diff --git a/packages/fastify-core/package.json b/packages/fastify-core/package.json
index 185e2eb3..8c65a571 100644
--- a/packages/fastify-core/package.json
+++ b/packages/fastify-core/package.json
@@ -21,7 +21,21 @@
     "@bytelyst/errors": "workspace:*"
   },
   "peerDependencies": {
+    "@fastify/cors": ">=10.0.0",
+    "@fastify/swagger": ">=9.0.0",
     "fastify": ">=5.0.0",
-    "@fastify/cors": ">=10.0.0"
+    "fastify-metrics": ">=10.0.0"
+  },
+  "peerDependenciesMeta": {
+    "@fastify/swagger": {
+      "optional": true
+    },
+    "fastify-metrics": {
+      "optional": true
+    }
+  },
+  "devDependencies": {
+    "@fastify/swagger": "^9.7.0",
+    "fastify-metrics": "^10.6.0"
   }
 }
diff --git a/packages/fastify-core/src/create-app.ts b/packages/fastify-core/src/create-app.ts
index 4b462125..9c947446 100644
--- a/packages/fastify-core/src/create-app.ts
+++ b/packages/fastify-core/src/create-app.ts
@@ -26,7 +26,7 @@ import type { ServiceAppOptions, FastifyApp } from './types.js';
  * ```
  */
 export async function createServiceApp(options: ServiceAppOptions): Promise<FastifyApp> {
-  const { name, version, description, corsOrigin, logger = true } = options;
+  const { name, version, description, corsOrigin, logger = true, swagger, metrics } = options;
 
   const app = Fastify({ logger });
 
@@ -34,6 +34,28 @@ export async function createServiceApp(options: ServiceAppOptions): Promise<Fast
   const origin = corsOrigin ? corsOrigin.split(',').map(o => o.trim()) : true;
   await app.register(cors, { origin });
 
+  // OpenAPI spec (optional — consumer must have @fastify/swagger installed)
+  if (swagger) {
+    const swaggerPlugin = (await import('@fastify/swagger')).default;
+    await app.register(swaggerPlugin, {
+      openapi: {
+        info: {
+          title: swagger.title,
+          version,
+          ...(swagger.description && { description: swagger.description }),
+        },
+        ...(swagger.port && { servers: [{ url: `http://localhost:${swagger.port}` }] }),
+      },
+    });
+  }
+
+  // Prometheus metrics (optional — consumer must have fastify-metrics installed)
+  if (metrics) {
+    const metricsMod = await import('fastify-metrics');
+    const plugin = metricsMod.default as unknown as Parameters<typeof app.register>[0];
+    await app.register(plugin, { endpoint: '/metrics' });
+  }
+
   // x-request-id propagation
   app.addHook('onRequest', async (req, reply) => {
     const requestId = (req.headers['x-request-id'] as string) || randomUUID();
diff --git a/packages/fastify-core/src/types.ts b/packages/fastify-core/src/types.ts
index fd15bf93..bcef1b9a 100644
--- a/packages/fastify-core/src/types.ts
+++ b/packages/fastify-core/src/types.ts
@@ -1,11 +1,19 @@
 import type { FastifyInstance } from 'fastify';
 
+export interface SwaggerOptions {
+  title: string;
+  description?: string;
+  port?: number;
+}
+
 export interface ServiceAppOptions {
   name: string;
   version: string;
   description?: string;
   corsOrigin?: string;
   logger?: boolean;
+  swagger?: SwaggerOptions;
+  metrics?: boolean;
 }
 
 export interface StartOptions {
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 49307c27..f6440e99 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -105,6 +105,13 @@ importers:
       fastify:
         specifier: '>=5.0.0'
         version: 5.7.4
+    devDependencies:
+      '@fastify/swagger':
+        specifier: ^9.7.0
+        version: 9.7.0
+      fastify-metrics:
+        specifier: ^10.6.0
+        version: 10.6.0(fastify@5.7.4)
 
   packages/logger: {}
 
@@ -131,6 +138,9 @@ importers:
       '@bytelyst/errors':
         specifier: workspace:*
         version: link:../../packages/errors
+      '@bytelyst/fastify-core':
+        specifier: workspace:*
+        version: link:../../packages/fastify-core
       '@fastify/cors':
         specifier: ^10.0.2
         version: 10.1.0
@@ -177,6 +187,9 @@ importers:
       '@bytelyst/errors':
         specifier: workspace:*
         version: link:../../packages/errors
+      '@bytelyst/fastify-core':
+        specifier: workspace:*
+        version: link:../../packages/fastify-core
       '@fastify/cors':
         specifier: ^10.0.2
         version: 10.1.0
@@ -238,6 +251,9 @@ importers:
       '@bytelyst/errors':
         specifier: workspace:*
         version: link:../../packages/errors
+      '@bytelyst/fastify-core':
+        specifier: workspace:*
+        version: link:../../packages/fastify-core
       '@fastify/cors':
         specifier: ^10.0.2
         version: 10.1.0
@@ -290,6 +306,9 @@ importers:
       '@bytelyst/errors':
         specifier: workspace:*
         version: link:../../packages/errors
+      '@bytelyst/fastify-core':
+        specifier: workspace:*
+        version: link:../../packages/fastify-core
       '@fastify/cors':
         specifier: ^10.0.2
         version: 10.1.0
diff --git a/services/billing-service/package.json b/services/billing-service/package.json
index 1bfe9d17..409fb71f 100644
--- a/services/billing-service/package.json
+++ b/services/billing-service/package.json
@@ -16,6 +16,7 @@
     "@bytelyst/config": "workspace:*",
     "@bytelyst/cosmos": "workspace:*",
     "@bytelyst/errors": "workspace:*",
+    "@bytelyst/fastify-core": "workspace:*",
     "@azure/cosmos": "^4.2.0",
     "fastify": "^5.2.1",
     "@fastify/cors": "^10.0.2",
diff --git a/services/billing-service/src/server.ts b/services/billing-service/src/server.ts
index f0a637c5..b94f4c6a 100644
--- a/services/billing-service/src/server.ts
+++ b/services/billing-service/src/server.ts
@@ -5,12 +5,7 @@
  * Port: 4002 (configurable via PORT env var).
  */
 
-import { randomUUID } from 'node:crypto';
-import Fastify from 'fastify';
-import cors from '@fastify/cors';
-import swagger from '@fastify/swagger';
-import metricsPlugin from 'fastify-metrics';
-import { ServiceError } from './lib/errors.js';
+import { createServiceApp, startService } from '@bytelyst/fastify-core';
 import { subscriptionRoutes } from './modules/subscriptions/routes.js';
 import { usageRoutes } from './modules/usage/routes.js';
 import { planRoutes } from './modules/plans/routes.js';
@@ -18,50 +13,20 @@ import { licenseRoutes } from './modules/licenses/routes.js';
 import { stripeRoutes } from './modules/stripe/routes.js';
 import { config } from './lib/config.js';
 
-const PORT = config.PORT;
-const HOST = config.HOST;
-
-const app = Fastify({ logger: true });
-
-// CORS — restrict to specific origins in production via CORS_ORIGIN (comma-separated)
-const corsOrigin = config.CORS_ORIGIN;
-await app.register(cors, {
-  origin: corsOrigin ? corsOrigin.split(',').map(o => o.trim()) : true,
-});
-
-// OpenAPI spec auto-generation (GET /api/docs/json)
-await app.register(swagger, {
-  openapi: {
-    info: {
-      title: 'Billing & Entitlement Service',
-      version: '0.1.0',
-      description: 'Subscriptions, payments, usage, licenses, plans, Stripe',
-    },
-    servers: [{ url: `http://localhost:${PORT}` }],
-  },
-});
-
-// Prometheus metrics
-await app.register(metricsPlugin, { endpoint: '/metrics' });
-
-// x-request-id: propagate incoming header or generate a new one
-app.addHook('onRequest', async (req, reply) => {
-  const requestId = (req.headers['x-request-id'] as string) || randomUUID();
-  req.headers['x-request-id'] = requestId;
-  reply.header('x-request-id', requestId);
-  req.log = req.log.child({ requestId });
-});
-
-// Health check
-app.get('/health', async req => ({
-  status: 'ok',
-  service: 'billing-service',
+const app = await createServiceApp({
+  name: 'billing-service',
   version: '0.1.0',
-  timestamp: new Date().toISOString(),
-  requestId: req.headers['x-request-id'],
-}));
+  description: 'Subscriptions, payments, usage, licenses, plans, Stripe',
+  corsOrigin: config.CORS_ORIGIN,
+  swagger: {
+    title: 'Billing & Entitlement Service',
+    description: 'Subscriptions, payments, usage, licenses, plans, Stripe',
+    port: config.PORT,
+  },
+  metrics: true,
+});
 
-// Internal API key auth (skip health, webhook, and when key not configured)
+// Internal API key auth (service-specific — skip health, webhook, and when key not configured)
 const INTERNAL_KEY = config.BILLING_INTERNAL_KEY;
 if (INTERNAL_KEY) {
   app.addHook('onRequest', async (req, reply) => {
@@ -75,18 +40,6 @@ if (INTERNAL_KEY) {
   });
 }
 
-// Custom error handler
-app.setErrorHandler((error, _req, reply) => {
-  if (error instanceof ServiceError) {
-    const body: Record<string, unknown> = { error: error.message };
-    if ('details' in error && error.details) body.details = error.details;
-    reply.code(error.statusCode).send(body);
-    return;
-  }
-  app.log.error(error);
-  reply.code(500).send({ error: 'Internal server error' });
-});
-
 // Register route modules
 await app.register(subscriptionRoutes, { prefix: '/api' });
 await app.register(usageRoutes, { prefix: '/api' });
@@ -94,11 +47,4 @@ await app.register(planRoutes, { prefix: '/api' });
 await app.register(licenseRoutes, { prefix: '/api' });
 await app.register(stripeRoutes, { prefix: '/api' });
 
-// Start
-try {
-  await app.listen({ port: PORT, host: HOST });
-  app.log.info(`Billing Service listening on ${HOST}:${PORT}`);
-} catch (err) {
-  app.log.error(err);
-  process.exit(1);
-}
+await startService(app, { port: config.PORT, host: config.HOST });
diff --git a/services/growth-service/package.json b/services/growth-service/package.json
index fd71994d..5327e276 100644
--- a/services/growth-service/package.json
+++ b/services/growth-service/package.json
@@ -16,6 +16,7 @@
     "@bytelyst/config": "workspace:*",
     "@bytelyst/cosmos": "workspace:*",
     "@bytelyst/errors": "workspace:*",
+    "@bytelyst/fastify-core": "workspace:*",
     "@azure/cosmos": "^4.2.0",
     "fastify": "^5.2.1",
     "@fastify/cors": "^10.0.2",
diff --git a/services/growth-service/src/server.ts b/services/growth-service/src/server.ts
index 82331c8f..d28bf62e 100644
--- a/services/growth-service/src/server.ts
+++ b/services/growth-service/src/server.ts
@@ -5,66 +5,23 @@
  * Port: 4001 (configurable via PORT env var).
  */
 
-import { randomUUID } from 'node:crypto';
-import Fastify from 'fastify';
-import cors from '@fastify/cors';
-import swagger from '@fastify/swagger';
-import metricsPlugin from 'fastify-metrics';
-import { ServiceError } from './lib/errors.js';
+import { createServiceApp, startService } from '@bytelyst/fastify-core';
 import { invitationRoutes } from './modules/invitations/routes.js';
 import { referralRoutes } from './modules/referrals/routes.js';
 import { promoRoutes } from './modules/promos/routes.js';
 import { config } from './lib/config.js';
 
-const PORT = config.PORT;
-const HOST = config.HOST;
-
-const app = Fastify({ logger: true });
-
-// CORS — restrict to specific origins in production via CORS_ORIGIN (comma-separated)
-const corsOrigin = config.CORS_ORIGIN;
-await app.register(cors, {
-  origin: corsOrigin ? corsOrigin.split(',').map(o => o.trim()) : true,
-});
-
-// OpenAPI spec auto-generation (GET /api/docs/json)
-await app.register(swagger, {
-  openapi: {
-    info: {
-      title: 'Growth Service',
-      version: '0.1.0',
-      description: 'Invitations, referrals, promo codes',
-    },
-    servers: [{ url: `http://localhost:${PORT}` }],
-  },
-});
-// Prometheus metrics
-await app.register(metricsPlugin, { endpoint: '/metrics' });
-// x-request-id: propagate incoming header or generate a new one
-app.addHook('onRequest', async (req, reply) => {
-  const requestId = (req.headers['x-request-id'] as string) || randomUUID();
-  req.headers['x-request-id'] = requestId;
-  reply.header('x-request-id', requestId);
-  req.log = req.log.child({ requestId });
-});
-
-// Health check
-app.get('/health', async req => ({
-  status: 'ok',
-  service: 'growth-service',
+const app = await createServiceApp({
+  name: 'growth-service',
   version: '0.1.0',
-  timestamp: new Date().toISOString(),
-  requestId: req.headers['x-request-id'],
-}));
-
-// Custom error handler for ServiceError
-app.setErrorHandler((error, _req, reply) => {
-  if (error instanceof ServiceError) {
-    reply.code(error.statusCode).send({ error: error.message });
-    return;
-  }
-  app.log.error(error);
-  reply.code(500).send({ error: 'Internal server error' });
+  description: 'Invitations, referrals, promo codes',
+  corsOrigin: config.CORS_ORIGIN,
+  swagger: {
+    title: 'Growth Service',
+    description: 'Invitations, referrals, promo codes',
+    port: config.PORT,
+  },
+  metrics: true,
 });
 
 // Register route modules
@@ -72,11 +29,4 @@ await app.register(invitationRoutes, { prefix: '/api' });
 await app.register(referralRoutes, { prefix: '/api' });
 await app.register(promoRoutes, { prefix: '/api' });
 
-// Start
-try {
-  await app.listen({ port: PORT, host: HOST });
-  app.log.info(`Growth Service listening on ${HOST}:${PORT}`);
-} catch (err) {
-  app.log.error(err);
-  process.exit(1);
-}
+await startService(app, { port: config.PORT, host: config.HOST });
diff --git a/services/platform-service/package.json b/services/platform-service/package.json
index cba4c8bc..4111699f 100644
--- a/services/platform-service/package.json
+++ b/services/platform-service/package.json
@@ -16,6 +16,7 @@
     "@bytelyst/config": "workspace:*",
     "@bytelyst/cosmos": "workspace:*",
     "@bytelyst/errors": "workspace:*",
+    "@bytelyst/fastify-core": "workspace:*",
     "@azure/cosmos": "^4.2.0",
     "@azure/storage-blob": "^12.31.0",
     "@fastify/cors": "^10.0.2",
diff --git a/services/platform-service/src/server.ts b/services/platform-service/src/server.ts
index 50dcdc4c..49a7355f 100644
--- a/services/platform-service/src/server.ts
+++ b/services/platform-service/src/server.ts
@@ -5,12 +5,7 @@
  * Port: 4003 (configurable via PORT env var).
  */
 
-import { randomUUID } from 'node:crypto';
-import Fastify from 'fastify';
-import cors from '@fastify/cors';
-import swagger from '@fastify/swagger';
-import metricsPlugin from 'fastify-metrics';
-import { ServiceError } from './lib/errors.js';
+import { createServiceApp, startService } from '@bytelyst/fastify-core';
 import { authRoutes } from './modules/auth/routes.js';
 import { auditRoutes } from './modules/audit/routes.js';
 import { notificationRoutes } from './modules/notifications/routes.js';
@@ -19,57 +14,17 @@ import { rateLimitRoutes } from './modules/ratelimit/routes.js';
 import { blobRoutes } from './modules/blob/routes.js';
 import { config } from './lib/config.js';
 
-const PORT = config.PORT;
-const HOST = config.HOST;
-
-const app = Fastify({ logger: true });
-
-// CORS — restrict to specific origins in production via CORS_ORIGIN (comma-separated)
-const corsOrigin = config.CORS_ORIGIN;
-await app.register(cors, {
-  origin: corsOrigin ? corsOrigin.split(',').map(o => o.trim()) : true,
-});
-
-// OpenAPI spec auto-generation (GET /api/docs/json)
-await app.register(swagger, {
-  openapi: {
-    info: {
-      title: 'Platform Service',
-      version: '0.1.0',
-      description: 'Auth, audit, notifications, feature flags, rate limiting',
-    },
-    servers: [{ url: `http://localhost:${PORT}` }],
-  },
-});
-
-// Prometheus metrics
-await app.register(metricsPlugin, { endpoint: '/metrics' });
-
-// x-request-id: propagate incoming header or generate a new one
-app.addHook('onRequest', async (req, reply) => {
-  const requestId = (req.headers['x-request-id'] as string) || randomUUID();
-  req.headers['x-request-id'] = requestId;
-  reply.header('x-request-id', requestId);
-  req.log = req.log.child({ requestId });
-});
-
-// Health check
-app.get('/health', async req => ({
-  status: 'ok',
-  service: 'platform-service',
+const app = await createServiceApp({
+  name: 'platform-service',
   version: '0.1.0',
-  timestamp: new Date().toISOString(),
-  requestId: req.headers['x-request-id'],
-}));
-
-// Custom error handler
-app.setErrorHandler((error, _req, reply) => {
-  if (error instanceof ServiceError) {
-    reply.code(error.statusCode).send({ error: error.message });
-    return;
-  }
-  app.log.error(error);
-  reply.code(500).send({ error: 'Internal server error' });
+  description: 'Auth, audit, notifications, feature flags, rate limiting',
+  corsOrigin: config.CORS_ORIGIN,
+  swagger: {
+    title: 'Platform Service',
+    description: 'Auth, audit, notifications, feature flags, rate limiting',
+    port: config.PORT,
+  },
+  metrics: true,
 });
 
 // Register route modules
@@ -80,11 +35,4 @@ await app.register(flagRoutes, { prefix: '/api' });
 await app.register(rateLimitRoutes, { prefix: '/api' });
 await app.register(blobRoutes, { prefix: '/api' });
 
-// Start
-try {
-  await app.listen({ port: PORT, host: HOST });
-  app.log.info(`Platform Service listening on ${HOST}:${PORT}`);
-} catch (err) {
-  app.log.error(err);
-  process.exit(1);
-}
+await startService(app, { port: config.PORT, host: config.HOST });
diff --git a/services/tracker-service/package.json b/services/tracker-service/package.json
index 8aa6da3d..e10e79f2 100644
--- a/services/tracker-service/package.json
+++ b/services/tracker-service/package.json
@@ -16,6 +16,7 @@
     "@bytelyst/config": "workspace:*",
     "@bytelyst/cosmos": "workspace:*",
     "@bytelyst/errors": "workspace:*",
+    "@bytelyst/fastify-core": "workspace:*",
     "@azure/cosmos": "^4.2.0",
     "@fastify/cors": "^10.0.2",
     "@fastify/rate-limit": "^10.3.0",
diff --git a/services/tracker-service/src/server.ts b/services/tracker-service/src/server.ts
index 9ff46c44..c39b2139 100644
--- a/services/tracker-service/src/server.ts
+++ b/services/tracker-service/src/server.ts
@@ -6,69 +6,24 @@
  * Product-agnostic: all data scoped by productId.
  */
 
-import { randomUUID } from 'node:crypto';
-import Fastify from 'fastify';
-import cors from '@fastify/cors';
-import swagger from '@fastify/swagger';
-import metricsPlugin from 'fastify-metrics';
-import { ServiceError } from './lib/errors.js';
+import { createServiceApp, startService } from '@bytelyst/fastify-core';
 import { itemRoutes } from './modules/items/routes.js';
 import { commentRoutes } from './modules/comments/routes.js';
 import { voteRoutes } from './modules/votes/routes.js';
 import { publicRoutes } from './modules/public/routes.js';
 import { config } from './lib/config.js';
 
-const PORT = config.PORT;
-const HOST = config.HOST;
-
-const app = Fastify({ logger: true });
-
-// CORS — restrict to specific origins in production via CORS_ORIGIN (comma-separated)
-const corsOrigin = config.CORS_ORIGIN;
-await app.register(cors, {
-  origin: corsOrigin ? corsOrigin.split(',').map(o => o.trim()) : true,
-});
-
-// OpenAPI spec auto-generation (GET /api/docs/json)
-await app.register(swagger, {
-  openapi: {
-    info: {
-      title: 'Tracker Service',
-      version: '0.1.0',
-      description: 'Feature requests, bugs, tasks — product-agnostic',
-    },
-    servers: [{ url: `http://localhost:${PORT}` }],
-  },
-});
-
-// Prometheus metrics
-await app.register(metricsPlugin, { endpoint: '/metrics' });
-
-// x-request-id: propagate incoming header or generate a new one
-app.addHook('onRequest', async (req, reply) => {
-  const requestId = (req.headers['x-request-id'] as string) || randomUUID();
-  req.headers['x-request-id'] = requestId;
-  reply.header('x-request-id', requestId);
-  req.log = req.log.child({ requestId });
-});
-
-// Health check
-app.get('/health', async req => ({
-  status: 'ok',
-  service: 'tracker-service',
+const app = await createServiceApp({
+  name: 'tracker-service',
   version: '0.1.0',
-  timestamp: new Date().toISOString(),
-  requestId: req.headers['x-request-id'],
-}));
-
-// Custom error handler
-app.setErrorHandler((error, _req, reply) => {
-  if (error instanceof ServiceError) {
-    reply.code(error.statusCode).send({ error: error.message });
-    return;
-  }
-  app.log.error(error);
-  reply.code(500).send({ error: 'Internal server error' });
+  description: 'Feature requests, bugs, tasks — product-agnostic',
+  corsOrigin: config.CORS_ORIGIN,
+  swagger: {
+    title: 'Tracker Service',
+    description: 'Feature requests, bugs, tasks — product-agnostic',
+    port: config.PORT,
+  },
+  metrics: true,
 });
 
 // Register route modules
@@ -77,11 +32,4 @@ await app.register(commentRoutes, { prefix: '/api' });
 await app.register(voteRoutes, { prefix: '/api' });
 await app.register(publicRoutes, { prefix: '/api' });
 
-// Start
-try {
-  await app.listen({ port: PORT, host: HOST });
-  app.log.info(`Tracker Service listening on ${HOST}:${PORT}`);
-} catch (err) {
-  app.log.error(err);
-  process.exit(1);
-}
+await startService(app, { port: config.PORT, host: config.HOST });