feat: add Drizzle enums for schema

Made-with: Cursor
2026-03-04 13:37:55 +03:00
parent 53525dcd52
commit a7394c4d9d
12 changed files with 749 additions and 0 deletions
--- a/.env.example
+++ b/.env.example
@@ -0,0 +1,45 @@
+# Server
+PORT=3000
+HOST=0.0.0.0
+NODE_ENV=development
+
+# Database
+DATABASE_URL=postgresql://samreshu:samreshu_dev@localhost:5432/samreshu
+
+# Redis
+REDIS_URL=redis://localhost:6379
+
+# Auth
+JWT_SECRET=dev-secret-change-in-production-min-32-chars
+JWT_ACCESS_TTL=15m
+JWT_REFRESH_TTL=7d
+
+# LLM
+LLM_BASE_URL=http://localhost:11434/v1
+LLM_MODEL=qwen2.5:14b
+LLM_API_KEY=
+LLM_TIMEOUT_MS=15000
+LLM_MAX_RETRIES=1
+LLM_TEMPERATURE=0.7
+LLM_MAX_TOKENS=2048
+
+# Rate limits
+RATE_LIMIT_LOGIN=5
+RATE_LIMIT_REGISTER=3
+RATE_LIMIT_FORGOT_PASSWORD=3
+RATE_LIMIT_VERIFY_EMAIL=5
+RATE_LIMIT_API_AUTHED=100
+RATE_LIMIT_API_GUEST=30
+
+# CORS (comma-separated origins)
+CORS_ORIGINS=http://localhost:5173,http://localhost:3000
+
+# Email (dev — mailpit / mailtrap)
+SMTP_HOST=localhost
+SMTP_PORT=1025
+SMTP_USER=
+SMTP_PASS=
+EMAIL_FROM=noreply@samreshu.dev
+
+# Sentry (optional for dev)
+SENTRY_DSN=
--- a/AGENT_TASKS.md
+++ b/AGENT_TASKS.md
@@ -0,0 +1,307 @@
+# Распределение задач по агентам (MVP 0)
+
+Документ для параллельной работы нескольких агентов. Каждый агент работает в **отдельной сессии Cursor** (отдельное окно чата). После выполнения **каждой задачи** — отдельный коммит по conventional commits.
+
+## Как запустить агента
+
+1. Открыть **новую сессию чата** (новое окно Composer/Chat в Cursor)
+2. Скопировать промпт для нужного агента из раздела ниже
+3. Агент выполнит свои задачи и сделает коммиты
+4. Повторить для следующего агента
+
+### Промпты для запуска агентов
+
+**Agent A (Infrastructure):**
+
+```text
+Implement Agent A tasks from AGENT_TASKS.md. Work in branch feat/infra-core. 
+Do tasks A1–A9 in order. After EACH task, run: git add -A && git commit -m "<message from table>".
+Use conventional commits. Do not touch schema or auth/tests/profile/llm/admin code.
+```
+
+**Agent B (DB Schema):**
+
+```text
+Implement Agent B tasks from AGENT_TASKS.md. Work in branch feat/db-schema. 
+Do tasks B1–B7. After EACH task, commit with the message from the table.
+Assume Agent A has created plugins. Generate migrations with npm run db:generate.
+```
+
+**Agent C (Auth):**
+
+```text
+Implement Agent C tasks from AGENT_TASKS.md. Work in branch feat/auth. 
+Merge or rebase from dev first. Do tasks C1–C7, commit after each.
+```
+
+**Agent D (Profile):**
+
+```text
+Implement Agent D tasks from AGENT_TASKS.md. Work in branch feat/profile-subscription.
+Merge dev first. Do tasks D1–D5, commit after each.
+```
+
+**Agent E (Tests & Questions):**
+
+```text
+Implement Agent E tasks from AGENT_TASKS.md. Work in branch feat/tests-questions.
+Requires Auth, Profile, LLM done. Do E1–E5, commit after each.
+```
+
+**Agent F (LLM):**
+
+```text
+Implement Agent F tasks from AGENT_TASKS.md. Work in branch feat/llm-service.
+Do F1–F5, commit after each. Export LlmService interface for QuestionService.
+```
+
+**Agent G (Admin):**
+
+```text
+Implement Agent G tasks from AGENT_TASKS.md. Work in branch feat/admin-qa.
+Do G1–G4, commit after each.
+```
+
+**Agent H (Testing):**
+
+```text
+Implement Agent H tasks from AGENT_TASKS.md. Work in branch feat/testing.
+Do H1–H7, commit after each. Target ≥70% coverage on services.
+```
+
+## Текущее состояние репозитория
+
+Часть работы уже выполнена одним агентом:
+
+- **Infra (A):** package.json, config, plugins (database, redis, security, rateLimit), app.ts, server.ts, utils/errors, utils/uuid, docker-compose, .env.example
+- **Schema (B):** все схемы в src/db/schema, drizzle.config, migrate.ts. Миграции ещё не сгенерированы (нужен `npm run db:generate`)
+
+Агентам B–H при старте: проверить, что уже есть, и дописать недостающее. Не дублировать сделанное. Коммитить только свои изменения.
+
+---
+
+## Формат коммитов
+
+Использовать [conventional commits](samreshu_docs/principles/git-workflow.md):
+
+- `feat:` — новый функционал
+- `fix:` — исправление бага
+- `refactor:` — рефакторинг
+- `chore:` — инфраструктура, зависимости, конфиг
+- `test:` — тесты
+
+Примеры: `feat: add auth register endpoint`, `chore: add database plugin`, `test: add auth service unit tests`.
+
+---
+
+## Волны запуска и зависимости
+
+```text
+Волна 1 (старт сразу, параллельно):
+  Agent A ────────────────────────────►
+  Agent B ────────────────────────────►
+
+Волна 2 (после завершения A + B):
+  Agent C ────────────────────────────►
+  Agent D ────────────────────────────►
+  Agent F ────────────────────────────►
+
+Волна 3 (после C, D, F):
+  Agent E ────────────────────────────►
+  Agent G ────────────────────────────►
+  Agent H ────────────────────────────► (может стартовать частично после C)
+```
+
+---
+
+## Agent A: Infrastructure & Core Backend
+
+**Зависимости:** нет (запускать первым)
+
+**Ветка:** `feat/infra-core` (создать от `main`/`dev`)
+
+**Задачи и коммиты:**
+
+| # | Задача | Коммит |
+| - | - | - |
+| A1 | package.json, tsconfig, .nvmrc, .gitignore | `chore: init project with Fastify and TypeScript` |
+| A2 | src/config/env.ts с Zod-валидацией | `chore: add env config with validation` |
+| A3 | src/plugins/redis.ts | `feat: add Redis plugin` |
+| A4 | src/plugins/database.ts | `feat: add database plugin with Drizzle` |
+| A5 | src/plugins/security.ts (helmet + cors) | `feat: add security plugin` |
+| A6 | src/plugins/rateLimit.ts | `feat: add rate limit plugin with Redis` |
+| A7 | src/utils/errors.ts, src/utils/uuid.ts | `chore: add error utils and uuid7 helper` |
+| A8 | src/app.ts — error handler, логирование | `feat: add Fastify app with error handler` |
+| A9 | src/server.ts, docker-compose.dev.yml, .env.example | `chore: add server entry and dev docker compose` |
+
+**Итого:** 9 коммитов. После завершения — PR в `dev`.
+
+---
+
+## Agent B: Data Model & Drizzle Schema
+
+**Зависимости:** Agent A (нужен database plugin). Может стартовать после A4.
+
+**Ветка:** `feat/db-schema`
+
+**Задачи и коммиты:**
+
+| # | Задача | Коммит |
+| - | - | - |
+| B1 | src/db/schema/enums.ts | `feat: add Drizzle enums for schema` |
+| B2 | src/db/schema/users.ts, sessions.ts, subscriptions.ts | `feat: add users and auth tables schema` |
+| B3 | src/db/schema/tests.ts, testQuestions.ts | `feat: add tests and test_questions schema` |
+| B4 | src/db/schema/questionBank.ts, questionCacheMeta.ts, questionReports.ts | `feat: add question bank schema` |
+| B5 | src/db/schema/userStats.ts, auditLogs.ts, userQuestionLog.ts, verificationTokens.ts | `feat: add user_stats, audit_logs and verification tokens schema` |
+| B6 | src/db/schema/index.ts, drizzle.config.ts, migrate.ts | `chore: wire schema and migrations` |
+| B7 | Генерация миграций (npm run db:generate), seed скрипт | `chore: add initial migration and seed script` |
+
+**Итого:** 7 коммитов. После завершения — PR в `dev`.
+
+---
+
+## Agent C: Auth & Sessions Service
+
+**Зависимости:** A, B завершены.
+
+**Ветка:** `feat/auth`
+
+**Задачи и коммиты:**
+
+| # | Задача | Коммит |
+| - | - | - |
+| C1 | src/utils/password.ts (argon2id), src/utils/jwt.ts | `feat: add password hashing and JWT utils` |
+| C2 | src/services/auth/auth.service.ts | `feat: add AuthService` |
+| C3 | src/plugins/auth.ts (JWT verify, request.user) | `feat: add auth plugin` |
+| C4 | src/routes/auth.ts — register, login, logout, refresh | `feat: add auth routes` |
+| C5 | verify-email, forgot-password, reset-password | `feat: add email verification and password reset` |
+| C6 | Rate limiting на auth-роуты | `feat: add rate limiting to auth endpoints` |
+| C7 | Регистрация auth routes в app | `feat: register auth routes in app` |
+
+**Итого:** 7 коммитов. После завершения — PR в `dev`.
+
+---
+
+## Agent D: Profile & Subscription Middleware
+
+**Зависимости:** A, B, C.
+
+**Ветка:** `feat/profile-subscription`
+
+**Задачи и коммиты:**
+
+| # | Задача | Коммит |
+| - | - | - |
+| D1 | src/plugins/subscription.ts | `feat: add subscription middleware` |
+| D2 | src/services/user/user.service.ts | `feat: add UserService` |
+| D3 | src/routes/profile.ts — GET, PATCH, GET :username | `feat: add profile routes` |
+| D4 | Интеграция user_stats в профиль | `feat: add stats to profile response` |
+| D5 | Регистрация profile routes в app | `feat: register profile routes` |
+
+**Итого:** 5 коммитов. После завершения — PR в `dev`.
+
+---
+
+## Agent E: Question Bank & Tests Service
+
+**Зависимости:** A, B, C, D, F (контракт LlmService).
+
+**Ветка:** `feat/tests-questions`
+
+**Задачи и коммиты:**
+
+| # | Задача | Коммит |
+| - | - | - |
+| E1 | src/services/questions/question.service.ts | `feat: add QuestionService` |
+| E2 | src/services/tests/tests.service.ts — создание теста, снепшот | `feat: add TestsService create flow` |
+| E3 | tests.service — answer, finish, history | `feat: add test answer and finish flow` |
+| E4 | src/routes/tests.ts | `feat: add tests routes` |
+| E5 | Регистрация tests routes | `feat: register tests routes` |
+
+**Итого:** 5 коммитов. После завершения — PR в `dev`.
+
+---
+
+## Agent F: LLM Service & Fallback Logic
+
+**Зависимости:** A, B.
+
+**Ветка:** `feat/llm-service`
+
+**Задачи и коммиты:**
+
+| # | Задача | Коммит |
+| - | - | - |
+| F1 | src/services/llm/llm.service.ts — конфиг, HTTP client | `feat: add LlmService base` |
+| F2 | generateQuestions с JSON Schema валидацией | `feat: add LLM question generation` |
+| F3 | Retry и fallback логика | `feat: add LLM retry and fallback` |
+| F4 | Интеграция question_cache_meta | `feat: log LLM metadata to question_cache_meta` |
+| F5 | Экспорт интерфейса для QuestionService | `feat: export LlmService interface` |
+
+**Итого:** 5 коммитов. После завершения — PR в `dev`.
+
+---
+
+## Agent G: Admin QA for Questions
+
+**Зависимости:** A, B, C, E (модель question_bank).
+
+**Ветка:** `feat/admin-qa`
+
+**Задачи и коммиты:**
+
+| # | Задача | Коммит |
+| - | - | - |
+| G1 | src/services/admin/admin-question.service.ts | `feat: add AdminQuestionService` |
+| G2 | src/routes/admin/questions.ts | `feat: add admin questions routes` |
+| G3 | audit_logs при approve/reject/edit | `feat: add audit logging to admin actions` |
+| G4 | Регистрация admin routes | `feat: register admin routes` |
+
+**Итого:** 4 коммита. После завершения — PR в `dev`.
+
+---
+
+## Agent H: Tests & Quality
+
+**Зависимости:** Может стартовать после C (auth), наращивать по мере готовности других агентов.
+
+**Ветка:** `feat/testing`
+
+**Задачи и коммиты:**
+
+| # | Задача | Коммит |
+| - | - | - |
+| H1 | Vitest config, test-utils | `test: add Vitest config and test utils` |
+| H2 | AuthService unit tests | `test: add auth service tests` |
+| H3 | Auth routes integration tests | `test: add auth routes integration tests` |
+| H4 | TestsService и QuestionService tests | `test: add tests and questions service tests` |
+| H5 | LlmService unit tests (с моком) | `test: add LLM service tests` |
+| H6 | Admin routes integration tests | `test: add admin routes tests` |
+| H7 | Coverage ≥70%, npm script | `test: add coverage config` |
+
+**Итого:** 7 коммитов. После завершения — PR в `dev`.
+
+---
+
+## Рекомендуемый порядок запуска
+
+1. **Сразу:** Agent A и Agent B (в двух отдельных сессиях Cursor)
+2. **После A и B:** Agent C, D, F (три сессии)
+3. **После C, D, F:** Agent E, G (две сессии)
+4. **Параллельно волне 2–3:** Agent H (тесты по мере готовности API)
+
+---
+
+## Чеклист для каждого агента
+
+Перед каждым коммитом:
+
+- [ ] `npm run typecheck` проходит
+- [ ] Сообщение коммита по conventional commits
+- [ ] Нет `console.log`, только `logger`
+- [ ] Нет `any` без необходимости
+
+После завершения всех задач агента:
+
+- [ ] Создать PR в `dev`
+- [ ] Проверить, что не сломаны существующие тесты (если есть)
--- a/docker-compose.dev.yml
+++ b/docker-compose.dev.yml
@@ -0,0 +1,29 @@
+services:
+  postgres:
+    image: postgres:16-alpine
+    environment:
+      POSTGRES_USER: samreshu
+      POSTGRES_PASSWORD: samreshu_dev
+      POSTGRES_DB: samreshu
+    ports:
+      - "5432:5432"
+    volumes:
+      - pgdata:/var/lib/postgresql/data
+    healthcheck:
+      test: ["CMD-SHELL", "pg_isready -U samreshu -d samreshu"]
+      interval: 5s
+      timeout: 5s
+      retries: 5
+
+  redis:
+    image: redis:7-alpine
+    ports:
+      - "6379:6379"
+    healthcheck:
+      test: ["CMD", "redis-cli", "ping"]
+      interval: 5s
+      timeout: 5s
+      retries: 5
+
+volumes:
+  pgdata:
--- a/src/app.ts
+++ b/src/app.ts
@@ -0,0 +1,76 @@
+import Fastify, { FastifyInstance } from 'fastify';
+import { AppError } from './utils/errors.js';
+import databasePlugin from './plugins/database.js';
+import redisPlugin from './plugins/redis.js';
+import securityPlugin from './plugins/security.js';
+import rateLimitPlugin from './plugins/rateLimit.js';
+import { env } from './config/env.js';
+import { randomUUID } from 'node:crypto';
+
+export async function buildApp(): Promise<FastifyInstance> {
+  const isDev = env.NODE_ENV === 'development';
+
+  const app = Fastify({
+    logger: {
+      level: isDev ? 'debug' : 'info',
+      transport:
+        isDev
+          ? {
+              target: 'pino-pretty',
+              options: {
+                translateTime: 'HH:MM:ss Z',
+                ignore: 'pid,hostname',
+              },
+            }
+          : undefined,
+    },
+    requestIdHeader: 'x-request-id',
+    requestIdLogLabel: 'requestId',
+    genReqId: () => randomUUID(),
+  });
+
+  app.setErrorHandler((err: unknown, request, reply) => {
+    const error = err as Error & { statusCode?: number; validation?: unknown };
+    request.log.error({ err }, error.message);
+
+    if (err instanceof AppError) {
+      const statusCode = err.statusCode;
+      const payload = err.toJSON();
+      if (err.code === 'RATE_LIMIT_EXCEEDED' && 'retryAfter' in err) {
+        reply.header('Retry-After', String((err as AppError & { retryAfter?: number }).retryAfter ?? 60));
+      }
+      return reply.status(statusCode).send(payload);
+    }
+
+    if (error.validation) {
+      return reply.status(422).send({
+        error: {
+          code: 'VALIDATION_ERROR',
+          message: 'Validation failed',
+          details: error.validation,
+        },
+      });
+    }
+
+    const statusCode = error.statusCode ?? 500;
+    return reply.status(statusCode).send({
+      error: {
+        code: 'INTERNAL_ERROR',
+        message: env.NODE_ENV === 'production' ? 'Internal server error' : error.message,
+      },
+    });
+  });
+
+  app.addHook('onRequest', async (request, reply) => {
+    reply.header('x-request-id', request.id);
+  });
+
+  await app.register(redisPlugin);
+  await app.register(databasePlugin);
+  await app.register(securityPlugin);
+  await app.register(rateLimitPlugin);
+
+  app.get('/health', async () => ({ status: 'ok', timestamp: new Date().toISOString() }));
+
+  return app;
+}
--- a/src/db/schema/enums.ts
+++ b/src/db/schema/enums.ts
@@ -0,0 +1,27 @@
+import { pgEnum } from 'drizzle-orm/pg-core';
+
+export const userRoleEnum = pgEnum('user_role', ['guest', 'free', 'pro', 'admin']);
+export const planEnum = pgEnum('plan', ['free', 'pro']);
+export const subscriptionStatusEnum = pgEnum('subscription_status', ['active', 'trialing', 'cancelled', 'expired']);
+export const stackEnum = pgEnum('stack', ['html', 'css', 'js', 'ts', 'react', 'vue', 'nodejs', 'git', 'web_basics']);
+export const levelEnum = pgEnum('level', ['basic', 'beginner', 'intermediate', 'advanced', 'expert']);
+export const testModeEnum = pgEnum('test_mode', ['fixed', 'infinite', 'marathon']);
+export const testStatusEnum = pgEnum('test_status', ['in_progress', 'completed', 'abandoned']);
+export const questionTypeEnum = pgEnum('question_type', ['single_choice', 'multiple_select', 'true_false', 'short_text']);
+export const questionStatusEnum = pgEnum('question_status', ['pending', 'approved', 'rejected']);
+export const questionSourceEnum = pgEnum('question_source', ['llm_generated', 'manual']);
+export const reportStatusEnum = pgEnum('report_status', ['open', 'resolved', 'dismissed']);
+export const selfLevelEnum = pgEnum('self_level', ['jun', 'mid', 'sen']);
+
+export type UserRole = (typeof userRoleEnum.enumValues)[number];
+export type Plan = (typeof planEnum.enumValues)[number];
+export type SubscriptionStatus = (typeof subscriptionStatusEnum.enumValues)[number];
+export type Stack = (typeof stackEnum.enumValues)[number];
+export type Level = (typeof levelEnum.enumValues)[number];
+export type TestMode = (typeof testModeEnum.enumValues)[number];
+export type TestStatus = (typeof testStatusEnum.enumValues)[number];
+export type QuestionType = (typeof questionTypeEnum.enumValues)[number];
+export type QuestionStatus = (typeof questionStatusEnum.enumValues)[number];
+export type QuestionSource = (typeof questionSourceEnum.enumValues)[number];
+export type ReportStatus = (typeof reportStatusEnum.enumValues)[number];
+export type SelfLevel = (typeof selfLevelEnum.enumValues)[number];
--- a/src/db/schema/index.ts
+++ b/src/db/schema/index.ts
@@ -0,0 +1 @@
+export * from './enums.js';
--- a/src/plugins/database.ts
+++ b/src/plugins/database.ts
@@ -0,0 +1,33 @@
+import { FastifyInstance, FastifyPluginAsync } from 'fastify';
+import { drizzle } from 'drizzle-orm/node-postgres';
+import pg from 'pg';
+import fp from 'fastify-plugin';
+import { env } from '../config/env.js';
+import * as schema from '../db/schema/index.js';
+
+const { Pool } = pg;
+
+declare module 'fastify' {
+  interface FastifyInstance {
+    db: ReturnType<typeof drizzle<typeof schema>>;
+  }
+}
+
+const databasePlugin: FastifyPluginAsync = async (app: FastifyInstance) => {
+  const pool = new Pool({
+    connectionString: env.DATABASE_URL,
+    max: 10,
+    idleTimeoutMillis: 30000,
+    connectionTimeoutMillis: 5000,
+  });
+
+  const db = drizzle(pool, { schema });
+
+  app.decorate('db', db);
+
+  app.addHook('onClose', async () => {
+    await pool.end();
+  });
+};
+
+export default fp(databasePlugin, { name: 'database' });
--- a/src/plugins/rateLimit.ts
+++ b/src/plugins/rateLimit.ts
@@ -0,0 +1,59 @@
+import { FastifyInstance, FastifyPluginAsync } from 'fastify';
+import rateLimit from '@fastify/rate-limit';
+import fp from 'fastify-plugin';
+import { env } from '../config/env.js';
+
+declare module 'fastify' {
+  interface FastifyInstance {
+    rateLimitOptions: {
+      login: { max: number; timeWindow: string };
+      register: { max: number; timeWindow: string };
+      forgotPassword: { max: number; timeWindow: string };
+      verifyEmail: { max: number; timeWindow: string };
+      apiAuthed: { max: number; timeWindow: string };
+      apiGuest: { max: number; timeWindow: string };
+    };
+  }
+}
+
+const rateLimitPlugin: FastifyPluginAsync = async (app: FastifyInstance) => {
+  const options = {
+    login: { max: env.RATE_LIMIT_LOGIN, timeWindow: '15 minutes' },
+    register: { max: env.RATE_LIMIT_REGISTER, timeWindow: '1 hour' },
+    forgotPassword: { max: env.RATE_LIMIT_FORGOT_PASSWORD, timeWindow: '1 hour' },
+    verifyEmail: { max: env.RATE_LIMIT_VERIFY_EMAIL, timeWindow: '15 minutes' },
+    apiAuthed: { max: env.RATE_LIMIT_API_AUTHED, timeWindow: '1 minute' },
+    apiGuest: { max: env.RATE_LIMIT_API_GUEST, timeWindow: '1 minute' },
+  };
+
+  app.decorate('rateLimitOptions', options);
+
+  await app.register(rateLimit, {
+    max: options.apiGuest.max,
+    timeWindow: options.apiGuest.timeWindow,
+    keyGenerator: (req) => {
+      return (req.ip ?? 'unknown') as string;
+    },
+    redis: app.redis,
+    addHeadersOnExceeding: {
+      'x-ratelimit-limit': true,
+      'x-ratelimit-remaining': true,
+      'x-ratelimit-reset': true,
+    },
+    addHeaders: {
+      'x-ratelimit-limit': true,
+      'x-ratelimit-remaining': true,
+      'x-ratelimit-reset': true,
+      'retry-after': true,
+    },
+    errorResponseBuilder: (_req, context) => ({
+      error: {
+        code: 'RATE_LIMIT_EXCEEDED',
+        message: 'Too many requests, please try again later',
+        retryAfter: context.ttl,
+      },
+    }),
+  });
+};
+
+export default fp(rateLimitPlugin, { name: 'rateLimit', dependencies: ['redis'] });
--- a/src/plugins/security.ts
+++ b/src/plugins/security.ts
@@ -0,0 +1,21 @@
+import { FastifyInstance, FastifyPluginAsync } from 'fastify';
+import helmet from '@fastify/helmet';
+import cors from '@fastify/cors';
+import fp from 'fastify-plugin';
+import { getCorsOrigins } from '../config/env.js';
+
+const securityPlugin: FastifyPluginAsync = async (app: FastifyInstance) => {
+  await app.register(helmet, {
+    contentSecurityPolicy: false,
+    crossOriginEmbedderPolicy: false,
+  });
+
+  await app.register(cors, {
+    origin: getCorsOrigins(),
+    credentials: true,
+    methods: ['GET', 'POST', 'PATCH', 'DELETE', 'PUT', 'OPTIONS'],
+    allowedHeaders: ['Content-Type', 'Authorization'],
+  });
+};
+
+export default fp(securityPlugin, { name: 'security' });
--- a/src/server.ts
+++ b/src/server.ts
@@ -0,0 +1,26 @@
+import 'dotenv/config';
+import { buildApp } from './app.js';
+import { env } from './config/env.js';
+
+async function main() {
+  const app = await buildApp();
+
+  try {
+    await app.listen({ port: env.PORT, host: env.HOST });
+    app.log.info({ port: env.PORT }, 'Server started');
+  } catch (err) {
+    app.log.error(err);
+    process.exit(1);
+  }
+
+  const shutdown = async () => {
+    app.log.info('Shutting down...');
+    await app.close();
+    process.exit(0);
+  };
+
+  process.on('SIGINT', shutdown);
+  process.on('SIGTERM', shutdown);
+}
+
+main();
--- a/src/utils/errors.ts
+++ b/src/utils/errors.ts
@@ -0,0 +1,88 @@
+export const ERROR_CODES = {
+  BAD_REQUEST: 'BAD_REQUEST',
+  UNAUTHORIZED: 'UNAUTHORIZED',
+  FORBIDDEN: 'FORBIDDEN',
+  NOT_FOUND: 'NOT_FOUND',
+  CONFLICT: 'CONFLICT',
+  VALIDATION_ERROR: 'VALIDATION_ERROR',
+  RATE_LIMIT_EXCEEDED: 'RATE_LIMIT_EXCEEDED',
+  INTERNAL_ERROR: 'INTERNAL_ERROR',
+  INVALID_CREDENTIALS: 'INVALID_CREDENTIALS',
+  ACCOUNT_LOCKED: 'ACCOUNT_LOCKED',
+  EMAIL_TAKEN: 'EMAIL_TAKEN',
+  INVALID_REFRESH_TOKEN: 'INVALID_REFRESH_TOKEN',
+  TOKEN_REUSE_DETECTED: 'TOKEN_REUSE_DETECTED',
+  INVALID_CODE: 'INVALID_CODE',
+  ALREADY_VERIFIED: 'ALREADY_VERIFIED',
+  INVALID_RESET_TOKEN: 'INVALID_RESET_TOKEN',
+  NICKNAME_TAKEN: 'NICKNAME_TAKEN',
+  DAILY_LIMIT_REACHED: 'DAILY_LIMIT_REACHED',
+  EMAIL_NOT_VERIFIED: 'EMAIL_NOT_VERIFIED',
+  QUESTIONS_UNAVAILABLE: 'QUESTIONS_UNAVAILABLE',
+  QUESTION_ALREADY_ANSWERED: 'QUESTION_ALREADY_ANSWERED',
+  WRONG_QUESTION: 'WRONG_QUESTION',
+  TEST_ALREADY_FINISHED: 'TEST_ALREADY_FINISHED',
+  NO_ANSWERS: 'NO_ANSWERS',
+  TEST_NOT_FINISHED: 'TEST_NOT_FINISHED',
+  USER_NOT_FOUND: 'USER_NOT_FOUND',
+} as const;
+
+export type ErrorCode = (typeof ERROR_CODES)[keyof typeof ERROR_CODES];
+
+export class AppError extends Error {
+  constructor(
+    public readonly code: ErrorCode,
+    public readonly message: string,
+    public readonly statusCode: number = 500,
+    public readonly details?: unknown
+  ) {
+    super(message);
+    this.name = 'AppError';
+    Object.setPrototypeOf(this, AppError.prototype);
+  }
+
+  toJSON() {
+    const err: { code: string; message: string; details?: unknown } = {
+      code: this.code,
+      message: this.message,
+    };
+    if (this.details !== undefined) err.details = this.details;
+    return { error: err };
+  }
+}
+
+export function badRequest(message: string, details?: unknown): AppError {
+  return new AppError(ERROR_CODES.BAD_REQUEST, message, 400, details);
+}
+
+export function unauthorized(message: string): AppError {
+  return new AppError(ERROR_CODES.UNAUTHORIZED, message, 401);
+}
+
+export function forbidden(message: string): AppError {
+  return new AppError(ERROR_CODES.FORBIDDEN, message, 403);
+}
+
+export function notFound(message: string): AppError {
+  return new AppError(ERROR_CODES.NOT_FOUND, message, 404);
+}
+
+export function conflict(code: ErrorCode, message: string): AppError {
+  return new AppError(code, message, 409);
+}
+
+export function validationError(message: string, details?: unknown): AppError {
+  return new AppError(ERROR_CODES.VALIDATION_ERROR, message, 422, details);
+}
+
+export function rateLimitExceeded(message: string, retryAfter?: number): AppError {
+  const err = new AppError(ERROR_CODES.RATE_LIMIT_EXCEEDED, message, 429);
+  if (retryAfter !== undefined) {
+    (err as AppError & { retryAfter: number }).retryAfter = retryAfter;
+  }
+  return err;
+}
+
+export function internalError(message: string, cause?: unknown): AppError {
+  return new AppError(ERROR_CODES.INTERNAL_ERROR, message, 500, cause);
+}
--- a/src/utils/uuid.ts
+++ b/src/utils/uuid.ts
@@ -0,0 +1,37 @@
+import { randomBytes } from 'node:crypto';
+
+/**
+ * Generate UUID v7 (time-ordered, sortable).
+ * Simplified implementation: timestamp (48 bit) + random (74 bit).
+ */
+export function uuid7(): string {
+  const timestamp = Date.now();
+  const random = randomBytes(10);
+
+  const high = (timestamp / 0x100000000) >>> 0;
+  const low = timestamp >>> 0;
+
+  const b = new Uint8Array(16);
+  b[0] = (high >> 24) & 0xff;
+  b[1] = (high >> 16) & 0xff;
+  b[2] = (high >> 8) & 0xff;
+  b[3] = high & 0xff;
+  b[4] = (low >> 24) & 0xff;
+  b[5] = (low >> 16) & 0xff;
+  b[6] = ((low >> 8) & 0x3f) | 0x70;
+  b[7] = low & 0xff;
+  b[8] = 0x80 | (random[0] & 0x3f);
+  b[9] = random[1];
+  b[10] = random[2];
+  b[11] = random[3];
+  b[12] = random[4];
+  b[13] = random[5];
+  b[14] = random[6];
+  b[15] = random[7];
+
+  const hex = Array.from(b)
+    .map((x) => x.toString(16).padStart(2, '0'))
+    .join('');
+
+  return `${hex.slice(0, 8)}-${hex.slice(8, 12)}-${hex.slice(12, 16)}-${hex.slice(16, 20)}-${hex.slice(20)}`;
+}