diff --git a/AGENTS.md b/AGENTS.md
index 93344dc..cd9129f 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -13,16 +13,18 @@ Tibi CMS starter template — Svelte 5 SPA with esbuild, SSR via goja, and Playw
 ## Setup commands
 
 - Install deps: `yarn install`
-- Start dev (Docker): `make docker-up && make docker-start`
-- Start dev (local): `yarn dev`
+- Start dev: `make docker-up && make docker-start`
+- Start with mock data: set `MOCK=1` in `.env`, then `make docker-up && make docker-start`
 - Build frontend: `yarn build`
 - Build SSR bundle: `yarn build:server`
 - Validate types: `yarn validate`
 
 ## Development workflow
 
-- Default dev flow is Docker/Makefile: `make docker-up`, `make docker-start`, `make docker-logs`, `make docker-restart-frontend`.
-- Local dev is secondary: `yarn dev` for watch, `yarn build` and `yarn build:server` for production builds.
+- **Dev servers always run in Docker** — never use `yarn dev` or `yarn start` locally; web access only works through the Docker reverse proxy.
+- Docker/Makefile commands: `make docker-up`, `make docker-start`, `make docker-logs`, `make docker-restart-frontend`.
+- Local `yarn` is only for standalone tasks: `yarn build`, `yarn build:server`, `yarn validate`.
+- **Mock mode**: Set `MOCK=1` to run the frontend without a tibi-server. API calls are served from JSON files in `frontend/mocking/`. Enable in Docker via `MOCK=1` in `.env`, then `make docker-up && make docker-start`. Missing mock endpoints return 404.
 - Frontend code is automatically built by watcher and BrowserSync; backend hooks are automatically reloaded on change.
 - Read `.env` for environment URLs and secrets.
 - `webserver/` is for staging/ops only; use BrowserSync/esbuild for day-to-day dev.
diff --git a/docker-compose-local.yml b/docker-compose-local.yml
index 5ef9331..5e3070c 100644
--- a/docker-compose-local.yml
+++ b/docker-compose-local.yml
@@ -14,6 +14,8 @@ services:
             - ./tmp/.yarn:/.yarn
         working_dir: /data
         command: sh -c "yarn install && API_BASE=http://tibiserver:8080/api/v1/_/${TIBI_NAMESPACE} yarn start${START_SCRIPT}"
+        environment:
+            MOCK: ${MOCK:-0}
         expose:
             - 3000
         labels:
diff --git a/esbuild.config.js b/esbuild.config.js
index 7ec063f..accb2d5 100644
--- a/esbuild.config.js
+++ b/esbuild.config.js
@@ -44,6 +44,25 @@ const resolvePlugin = {
     },
 }
 
+// When MOCK is disabled, replace the mock module with a no-op stub so
+// esbuild can tree-shake all mock data out of the production bundle.
+const mockPlugin = {
+    name: "mockPlugin",
+    setup(build) {
+        if (process.env.MOCK !== "1") {
+            build.onResolve({ filter: /\/mock$/ }, (args) => {
+                if (args.importer.includes("api.ts") || args.importer.includes("api.js")) {
+                    return { path: "mock-noop", namespace: "mock-noop" }
+                }
+            })
+            build.onLoad({ filter: /.*/, namespace: "mock-noop" }, () => ({
+                contents: "export function mockApiRequest() { return null }",
+                loader: "ts",
+            }))
+        }
+    },
+}
+
 ////////////////////////// esbuild-svelte
 
 const sveltePlugin = require("esbuild-svelte")
@@ -84,7 +103,10 @@ const options = {
     minify: process.argv[2] == "build",
     bundle: true,
     splitting: false,
-    plugins: [esbuildSvelte, postcssPlugin(), resolvePlugin],
+    define: {
+        __MOCK__: process.env.MOCK === "1" ? "true" : "false",
+    },
+    plugins: [esbuildSvelte, postcssPlugin(), resolvePlugin, mockPlugin],
     loader: {
         ".woff2": "file",
         ".woff": "file",
diff --git a/frontend/mocking/content.json b/frontend/mocking/content.json
new file mode 100644
index 0000000..813386f
--- /dev/null
+++ b/frontend/mocking/content.json
@@ -0,0 +1,76 @@
+[
+    {
+        "id": "home",
+        "_id": "home",
+        "active": true,
+        "type": "page",
+        "lang": "de",
+        "translationKey": "home",
+        "name": "Startseite",
+        "path": "/",
+        "blocks": [
+            {
+                "type": "hero",
+                "headline": "Willkommen",
+                "headlineH1": true,
+                "subline": "Demo-Startseite des Starter-Templates",
+                "heroImage": {
+                    "image": "demo-hero"
+                }
+            },
+            {
+                "type": "richtext",
+                "headline": "Über uns",
+                "text": "<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit.</p>"
+            }
+        ],
+        "meta": {
+            "title": "Startseite",
+            "description": "Demo-Startseite"
+        }
+    },
+    {
+        "id": "about",
+        "_id": "about",
+        "active": true,
+        "type": "page",
+        "lang": "de",
+        "translationKey": "about",
+        "name": "Über uns",
+        "path": "/ueber-uns",
+        "blocks": [
+            {
+                "type": "richtext",
+                "headline": "Über uns",
+                "headlineH1": true,
+                "text": "<p>Wir sind ein Demo-Unternehmen.</p>"
+            }
+        ],
+        "meta": {
+            "title": "Über uns",
+            "description": "Erfahren Sie mehr über uns"
+        }
+    },
+    {
+        "id": "contact",
+        "_id": "contact",
+        "active": true,
+        "type": "page",
+        "lang": "de",
+        "translationKey": "contact",
+        "name": "Kontakt",
+        "path": "/kontakt",
+        "blocks": [
+            {
+                "type": "richtext",
+                "headline": "Kontakt",
+                "headlineH1": true,
+                "text": "<p>Schreiben Sie uns eine Nachricht.</p>"
+            }
+        ],
+        "meta": {
+            "title": "Kontakt",
+            "description": "Kontaktieren Sie uns"
+        }
+    }
+]
\ No newline at end of file
diff --git a/frontend/mocking/navigation.json b/frontend/mocking/navigation.json
new file mode 100644
index 0000000..a06c97b
--- /dev/null
+++ b/frontend/mocking/navigation.json
@@ -0,0 +1,38 @@
+[
+    {
+        "id": "header-de",
+        "_id": "header-de",
+        "language": "de",
+        "type": "header",
+        "elements": [
+            {
+                "name": "Startseite",
+                "page": "home"
+            },
+            {
+                "name": "Über uns",
+                "page": "about"
+            },
+            {
+                "name": "Kontakt",
+                "page": "contact"
+            }
+        ]
+    },
+    {
+        "id": "footer-de",
+        "_id": "footer-de",
+        "language": "de",
+        "type": "footer",
+        "elements": [
+            {
+                "name": "Impressum",
+                "page": "imprint"
+            },
+            {
+                "name": "Datenschutz",
+                "page": "privacy"
+            }
+        ]
+    }
+]
\ No newline at end of file
diff --git a/frontend/src/lib/api.ts b/frontend/src/lib/api.ts
index d2c9bcb..2a289ec 100644
--- a/frontend/src/lib/api.ts
+++ b/frontend/src/lib/api.ts
@@ -16,6 +16,7 @@ import { apiBaseOverride } from "./store"
 import { incrementRequests, decrementRequests } from "./requestsStore"
 import { setServerBuildTime } from "./serverBuildInfo"
 import { checkBuildVersion } from "./versionCheck"
+import { mockApiRequest } from "./mock"
 
 // ---------------------------------------------------------------------------
 // Request deduplication
@@ -84,6 +85,14 @@ export const api = async <T>(
             }
             incrementRequests()
 
+            // ── Mock interceptor (tree-shaken when __MOCK__ is false) ──
+            if (__MOCK__) {
+                const mockResult = mockApiRequest(endpoint, mergedOptions, body)
+                if (mockResult) return mockResult as ApiResult<T>
+                // No mock data for this endpoint → 404
+                throw { response: { status: 404 }, data: { error: `[mock] No mock data for "${endpoint}"` } }
+            }
+
             const data = await apiRequest(_apiBaseOverride + endpoint, mergedOptions, body, sentry)
 
             // Build-version check only on GETs (don't reload mid-write)
diff --git a/frontend/src/lib/mock.ts b/frontend/src/lib/mock.ts
new file mode 100644
index 0000000..38534cd
--- /dev/null
+++ b/frontend/src/lib/mock.ts
@@ -0,0 +1,252 @@
+/**
+ * API Mock Interceptor
+ *
+ * Serves mock data from `frontend/mocking/<endpoint>.json` when `__MOCK__` is enabled.
+ * Supports tibi-server-style filtering, single-item retrieval by ID, sorting,
+ * limit/offset pagination, and projection.
+ *
+ * Activate via build flag: `MOCK=1 yarn start`
+ * For production builds, the entire module is eliminated by dead-code removal.
+ */
+
+// ---------------------------------------------------------------------------
+// Mock data registry — static imports for tree-shaking compatibility.
+// Add new collections here as needed.
+// ---------------------------------------------------------------------------
+import contentData from "../../mocking/content.json"
+import navigationData from "../../mocking/navigation.json"
+
+const mockRegistry: Record<string, Record<string, unknown>[]> = {
+    content: contentData as Record<string, unknown>[],
+    navigation: navigationData as Record<string, unknown>[],
+}
+
+// ---------------------------------------------------------------------------
+// Public API
+// ---------------------------------------------------------------------------
+
+/**
+ * Attempt to serve the request from mock data.
+ * Returns an `ApiResult`-shaped object or `null` if no mock data is registered.
+ *
+ * @param endpoint  Raw endpoint string, e.g. `"content"` or `"content/home"`
+ * @param options   ApiOptions (filter, sort, limit, offset, projection)
+ */
+export function mockApiRequest(endpoint: string, options?: ApiOptions, _body?: unknown): ApiResult<unknown> | null {
+    // Strip leading `/api/` or `/` if present (callers may include it)
+    const cleaned = endpoint.replace(/^\/?(api\/)?/, "")
+
+    // Split into collection name and optional ID: "content/home" → ["content", "home"]
+    const segments = cleaned.split("/").filter(Boolean)
+    const collection = segments[0]
+    const itemId = segments[1] // undefined for list requests
+
+    const sourceData = mockRegistry[collection]
+    if (!sourceData) return null // no mock registered → interceptor should 404
+
+    console.log(`[mock] ${itemId ? "GET" : "LIST"} /${collection}${itemId ? "/" + itemId : ""}`, options?.filter ?? "")
+
+    // --- Single-item retrieval ---
+    if (itemId) {
+        const item = sourceData.find((e) => e.id === itemId || e._id === itemId)
+        return {
+            data: item ?? null,
+            count: item ? 1 : 0,
+            buildTime: null,
+        }
+    }
+
+    // --- List retrieval with filter / sort / pagination ---
+    let results = [...sourceData]
+
+    // Filter
+    if (options?.filter) {
+        results = results.filter((entry) => matchesFilter(entry, options.filter!))
+    }
+
+    const totalCount = results.length
+
+    // Sort
+    if (options?.sort) {
+        results = applySort(results, options.sort)
+    }
+
+    // Pagination
+    if (options?.offset) {
+        results = results.slice(options.offset)
+    }
+    if (options?.limit) {
+        results = results.slice(0, options.limit)
+    }
+
+    // Projection
+    if (options?.projection) {
+        results = applyProjection(results, options.projection)
+    }
+
+    return {
+        data: results,
+        count: totalCount,
+        buildTime: null,
+    }
+}
+
+// ---------------------------------------------------------------------------
+// Filter engine — simple MongoDB-style matching
+// ---------------------------------------------------------------------------
+
+function matchesFilter(entry: Record<string, unknown>, filter: MongoFilter): boolean {
+    for (const key of Object.keys(filter)) {
+        const condition = filter[key]
+
+        // Logical operators
+        if (key === "$and") {
+            if (!Array.isArray(condition)) return false
+            return condition.every((sub: MongoFilter) => matchesFilter(entry, sub))
+        }
+        if (key === "$or") {
+            if (!Array.isArray(condition)) return false
+            return condition.some((sub: MongoFilter) => matchesFilter(entry, sub))
+        }
+        if (key === "$nor") {
+            if (!Array.isArray(condition)) return false
+            return !condition.some((sub: MongoFilter) => matchesFilter(entry, sub))
+        }
+
+        const value = getNestedValue(entry, key)
+
+        // Operator object: { field: { $in: [...], $ne: "x", ... } }
+        if (condition !== null && typeof condition === "object" && !Array.isArray(condition)) {
+            if (!matchesOperators(value, condition as Record<string, unknown>)) return false
+            continue
+        }
+
+        // Direct equality (or array-contains)
+        if (Array.isArray(value)) {
+            if (!value.includes(condition)) return false
+        } else {
+            if (value !== condition) return false
+        }
+    }
+    return true
+}
+
+function matchesOperators(value: unknown, operators: Record<string, unknown>): boolean {
+    for (const op of Object.keys(operators)) {
+        const expected = operators[op]
+        switch (op) {
+            case "$eq":
+                if (value !== expected) return false
+                break
+            case "$ne":
+                if (value === expected) return false
+                break
+            case "$in":
+                if (!Array.isArray(expected) || !expected.includes(value)) return false
+                break
+            case "$nin":
+                if (Array.isArray(expected) && expected.includes(value)) return false
+                break
+            case "$exists":
+                if (expected ? value === undefined : value !== undefined) return false
+                break
+            case "$gt":
+                if (typeof value !== "number" || typeof expected !== "number" || value <= expected) return false
+                break
+            case "$gte":
+                if (typeof value !== "number" || typeof expected !== "number" || value < expected) return false
+                break
+            case "$lt":
+                if (typeof value !== "number" || typeof expected !== "number" || value >= expected) return false
+                break
+            case "$lte":
+                if (typeof value !== "number" || typeof expected !== "number" || value > expected) return false
+                break
+            case "$regex": {
+                const flags = (operators.$options as string) || ""
+                const re = new RegExp(expected as string, flags)
+                if (typeof value !== "string" || !re.test(value)) return false
+                break
+            }
+            default:
+                // Unknown operator — skip gracefully
+                break
+        }
+    }
+    return true
+}
+
+/** Resolve dot-notation paths: `"meta.title"` → `entry.meta.title` */
+function getNestedValue(obj: Record<string, unknown>, path: string): unknown {
+    return path.split(".").reduce<unknown>((acc, part) => {
+        if (acc !== null && typeof acc === "object") return (acc as Record<string, unknown>)[part]
+        return undefined
+    }, obj)
+}
+
+// ---------------------------------------------------------------------------
+// Sort
+// ---------------------------------------------------------------------------
+
+function applySort(data: Record<string, unknown>[], sortSpec: string): Record<string, unknown>[] {
+    // tibi-server sort format: "field" (asc) or "-field" (desc), comma-separated
+    const fields = sortSpec
+        .split(",")
+        .map((s) => s.trim())
+        .filter(Boolean)
+
+    return [...data].sort((a, b) => {
+        for (const field of fields) {
+            const desc = field.startsWith("-")
+            const key = desc ? field.slice(1) : field
+            const aVal = getNestedValue(a, key)
+            const bVal = getNestedValue(b, key)
+            const cmp = compareValues(aVal, bVal)
+            if (cmp !== 0) return desc ? -cmp : cmp
+        }
+        return 0
+    })
+}
+
+function compareValues(a: unknown, b: unknown): number {
+    if (a === b) return 0
+    if (a === undefined || a === null) return -1
+    if (b === undefined || b === null) return 1
+    if (typeof a === "number" && typeof b === "number") return a - b
+    return String(a).localeCompare(String(b))
+}
+
+// ---------------------------------------------------------------------------
+// Projection
+// ---------------------------------------------------------------------------
+
+function applyProjection(data: Record<string, unknown>[], projectionStr: string): Record<string, unknown>[] {
+    // projection format: "field1,field2" (include) or "-field1,-field2" (exclude)
+    const fields = projectionStr
+        .split(",")
+        .map((s) => s.trim())
+        .filter(Boolean)
+    if (fields.length === 0) return data
+
+    const isExclude = fields[0].startsWith("-")
+
+    return data.map((entry) => {
+        if (isExclude) {
+            const exclude = new Set(fields.map((f) => f.replace(/^-/, "")))
+            const result: Record<string, unknown> = {}
+            for (const key of Object.keys(entry)) {
+                if (!exclude.has(key)) result[key] = entry[key]
+            }
+            return result
+        } else {
+            const result: Record<string, unknown> = {}
+            for (const field of fields) {
+                if (field in entry) result[field] = entry[field]
+            }
+            // Always include id/_id
+            if (entry.id !== undefined) result.id = entry.id
+            if (entry._id !== undefined) result._id = entry._id
+            return result
+        }
+    })
+}
diff --git a/package.json b/package.json
index e521a21..cb9ed8f 100644
--- a/package.json
+++ b/package.json
@@ -9,6 +9,7 @@
         "validate": "svelte-check && tsc --noEmit",
         "dev": "node scripts/esbuild-wrapper.js watch",
         "start": "node scripts/esbuild-wrapper.js start",
+        "start:mock": "MOCK=1 node scripts/esbuild-wrapper.js start",
         "start:ssr": "SSR=1 node scripts/esbuild-wrapper.js start",
         "build": "node scripts/esbuild-wrapper.js build",
         "build:admin": "node scripts/esbuild-wrapper.js build esbuild.config.admin.js",
diff --git a/types/global.d.ts b/types/global.d.ts
index 6cc0945..4340a64 100644
--- a/types/global.d.ts
+++ b/types/global.d.ts
@@ -155,3 +155,6 @@ interface ProductEntry {
     id: string
     // ...
 }
+
+/** Build-time flag: `true` when built with `MOCK=1`, enables API mock interceptor */
+declare const __MOCK__: boolean