library";
+import { ensureTitle } from "@/lib/catalog";
+import type { EntryStatus, TitleType } from "@/generated/prisma/client";
+
+const STATUSES = ["WATCHING", "PAUSED", "COMPLETED", "DROPPED", "WATCHLIST"] as const;
+
+/** GET /api/v1/bibliothek — Bibliothek lesen, mit denselben Filtern wie im UI. */
+export const GET = withApi(async (request, user) => {
+  const url = new URL(request.url);
+  const { limit, offset } = readPaging(request);
+
+  const status = url.searchParams.get("status");
+  const type = url.searchParams.get("typ");
+
+  const items = await getLibrary(user.id, {
+    query: url.searchParams.get("q") ?? undefined,
+    status: STATUSES.includes(status as EntryStatus) ? (status as EntryStatus) : undefined,
+    type: type === "SERIES" || type === "MOVIE" ? (type as TitleType) : undefined,
+    genre: url.searchParams.get("genre") ?? undefined,
+    tag: url.searchParams.get("tag") ?? undefined,
+    provider: url.searchParams.get("dienst") ?? undefined,
+  });
+
+  return {
+    total: items.length,
+    limit,
+    offset,
+    items: items.slice(offset, offset + limit),
+  };
+});
+
+const addSchema = z
+  .object({
+    titleId: z.string().min(1).optional(),
+    tmdbId: z.number().int().positive().optional(),
+    type: z.enum(["SERIES", "MOVIE"]).optional(),
+    status: z.enum(STATUSES).default("WATCHLIST"),
+  })
+  .refine((value) => Boolean(value.titleId) || Boolean(value.tmdbId && value.type), {
+    message: "Entweder titleId oder tmdbId zusammen mit type angeben.",
+  });
+
+/** POST /api/v1/bibliothek — Titel aufnehmen, per interner ID oder TMDB-ID. */
+export const POST = withApi(async (request, user) => {
+  const body = await readJson(request, addSchema);
+
+  let titleId = body.titleId;
+  if (!titleId && body.tmdbId && body.type) {
+    const title = await ensureTitle(body.type, body.tmdbId, { region: user.region });
+    titleId = title.id;
+  }
+  if (!titleId) {
+    throw new z.ZodError([
+      { code: "custom", path: ["titleId"], message: "Kein Titel angegeben." },
+    ]);
+  }
+
+  const entry = await addToLibrary(user.id, titleId, body.status);
+  return { id: entry.id, titleId: entry.titleId, status: entry.status };
+});
diff --git a/src/app/api/v1/export/route.ts b/src/app/api/v1/export/route.ts
new file mode 100644
index 0000000..d67ccc5
--- /dev/null
+++ b/src/app/api/v1/export/route.ts
@@ -0,0 +1,33 @@
+import { NextResponse } from "next/server";
+import { withApi } from "@/lib/api";
+import { exportCsv, exportJson } from "@/lib/transfer";
+
+/**
+ * GET /api/v1/export?format=json|csv
+ *
+ * Vollständiger Export der eigenen Daten. JSON enthält zusätzlich Sichtungen
+ * und Universen, CSV ist die schlanke Tabellenform für Tabellenkalkulationen.
+ */
+export const GET = withApi(async (request, user) => {
+  const url = new URL(request.url);
+  const format = url.searchParams.get("format") === "csv" ? "csv" : "json";
+  const stamp = new Date().toISOString().slice(0, 10);
+
+  if (format === "csv") {
+    const csv = await exportCsv(user.id);
+    return new NextResponse(csv, {
+      headers: {
+        "content-type": "text/csv; charset=utf-8",
+        "content-disposition": `attachment; filename="flimmer-${stamp}.csv"`,
+      },
+    });
+  }
+
+  const data = await exportJson(user.id);
+  return new NextResponse(JSON.stringify(data, null, 2), {
+    headers: {
+      "content-type": "application/json; charset=utf-8",
+      "content-disposition": `attachment; filename="flimmer-${stamp}.json"`,
+    },
+  });
+});
diff --git a/src/app/api/v1/kalender/route.ts b/src/app/api/v1/kalender/route.ts
new file mode 100644
index 0000000..cb9e47d
--- /dev/null
+++ b/src/app/api/v1/kalender/route.ts
@@ -0,0 +1,29 @@
+import { withApi } from "@/lib/api";
+import { getUpcomingEpisodes } from "@/lib/stats";
+
+/**
+ * GET /api/v1/kalender?von=2026-09-01&bis=2026-09-30
+ *
+ * Kommende Episoden der getrackten Serien. Ohne Angabe: die nächsten 30 Tage.
+ */
+export const GET = withApi(async (request, user) => {
+  const url = new URL(request.url);
+
+  const parse = (value: string | null, fallback: Date) => {
+    if (!value) return fallback;
+    const date = new Date(value);
+    return Number.isNaN(date.getTime()) ? fallback : date;
+  };
+
+  const from = parse(url.searchParams.get("von"), new Date());
+  const to = parse(url.searchParams.get("bis"), new Date(Date.now() + 30 * 86_400_000));
+
+  const episodes = await getUpcomingEpisodes(user.id, from, to);
+
+  return {
+    from: from.toISOString(),
+    to: to.toISOString(),
+    total: episodes.length,
+    items: episodes,
+  };
+});
diff --git a/src/app/api/v1/me/route.ts b/src/app/api/v1/me/route.ts
new file mode 100644
index 0000000..cdedadf
--- /dev/null
+++ b/src/app/api/v1/me/route.ts
@@ -0,0 +1,19 @@
+import { withApi } from "@/lib/api";
+import { prisma } from "@/lib/db";
+
+/** GET /api/v1/me — wer bin ich, und wie groß ist meine Bibliothek? */
+export const GET = withApi(async (_request, user) => {
+  const [entries, watches] = await Promise.all([
+    prisma.libraryEntry.count({ where: { userId: user.id, deletedAt: null } }),
+    prisma.watch.count({ where: { userId: user.id } }),
+  ]);
+
+  return {
+    id: user.id,
+    name: user.name,
+    email: user.email,
+    role: user.role,
+    region: user.region,
+    library: { entries, watches },
+  };
+});
diff --git a/src/app/api/v1/openapi.json/route.ts b/src/app/api/v1/openapi.json/route.ts
new file mode 100644
index 0000000..1a2ab4e
--- /dev/null
+++ b/src/app/api/v1/openapi.json/route.ts
@@ -0,0 +1,310 @@
+import { NextResponse } from "next/server";
+import { env } from "@/lib/env";
+import pkg from "../../../../../package.json";
+
+/**
+ * Maschinenlesbare Beschreibung der REST-API.
+ *
+ * Handgeschrieben statt aus Zod erzeugt: die Schnittstelle ist überschaubar,
+ * und ein Generator brächte eine weitere Abhängigkeit samt Versionsrhythmus
+ * für einen Nutzen, den ein Dutzend Zeilen JSON auch hergeben.
+ */
+export const dynamic = "force-dynamic";
+
+export function GET() {
+  const document = {
+    openapi: "3.1.0",
+    info: {
+      title: "Flimmer API",
+      version: pkg.version,
+      description:
+        "REST-Schnittstelle einer Flimmer-Instanz. Anmeldung über einen persönlichen " +
+        "API-Schlüssel (Einstellungen → API-Schlüssel) als Bearer-Token. Alle Antworten " +
+        "sind JSON; Zeitangaben in ISO 8601, Laufzeiten in Minuten.",
+      license: { name: "MIT" },
+    },
+    servers: [{ url: `${env.appUrl}/api/v1` }],
+    security: [{ bearerAuth: [] }],
+    components: {
+      securitySchemes: {
+        bearerAuth: { type: "http", scheme: "bearer", description: "Persönlicher API-Schlüssel" },
+      },
+      schemas: {
+        Fehler: {
+          type: "object",
+          properties: { error: { type: "string" }, details: {} },
+          required: ["error"],
+        },
+        Sichtungsergebnis: {
+          type: "object",
+          properties: {
+            watchIds: {
+              type: "array",
+              items: { type: "string" },
+              description: "Kennungen der neu angelegten Sichtungen — für DELETE zum Zurücknehmen.",
+            },
+            status: { type: "string" },
+            label: { type: "string" },
+          },
+        },
+      },
+    },
+    paths: {
+      "/me": {
+        get: {
+          summary: "Angemeldetes Konto",
+          responses: { "200": { description: "Konto samt Umfang der Bibliothek" } },
+        },
+      },
+      "/bibliothek": {
+        get: {
+          summary: "Bibliothek lesen",
+          parameters: [
+            { name: "q", in: "query", schema: { type: "string" }, description: "Volltextsuche" },
+            {
+              name: "status",
+              in: "query",
+              schema: {
+                type: "string",
+                enum: ["WATCHING", "PAUSED", "COMPLETED", "DROPPED", "WATCHLIST"],
+              },
+            },
+            { name: "typ", in: "query", schema: { type: "string", enum: ["SERIES", "MOVIE"] } },
+            { name: "genre", in: "query", schema: { type: "string" } },
+            { name: "tag", in: "query", schema: { type: "string" } },
+            { name: "dienst", in: "query", schema: { type: "string" } },
+            { name: "limit", in: "query", schema: { type: "integer", default: 50, maximum: 200 } },
+            { name: "offset", in: "query", schema: { type: "integer", default: 0 } },
+          ],
+          responses: { "200": { description: "Einträge mit Fortschritt" } },
+        },
+        post: {
+          summary: "Titel aufnehmen",
+          requestBody: {
+            required: true,
+            content: {
+              "application/json": {
+                schema: {
+                  type: "object",
+                  properties: {
+                    titleId: { type: "string", description: "Interne Kennung" },
+                    tmdbId: { type: "integer", description: "Alternativ: TMDB-Kennung" },
+                    type: { type: "string", enum: ["SERIES", "MOVIE"] },
+                    status: {
+                      type: "string",
+                      enum: ["WATCHING", "PAUSED", "COMPLETED", "DROPPED", "WATCHLIST"],
+                      default: "WATCHLIST",
+                    },
+                  },
+                },
+              },
+            },
+          },
+          responses: { "200": { description: "Angelegter oder vorhandener Eintrag" } },
+        },
+      },
+      "/bibliothek/{entryId}": {
+        parameters: [{ name: "entryId", in: "path", required: true, schema: { type: "string" } }],
+        get: { summary: "Eintrag mit Fortschritt", responses: { "200": { description: "Eintrag" } } },
+        patch: {
+          summary: "Status, Bewertung, Notiz ändern",
+          requestBody: {
+            required: true,
+            content: {
+              "application/json": {
+                schema: {
+                  type: "object",
+                  properties: {
+                    status: {
+                      type: "string",
+                      enum: ["WATCHING", "PAUSED", "COMPLETED", "DROPPED", "WATCHLIST"],
+                    },
+                    rating: { type: "integer", minimum: 1, maximum: 10, nullable: true },
+                    notes: { type: "string", nullable: true },
+                    whereToWatch: { type: "string", nullable: true },
+                    favorite: { type: "boolean" },
+                  },
+                },
+              },
+            },
+          },
+          responses: { "200": { description: "Gespeichert" } },
+        },
+        delete: {
+          summary: "In den Papierkorb legen",
+          responses: { "200": { description: "Verschoben" } },
+        },
+      },
+      "/bibliothek/{entryId}/sichtungen": {
+        parameters: [{ name: "entryId", in: "path", required: true, schema: { type: "string" } }],
+        get: { summary: "Sichtungen auflisten", responses: { "200": { description: "Sichtungen" } } },
+        post: {
+          summary: "Als gesehen markieren",
+          description:
+            "action=next hakt die nächste offene Episode ab, movie einen Film, " +
+            "episodes eine Auswahl, season eine ganze Staffel, upTo alles bis zur genannten Episode.",
+          requestBody: {
+            required: true,
+            content: {
+              "application/json": {
+                schema: {
+                  oneOf: [
+                    {
+                      type: "object",
+                      properties: { action: { const: "next" } },
+                      required: ["action"],
+                    },
+                    {
+                      type: "object",
+                      properties: { action: { const: "movie" } },
+                      required: ["action"],
+                    },
+                    {
+                      type: "object",
+                      properties: {
+                        action: { const: "episodes" },
+                        episodeIds: { type: "array", items: { type: "string" } },
+                      },
+                      required: ["action", "episodeIds"],
+                    },
+                    {
+                      type: "object",
+                      properties: { action: { const: "season" }, seasonId: { type: "string" } },
+                      required: ["action", "seasonId"],
+                    },
+                    {
+                      type: "object",
+                      properties: { action: { const: "upTo" }, episodeId: { type: "string" } },
+                      required: ["action", "episodeId"],
+                    },
+                  ],
+                },
+              },
+            },
+          },
+          responses: {
+            "200": {
+              description: "Angelegte Sichtungen",
+              content: {
+                "application/json": {
+                  schema: { $ref: "#/components/schemas/Sichtungsergebnis" },
+                },
+              },
+            },
+          },
+        },
+        delete: {
+          summary: "Sichtungen zurücknehmen",
+          requestBody: {
+            required: true,
+            content: {
+              "application/json": {
+                schema: {
+                  oneOf: [
+                    {
+                      type: "object",
+                      properties: { watchIds: { type: "array", items: { type: "string" } } },
+                      required: ["watchIds"],
+                    },
+                    {
+                      type: "object",
+                      properties: { episodeIds: { type: "array", items: { type: "string" } } },
+                      required: ["episodeIds"],
+                    },
+                  ],
+                },
+              },
+            },
+          },
+          responses: { "200": { description: "Zurückgenommen" } },
+        },
+      },
+      "/suche": {
+        get: {
+          summary: "TMDB durchsuchen",
+          parameters: [
+            { name: "q", in: "query", required: true, schema: { type: "string", minLength: 2 } },
+            { name: "typ", in: "query", schema: { type: "string", enum: ["serie", "film"] } },
+          ],
+          responses: {
+            "200": { description: "Treffer mit TMDB-Kennung" },
+            "503": { description: "Kein TMDB-Schlüssel hinterlegt" },
+          },
+        },
+      },
+      "/kalender": {
+        get: {
+          summary: "Kommende Episoden",
+          parameters: [
+            { name: "von", in: "query", schema: { type: "string", format: "date" } },
+            { name: "bis", in: "query", schema: { type: "string", format: "date" } },
+          ],
+          responses: { "200": { description: "Termine im Zeitraum" } },
+        },
+      },
+      "/statistik": {
+        get: {
+          summary: "Kennzahlen und Verteilungen",
+          parameters: [{ name: "jahr", in: "query", schema: { type: "integer" } }],
+          responses: { "200": { description: "Statistik" } },
+        },
+      },
+      "/universen": {
+        get: { summary: "Universen auflisten", responses: { "200": { description: "Universen" } } },
+        post: {
+          summary: "Universum anlegen",
+          requestBody: {
+            required: true,
+            content: {
+              "application/json": {
+                schema: {
+                  type: "object",
+                  properties: { name: { type: "string" }, description: { type: "string" } },
+                  required: ["name"],
+                },
+              },
+            },
+          },
+          responses: { "200": { description: "Angelegt" } },
+        },
+      },
+      "/universen/{id}": {
+        parameters: [{ name: "id", in: "path", required: true, schema: { type: "string" } }],
+        get: {
+          summary: "Universum mit Reihenfolge und Fortschritt",
+          parameters: [{ name: "reihenfolge", in: "query", schema: { type: "string" } }],
+          responses: { "200": { description: "Universum" }, "404": { description: "Unbekannt" } },
+        },
+        post: {
+          summary: "Titel ins Universum aufnehmen",
+          requestBody: {
+            required: true,
+            content: {
+              "application/json": {
+                schema: {
+                  type: "object",
+                  properties: { titleId: { type: "string" } },
+                  required: ["titleId"],
+                },
+              },
+            },
+          },
+          responses: { "200": { description: "Aufgenommen" } },
+        },
+      },
+      "/export": {
+        get: {
+          summary: "Eigene Daten exportieren",
+          parameters: [
+            { name: "format", in: "query", schema: { type: "string", enum: ["json", "csv"] } },
+          ],
+          responses: { "200": { description: "Datei" } },
+        },
+      },
+    },
+  };
+
+  return NextResponse.json(document, {
+    headers: { "cache-control": "public, max-age=300" },
+  });
+}
diff --git a/src/app/api/v1/statistik/route.ts b/src/app/api/v1/statistik/route.ts
new file mode 100644
index 0000000..9ee0dd9
--- /dev/null
+++ b/src/app/api/v1/statistik/route.ts
@@ -0,0 +1,25 @@
+import { withApi } from "@/lib/api";
+import {
+  getGenreDistribution,
+  getMonthlyActivity,
+  getProviderDistribution,
+  getTotals,
+  getYearReview,
+} from "@/lib/stats";
+
+/** GET /api/v1/statistik?jahr=2026 — alle Kennzahlen auf einmal. */
+export const GET = withApi(async (request, user) => {
+  const url = new URL(request.url);
+  const parsed = Number.parseInt(url.searchParams.get("jahr") ?? "", 10);
+  const year = Number.isFinite(parsed) ? parsed : new Date().getFullYear();
+
+  const [totals, monthly, providers, genres, review] = await Promise.all([
+    getTotals(user.id),
+    getMonthlyActivity(user.id, 12),
+    getProviderDistribution(user.id),
+    getGenreDistribution(user.id),
+    getYearReview(user.id, year),
+  ]);
+
+  return { totals, monthly, providers, genres, yearReview: review };
+});
diff --git a/src/app/api/v1/suche/route.ts b/src/app/api/v1/suche/route.ts
new file mode 100644
index 0000000..22a8dd3
--- /dev/null
+++ b/src/app/api/v1/suche/route.ts
@@ -0,0 +1,53 @@
+import { apiError, withApi } from "@/lib/api";
+import { env } from "@/lib/env";
+import { searchMovies, searchMulti, searchSeries, TmdbNotConfiguredError } from "@/lib/tmdb";
+
+/**
+ * GET /api/v1/suche?q=…&typ=serie|film
+ *
+ * Durchsucht TMDB. Die Treffer tragen die TMDB-ID — damit lässt sich der
+ * Titel über POST /api/v1/bibliothek direkt aufnehmen.
+ */
+export const GET = withApi(async (request) => {
+  const url = new URL(request.url);
+  const query = (url.searchParams.get("q") ?? "").trim();
+  const type = url.searchParams.get("typ");
+
+  if (query.length < 2) {
+    return apiError("Der Suchbegriff braucht mindestens zwei Zeichen.", 400);
+  }
+  if (!env.tmdb.isConfigured) {
+    return apiError("Auf dieser Instanz ist kein TMDB-Schlüssel hinterlegt.", 503);
+  }
+
+  try {
+    const data =
+      type === "serie"
+        ? await searchSeries(query)
+        : type === "film"
+          ? await searchMovies(query)
+          : await searchMulti(query);
+
+    return {
+      query,
+      total: data.total_results,
+      items: data.results.map((item) => {
+        const isSeries =
+          item.media_type === "tv" || (type === "serie" && item.media_type === undefined);
+        const date = isSeries ? item.first_air_date : item.release_date;
+        return {
+          tmdbId: item.id,
+          type: isSeries ? "SERIES" : "MOVIE",
+          title: item.name ?? item.title ?? "Ohne Titel",
+          overview: item.overview ?? null,
+          posterPath: item.poster_path ?? null,
+          year: date ? Number.parseInt(date.slice(0, 4), 10) : null,
+          voteAverage: item.vote_average ?? null,
+        };
+      }),
+    };
+  } catch (error) {
+    if (error instanceof TmdbNotConfiguredError) return apiError(error.message, 503);
+    return apiError(error instanceof Error ? error.message : "Die Suche ist fehlgeschlagen.", 502);
+  }
+});
diff --git a/src/app/api/v1/universen/[id]/route.ts b/src/app/api/v1/universen/[id]/route.ts
new file mode 100644
index 0000000..f670157
--- /dev/null
+++ b/src/app/api/v1/universen/[id]/route.ts
@@ -0,0 +1,27 @@
+import { z } from "zod";
+import { apiError, readJson, withApi } from "@/lib/api";
+import { addTitle, getUniverse } from "@/lib/universes";
+
+/** GET /api/v1/universen/{id}?reihenfolge=… — Inhalt und Fortschritt. */
+export const GET = withApi(async (request, user, context) => {
+  const { id } = await context.params;
+  if (!id) return apiError("Es fehlt die Kennung des Universums.", 400);
+
+  const url = new URL(request.url);
+  const universe = await getUniverse(user.id, id, url.searchParams.get("reihenfolge") ?? undefined);
+  if (!universe) return apiError("Dieses Universum gibt es nicht.", 404);
+
+  return universe;
+});
+
+const addSchema = z.object({ titleId: z.string().min(1) });
+
+/** POST /api/v1/universen/{id} — Titel aufnehmen. */
+export const POST = withApi(async (request, user, context) => {
+  const { id } = await context.params;
+  if (!id) return apiError("Es fehlt die Kennung des Universums.", 400);
+
+  const body = await readJson(request, addSchema);
+  await addTitle(user.id, id, body.titleId);
+  return { ok: true };
+});
diff --git a/src/app/api/v1/universen/route.ts b/src/app/api/v1/universen/route.ts
new file mode 100644
index 0000000..879dc65
--- /dev/null
+++ b/src/app/api/v1/universen/route.ts
@@ -0,0 +1,21 @@
+import { z } from "zod";
+import { readJson, withApi } from "@/lib/api";
+import { createUniverse, listUniverses } from "@/lib/universes";
+
+/** GET /api/v1/universen — eigene und geteilte Universen. */
+export const GET = withApi(async (_request, user) => {
+  const universes = await listUniverses(user.id);
+  return { total: universes.length, items: universes };
+});
+
+const createSchema = z.object({
+  name: z.string().trim().min(1).max(120),
+  description: z.string().max(2000).optional(),
+});
+
+/** POST /api/v1/universen — neues Universum anlegen. */
+export const POST = withApi(async (request, user) => {
+  const body = await readJson(request, createSchema);
+  const universe = await createUniverse(user.id, body.name, body.description);
+  return { id: universe.id, name: universe.name, slug: universe.slug };
+});
diff --git a/src/lib/api.ts b/src/lib/api.ts
new file mode 100644
index 0000000..d3efcfb
--- /dev/null
+++ b/src/lib/api.ts
@@ -0,0 +1,89 @@
+import "server-only";
+import { NextResponse } from "next/server";
+import { z } from "zod";
+import { getApiUser, type SessionUser } from "./auth";
+import { LibraryError } from "./library";
+import { UniverseError } from "./universes";
+
+/**
+ * Gemeinsames Gerüst der REST-API.
+ *
+ * Zwei Dinge macht jeder Endpunkt gleich: die Anmeldung prüfen (Bearer-Token
+ * oder Sitzungscookie — dieselben Endpunkte bedienen Skripte und das eigene
+ * Frontend) und Fehler in eine einheitliche Form bringen.
+ */
+
+export type ApiHandler<T = unknown> = (
+  request: Request,
+  user: SessionUser,
+  context: { params: Promise<Record<string, string>> },
+) => Promise<T>;
+
+export function apiError(message: string, status = 400, details?: unknown) {
+  return NextResponse.json({ error: message, ...(details ? { details } : {}) }, { status });
+}
+
+/**
+ * Umhüllt einen Endpunkt: Anmeldung, Fehlerbehandlung, JSON-Antwort.
+ * Gibt der Handler bereits eine Response zurück, wird sie durchgereicht.
+ */
+export function withApi<T>(handler: ApiHandler<T>) {
+  return async (request: Request, context: { params: Promise<Record<string, string>> }) => {
+    const user = await getApiUser(request);
+    if (!user) {
+      return NextResponse.json(
+        {
+          error:
+            "Nicht angemeldet. Schicke einen API-Schlüssel im Kopf: Authorization: Bearer <schlüssel>",
+        },
+        { status: 401, headers: { "www-authenticate": "Bearer" } },
+      );
+    }
+
+    try {
+      const result = await handler(request, user, context);
+      if (result instanceof NextResponse) return result;
+      return NextResponse.json(result ?? { ok: true });
+    } catch (error) {
+      if (error instanceof z.ZodError) {
+        return apiError("Die Anfrage ist unvollständig oder falsch aufgebaut.", 422, error.issues);
+      }
+      if (error instanceof LibraryError || error instanceof UniverseError) {
+        return apiError(error.message, 400);
+      }
+      console.error("API-Fehler:", error);
+      return apiError("Interner Fehler.", 500);
+    }
+  };
+}
+
+/** Liest und prüft den JSON-Rumpf einer Anfrage. */
+export async function readJson<S extends z.ZodTypeAny>(
+  request: Request,
+  schema: S,
+): Promise<z.infer<S>> {
+  let raw: unknown;
+  try {
+    raw = await request.json();
+  } catch {
+    throw new z.ZodError([
+      {
+        code: "custom",
+        path: [],
+        message: "Der Rumpf der Anfrage ist kein gültiges JSON.",
+      },
+    ]);
+  }
+  return schema.parse(raw);
+}
+
+/** Seitenweise Abfrage: `?limit=50&offset=0` */
+export function readPaging(request: Request, defaultLimit = 50, maxLimit = 200) {
+  const url = new URL(request.url);
+  const limit = Math.min(
+    maxLimit,
+    Math.max(1, Number.parseInt(url.searchParams.get("limit") ?? "", 10) || defaultLimit),
+  );
+  const offset = Math.max(0, Number.parseInt(url.searchParams.get("offset") ?? "", 10) || 0);
+  return { limit, offset };
+}