diff --git a/docs/TELEGRAM_BOTS.md b/docs/TELEGRAM_BOTS.md
index 7bb3c3145..6e8fb7e8b 100644
--- a/docs/TELEGRAM_BOTS.md
+++ b/docs/TELEGRAM_BOTS.md
@@ -9,7 +9,7 @@ Dokumentation aller Telegram-Bots im ManaCore Monorepo.
 | [telegram-stats-bot](#telegram-stats-bot) | 3300 | Analytics & Statistiken von Umami | ✅ Aktiv |
 | [telegram-ollama-bot](#telegram-ollama-bot) | 3301 | Lokale LLM-Inferenz via Ollama | ✅ Aktiv |
 | [telegram-project-doc-bot](#telegram-project-doc-bot) | 3302 | Projektdokumentation & Blogpost-Generierung | ✅ Aktiv |
-| [telegram-calendar-bot](#telegram-calendar-bot) | 3303 | Kalender-Termine & Erinnerungen | 📋 Geplant |
+| [telegram-calendar-bot](#telegram-calendar-bot) | 3303 | Kalender-Termine & Erinnerungen | 🚧 In Entwicklung |
 
 ## Gemeinsame Architektur
 
diff --git a/services/telegram-calendar-bot/.env.example b/services/telegram-calendar-bot/.env.example
new file mode 100644
index 000000000..e56a68dcd
--- /dev/null
+++ b/services/telegram-calendar-bot/.env.example
@@ -0,0 +1,21 @@
+# Server
+PORT=3303
+NODE_ENV=development
+TZ=Europe/Berlin
+
+# Telegram
+TELEGRAM_BOT_TOKEN=xxx                      # Bot Token from @BotFather
+TELEGRAM_ALLOWED_USERS=                     # Optional: Comma-separated user IDs
+
+# Calendar Backend API
+CALENDAR_API_URL=http://localhost:3016
+MANA_CORE_AUTH_URL=http://localhost:3001
+
+# Database (for telegram user links and reminder settings)
+DATABASE_URL=postgresql://manacore:devpassword@localhost:5432/calendar_bot
+
+# Reminder Settings
+REMINDER_CHECK_INTERVAL=60000               # Check every minute (ms)
+MORNING_BRIEFING_ENABLED=true
+MORNING_BRIEFING_TIME=07:00
+MORNING_BRIEFING_TIMEZONE=Europe/Berlin
diff --git a/services/telegram-calendar-bot/CLAUDE.md b/services/telegram-calendar-bot/CLAUDE.md
new file mode 100644
index 000000000..79c46706b
--- /dev/null
+++ b/services/telegram-calendar-bot/CLAUDE.md
@@ -0,0 +1,290 @@
+# Telegram Calendar Bot
+
+Telegram Bot für die Calendar-App mit Termin-Abfragen, Quick-Add und Erinnerungen.
+
+## Tech Stack
+
+- **Framework**: NestJS 10
+- **Telegram**: nestjs-telegraf + Telegraf
+- **Database**: PostgreSQL + Drizzle ORM
+- **Scheduling**: @nestjs/schedule
+- **Date Handling**: date-fns, date-fns-tz
+
+## Commands
+
+```bash
+# Development
+pnpm start:dev        # Start with hot reload
+
+# Build
+pnpm build            # Production build
+
+# Type check
+pnpm type-check       # Check TypeScript types
+
+# Database
+pnpm db:generate      # Generate migrations
+pnpm db:push          # Push schema to database
+pnpm db:studio        # Open Drizzle Studio
+```
+
+## Telegram Commands
+
+| Command | Beschreibung |
+|---------|--------------|
+| `/start` | Hilfe & Account verknüpfen |
+| `/help` | Verfügbare Befehle anzeigen |
+| `/today` | Heutige Termine |
+| `/tomorrow` | Morgige Termine |
+| `/week` | Wochenübersicht |
+| `/next [n]` | Nächste n Termine (default: 5) |
+| `/add [text]` | Termin hinzufügen |
+| `/calendars` | Kalender-Übersicht |
+| `/remind` | Erinnerungseinstellungen |
+| `/status` | Verbindungsstatus prüfen |
+| `/link` | ManaCore Account verknüpfen |
+| `/unlink` | Account-Verknüpfung trennen |
+
+## Environment Variables
+
+```env
+# Server
+PORT=3303
+NODE_ENV=development
+TZ=Europe/Berlin
+
+# Telegram
+TELEGRAM_BOT_TOKEN=xxx              # Bot Token from @BotFather
+TELEGRAM_ALLOWED_USERS=123,456      # Optional: Comma-separated user IDs
+
+# Calendar Backend API
+CALENDAR_API_URL=http://localhost:3016
+MANA_CORE_AUTH_URL=http://localhost:3001
+
+# Database
+DATABASE_URL=postgresql://manacore:devpassword@localhost:5432/calendar_bot
+
+# Reminder Settings
+REMINDER_CHECK_INTERVAL=60000       # Check every minute (ms)
+MORNING_BRIEFING_ENABLED=true
+MORNING_BRIEFING_TIME=07:00
+MORNING_BRIEFING_TIMEZONE=Europe/Berlin
+```
+
+## Projekt-Struktur
+
+```
+services/telegram-calendar-bot/
+├── src/
+│   ├── main.ts                     # Entry point
+│   ├── app.module.ts               # Root module
+│   ├── health.controller.ts        # Health endpoint
+│   ├── config/
+│   │   └── configuration.ts        # Config & commands
+│   ├── database/
+│   │   ├── database.module.ts      # Drizzle connection
+│   │   └── schema.ts               # DB schema
+│   ├── bot/
+│   │   ├── bot.module.ts
+│   │   ├── bot.update.ts           # Command handlers
+│   │   └── formatters.ts           # Message formatters
+│   ├── calendar/
+│   │   ├── calendar.module.ts
+│   │   └── calendar.client.ts      # Calendar API client
+│   ├── user/
+│   │   ├── user.module.ts
+│   │   └── user.service.ts         # User management
+│   └── reminder/
+│       ├── reminder.module.ts
+│       ├── reminder.service.ts     # Sent reminders tracking
+│       └── reminder.scheduler.ts   # Cron jobs
+├── drizzle/                        # Migrations
+├── drizzle.config.ts
+├── package.json
+└── Dockerfile
+```
+
+## Datenbank-Schema
+
+### telegram_users
+
+Verknüpfung zwischen Telegram und ManaCore Accounts.
+
+| Column | Type | Description |
+|--------|------|-------------|
+| `id` | UUID | Primary key |
+| `telegram_user_id` | BIGINT | Telegram user ID (unique) |
+| `telegram_username` | TEXT | Telegram username |
+| `telegram_first_name` | TEXT | Telegram first name |
+| `mana_user_id` | TEXT | ManaCore user ID |
+| `access_token` | TEXT | JWT access token |
+| `refresh_token` | TEXT | JWT refresh token |
+| `token_expires_at` | TIMESTAMP | Token expiration |
+| `settings` | JSONB | User settings |
+| `is_active` | BOOLEAN | Active status |
+| `linked_at` | TIMESTAMP | Link timestamp |
+| `last_active_at` | TIMESTAMP | Last activity |
+| `created_at` | TIMESTAMP | Creation time |
+| `updated_at` | TIMESTAMP | Last update |
+
+### reminder_settings
+
+User-spezifische Erinnerungseinstellungen.
+
+| Column | Type | Description |
+|--------|------|-------------|
+| `id` | UUID | Primary key |
+| `telegram_user_id` | BIGINT | FK to telegram_users |
+| `default_reminder_minutes` | INTEGER | Default reminder time (15) |
+| `morning_briefing_enabled` | BOOLEAN | Enable daily briefing |
+| `morning_briefing_time` | TIME | Briefing time (07:00) |
+| `timezone` | TEXT | User timezone |
+| `notify_event_reminders` | BOOLEAN | Enable reminders |
+| `notify_event_changes` | BOOLEAN | Enable change notifications |
+| `notify_shared_calendars` | BOOLEAN | Enable share notifications |
+| `created_at` | TIMESTAMP | Creation time |
+| `updated_at` | TIMESTAMP | Last update |
+
+### sent_reminders
+
+Log of sent reminders to avoid duplicates.
+
+| Column | Type | Description |
+|--------|------|-------------|
+| `id` | UUID | Primary key |
+| `telegram_user_id` | BIGINT | FK to telegram_users |
+| `event_id` | TEXT | Calendar event ID |
+| `event_instance_date` | TIMESTAMP | For recurring events |
+| `reminder_type` | TEXT | 'before_event' or 'morning_briefing' |
+| `minutes_before` | INTEGER | Minutes before event |
+| `sent_at` | TIMESTAMP | Send timestamp |
+| `message_id` | INTEGER | Telegram message ID |
+
+## Lokale Entwicklung
+
+### 1. Bot bei Telegram erstellen
+
+1. Öffne @BotFather in Telegram
+2. Sende `/newbot`
+3. Wähle einen Namen (z.B. "ManaCore Calendar")
+4. Wähle einen Username (z.B. "manacore_calendar_bot")
+5. Kopiere den Token
+
+### 2. Umgebung vorbereiten
+
+```bash
+# Docker Services starten (PostgreSQL)
+pnpm docker:up
+
+# Datenbank erstellen
+psql -h localhost -U manacore -d postgres -c "CREATE DATABASE calendar_bot;"
+
+# In das Service-Verzeichnis wechseln
+cd services/telegram-calendar-bot
+
+# .env erstellen
+cp .env.example .env
+# Token und URLs eintragen
+
+# Schema pushen
+pnpm db:push
+```
+
+### 3. Bot starten
+
+```bash
+pnpm start:dev
+```
+
+### 4. Calendar Backend starten
+
+Der Bot benötigt das Calendar Backend:
+
+```bash
+# In einem anderen Terminal
+pnpm dev:calendar:backend
+```
+
+## Features
+
+### Termin-Abfragen
+
+- **Heute/Morgen/Woche**: Schnellübersicht der anstehenden Termine
+- **Nächste N**: Flexible Anzahl der nächsten Termine
+- **Kalender-Filter**: Termine nach Kalender filtern (TODO)
+
+### Erinnerungen
+
+- **Event-Reminder**: X Minuten vor einem Termin
+- **Morgen-Briefing**: Tägliche Zusammenfassung am Morgen
+- **Konfigurierbar**: Pro User anpassbar
+
+### Account-Verknüpfung
+
+- Telegram-User wird mit ManaCore-Account verknüpft
+- JWT-Token wird gespeichert für API-Zugriffe
+- Automatische Token-Refresh (TODO)
+
+## Scheduled Jobs
+
+| Job | Schedule | Beschreibung |
+|-----|----------|--------------|
+| `checkReminders` | Jede Minute | Prüft anstehende Events und sendet Erinnerungen |
+| `sendMorningBriefings` | Jede Stunde | Sendet Morgen-Briefing zur konfigurierten Zeit |
+| `cleanupOldReminders` | Täglich 03:00 | Löscht alte sent_reminders Einträge |
+
+## Health Check
+
+```bash
+curl http://localhost:3303/health
+```
+
+Antwort:
+```json
+{
+  "status": "ok",
+  "service": "telegram-calendar-bot",
+  "timestamp": "2025-01-27T10:00:00.000Z",
+  "environment": "development"
+}
+```
+
+## Deployment
+
+### Docker
+
+```yaml
+# docker-compose.yml
+telegram-calendar-bot:
+  build:
+    context: .
+    dockerfile: services/telegram-calendar-bot/Dockerfile
+  restart: always
+  environment:
+    PORT: 3303
+    TELEGRAM_BOT_TOKEN: ${TELEGRAM_CALENDAR_BOT_TOKEN}
+    CALENDAR_API_URL: http://calendar-backend:3016
+    DATABASE_URL: ${CALENDAR_BOT_DATABASE_URL}
+  ports:
+    - "3303:3303"
+```
+
+### Nativ
+
+```bash
+cd services/telegram-calendar-bot
+pnpm install
+pnpm build
+pnpm start:prod
+```
+
+## Roadmap
+
+- [ ] NLP für natürliche Spracheingabe ("/add Meeting morgen 14 Uhr")
+- [ ] OAuth-Flow für Account-Verknüpfung
+- [ ] Token-Refresh Mechanismus
+- [ ] Inline Keyboards für Interaktionen
+- [ ] Kalender-Filter bei Abfragen
+- [ ] Event-Erstellung mit allen Feldern
+- [ ] Recurring Event Support
+- [ ] Telegram Mini App Integration
diff --git a/services/telegram-calendar-bot/Dockerfile b/services/telegram-calendar-bot/Dockerfile
new file mode 100644
index 000000000..53906cbe9
--- /dev/null
+++ b/services/telegram-calendar-bot/Dockerfile
@@ -0,0 +1,45 @@
+FROM node:20-alpine AS builder
+
+WORKDIR /app
+
+# Install pnpm
+RUN corepack enable && corepack prepare pnpm@9.15.0 --activate
+
+# Copy package files
+COPY package.json pnpm-lock.yaml* ./
+COPY services/telegram-calendar-bot/package.json ./services/telegram-calendar-bot/
+
+# Install dependencies
+RUN pnpm install --frozen-lockfile --filter @manacore/telegram-calendar-bot
+
+# Copy source
+COPY services/telegram-calendar-bot ./services/telegram-calendar-bot
+
+# Build
+WORKDIR /app/services/telegram-calendar-bot
+RUN pnpm build
+
+# Production image
+FROM node:20-alpine AS runner
+
+WORKDIR /app
+
+# Install pnpm
+RUN corepack enable && corepack prepare pnpm@9.15.0 --activate
+
+# Copy built application
+COPY --from=builder /app/services/telegram-calendar-bot/dist ./dist
+COPY --from=builder /app/services/telegram-calendar-bot/package.json ./
+COPY --from=builder /app/services/telegram-calendar-bot/node_modules ./node_modules
+
+# Set environment
+ENV NODE_ENV=production
+ENV PORT=3303
+
+EXPOSE 3303
+
+# Health check
+HEALTHCHECK --interval=30s --timeout=10s --start-period=5s --retries=3 \
+  CMD wget --no-verbose --tries=1 --spider http://localhost:3303/health || exit 1
+
+CMD ["node", "dist/main.js"]
diff --git a/services/telegram-calendar-bot/drizzle.config.ts b/services/telegram-calendar-bot/drizzle.config.ts
new file mode 100644
index 000000000..1856e4499
--- /dev/null
+++ b/services/telegram-calendar-bot/drizzle.config.ts
@@ -0,0 +1,10 @@
+import { defineConfig } from 'drizzle-kit';
+
+export default defineConfig({
+	schema: './src/database/schema.ts',
+	out: './drizzle',
+	dialect: 'postgresql',
+	dbCredentials: {
+		url: process.env.DATABASE_URL || 'postgresql://manacore:devpassword@localhost:5432/calendar_bot',
+	},
+});
diff --git a/services/telegram-calendar-bot/nest-cli.json b/services/telegram-calendar-bot/nest-cli.json
new file mode 100644
index 000000000..95538fb90
--- /dev/null
+++ b/services/telegram-calendar-bot/nest-cli.json
@@ -0,0 +1,8 @@
+{
+	"$schema": "https://json.schemastore.org/nest-cli",
+	"collection": "@nestjs/schematics",
+	"sourceRoot": "src",
+	"compilerOptions": {
+		"deleteOutDir": true
+	}
+}
diff --git a/services/telegram-calendar-bot/package.json b/services/telegram-calendar-bot/package.json
new file mode 100644
index 000000000..c397b50ea
--- /dev/null
+++ b/services/telegram-calendar-bot/package.json
@@ -0,0 +1,44 @@
+{
+	"name": "@manacore/telegram-calendar-bot",
+	"version": "1.0.0",
+	"description": "Telegram bot for calendar events, reminders, and quick-add",
+	"private": true,
+	"license": "MIT",
+	"scripts": {
+		"prebuild": "rimraf dist",
+		"build": "nest build",
+		"format": "prettier --write \"src/**/*.ts\"",
+		"start": "nest start",
+		"start:dev": "nest start --watch",
+		"start:debug": "nest start --debug --watch",
+		"start:prod": "node dist/main",
+		"lint": "eslint \"{src,apps,libs,test}/**/*.ts\" --fix",
+		"type-check": "tsc --noEmit",
+		"db:generate": "drizzle-kit generate",
+		"db:push": "drizzle-kit push",
+		"db:studio": "drizzle-kit studio"
+	},
+	"dependencies": {
+		"@nestjs/common": "^10.4.15",
+		"@nestjs/config": "^10.0.0",
+		"@nestjs/core": "^10.4.15",
+		"@nestjs/platform-express": "^10.4.15",
+		"@nestjs/schedule": "^4.1.2",
+		"date-fns": "^4.1.0",
+		"date-fns-tz": "^3.2.0",
+		"drizzle-orm": "^0.38.3",
+		"nestjs-telegraf": "^2.8.0",
+		"postgres": "^3.4.5",
+		"reflect-metadata": "^0.2.2",
+		"rxjs": "^7.8.1",
+		"telegraf": "^4.16.3"
+	},
+	"devDependencies": {
+		"@nestjs/cli": "^10.4.9",
+		"@nestjs/schematics": "^10.2.3",
+		"@types/node": "^22.10.5",
+		"drizzle-kit": "^0.30.1",
+		"rimraf": "^6.0.1",
+		"typescript": "^5.7.3"
+	}
+}
diff --git a/services/telegram-calendar-bot/src/app.module.ts b/services/telegram-calendar-bot/src/app.module.ts
new file mode 100644
index 000000000..24816a5a6
--- /dev/null
+++ b/services/telegram-calendar-bot/src/app.module.ts
@@ -0,0 +1,29 @@
+import { Module } from '@nestjs/common';
+import { ConfigModule, ConfigService } from '@nestjs/config';
+import { TelegrafModule } from 'nestjs-telegraf';
+import configuration from './config/configuration';
+import { DatabaseModule } from './database/database.module';
+import { BotModule } from './bot/bot.module';
+import { ReminderModule } from './reminder/reminder.module';
+import { HealthController } from './health.controller';
+
+@Module({
+	imports: [
+		ConfigModule.forRoot({
+			isGlobal: true,
+			load: [configuration],
+		}),
+		TelegrafModule.forRootAsync({
+			imports: [ConfigModule],
+			useFactory: (configService: ConfigService) => ({
+				token: configService.get<string>('telegram.token') || '',
+			}),
+			inject: [ConfigService],
+		}),
+		DatabaseModule,
+		BotModule,
+		ReminderModule,
+	],
+	controllers: [HealthController],
+})
+export class AppModule {}
diff --git a/services/telegram-calendar-bot/src/bot/bot.module.ts b/services/telegram-calendar-bot/src/bot/bot.module.ts
new file mode 100644
index 000000000..3f709aab2
--- /dev/null
+++ b/services/telegram-calendar-bot/src/bot/bot.module.ts
@@ -0,0 +1,10 @@
+import { Module } from '@nestjs/common';
+import { BotUpdate } from './bot.update';
+import { CalendarModule } from '../calendar/calendar.module';
+import { UserModule } from '../user/user.module';
+
+@Module({
+	imports: [CalendarModule, UserModule],
+	providers: [BotUpdate],
+})
+export class BotModule {}
diff --git a/services/telegram-calendar-bot/src/bot/bot.update.ts b/services/telegram-calendar-bot/src/bot/bot.update.ts
new file mode 100644
index 000000000..801dcc4e2
--- /dev/null
+++ b/services/telegram-calendar-bot/src/bot/bot.update.ts
@@ -0,0 +1,332 @@
+import { Logger } from '@nestjs/common';
+import { Update, Ctx, Start, Help, Command, On, Message } from 'nestjs-telegraf';
+import { Context } from 'telegraf';
+import { ConfigService } from '@nestjs/config';
+import { CalendarClient } from '../calendar/calendar.client';
+import { UserService } from '../user/user.service';
+import {
+	formatHelpMessage,
+	formatTodayEvents,
+	formatTomorrowEvents,
+	formatWeekEvents,
+	formatNextEvents,
+	formatCalendars,
+	formatStatusMessage,
+} from './formatters';
+
+@Update()
+export class BotUpdate {
+	private readonly logger = new Logger(BotUpdate.name);
+	private readonly allowedUsers: number[];
+
+	constructor(
+		private readonly configService: ConfigService,
+		private readonly calendarClient: CalendarClient,
+		private readonly userService: UserService
+	) {
+		this.allowedUsers = this.configService.get<number[]>('telegram.allowedUsers') || [];
+	}
+
+	/**
+	 * Check if user is allowed (if restriction is enabled)
+	 */
+	private isAllowed(userId: number): boolean {
+		if (this.allowedUsers.length === 0) return true;
+		return this.allowedUsers.includes(userId);
+	}
+
+	/**
+	 * Get user's access token
+	 */
+	private async getAccessToken(telegramUserId: number): Promise<string | null> {
+		const user = await this.userService.getUserByTelegramId(telegramUserId);
+		if (!user || !user.isActive || !user.accessToken) {
+			return null;
+		}
+		return user.accessToken;
+	}
+
+	@Start()
+	async start(@Ctx() ctx: Context) {
+		const userId = ctx.from?.id;
+		this.logger.log(`/start from user ${userId}`);
+
+		if (!userId || !this.isAllowed(userId)) {
+			await ctx.reply('❌ Du bist nicht berechtigt, diesen Bot zu nutzen.');
+			return;
+		}
+
+		await ctx.replyWithHTML(formatHelpMessage());
+	}
+
+	@Help()
+	async help(@Ctx() ctx: Context) {
+		const userId = ctx.from?.id;
+		this.logger.log(`/help from user ${userId}`);
+
+		if (!userId || !this.isAllowed(userId)) {
+			return;
+		}
+
+		await ctx.replyWithHTML(formatHelpMessage());
+	}
+
+	@Command('today')
+	async today(@Ctx() ctx: Context) {
+		const userId = ctx.from?.id;
+		this.logger.log(`/today from user ${userId}`);
+
+		if (!userId || !this.isAllowed(userId)) {
+			return;
+		}
+
+		const accessToken = await this.getAccessToken(userId);
+		if (!accessToken) {
+			await ctx.reply('❌ Bitte verknüpfe zuerst deinen Account mit /link');
+			return;
+		}
+
+		await ctx.reply('📅 Lade heutige Termine...');
+		await this.userService.updateLastActive(userId);
+
+		const events = await this.calendarClient.getTodayEvents(accessToken);
+		await ctx.replyWithHTML(formatTodayEvents(events));
+	}
+
+	@Command('tomorrow')
+	async tomorrow(@Ctx() ctx: Context) {
+		const userId = ctx.from?.id;
+		this.logger.log(`/tomorrow from user ${userId}`);
+
+		if (!userId || !this.isAllowed(userId)) {
+			return;
+		}
+
+		const accessToken = await this.getAccessToken(userId);
+		if (!accessToken) {
+			await ctx.reply('❌ Bitte verknüpfe zuerst deinen Account mit /link');
+			return;
+		}
+
+		await ctx.reply('📅 Lade morgige Termine...');
+		await this.userService.updateLastActive(userId);
+
+		const events = await this.calendarClient.getTomorrowEvents(accessToken);
+		await ctx.replyWithHTML(formatTomorrowEvents(events));
+	}
+
+	@Command('week')
+	async week(@Ctx() ctx: Context) {
+		const userId = ctx.from?.id;
+		this.logger.log(`/week from user ${userId}`);
+
+		if (!userId || !this.isAllowed(userId)) {
+			return;
+		}
+
+		const accessToken = await this.getAccessToken(userId);
+		if (!accessToken) {
+			await ctx.reply('❌ Bitte verknüpfe zuerst deinen Account mit /link');
+			return;
+		}
+
+		await ctx.reply('📅 Lade Wochenübersicht...');
+		await this.userService.updateLastActive(userId);
+
+		const events = await this.calendarClient.getWeekEvents(accessToken);
+		await ctx.replyWithHTML(formatWeekEvents(events));
+	}
+
+	@Command('next')
+	async next(@Ctx() ctx: Context, @Message('text') text: string) {
+		const userId = ctx.from?.id;
+		this.logger.log(`/next from user ${userId}`);
+
+		if (!userId || !this.isAllowed(userId)) {
+			return;
+		}
+
+		const accessToken = await this.getAccessToken(userId);
+		if (!accessToken) {
+			await ctx.reply('❌ Bitte verknüpfe zuerst deinen Account mit /link');
+			return;
+		}
+
+		// Parse count from command
+		const parts = text.split(' ');
+		const count = parts.length > 1 ? parseInt(parts[1], 10) || 5 : 5;
+		const limitedCount = Math.min(Math.max(count, 1), 20);
+
+		await ctx.reply(`📅 Lade nächste ${limitedCount} Termine...`);
+		await this.userService.updateLastActive(userId);
+
+		const events = await this.calendarClient.getNextEvents(accessToken, limitedCount);
+		await ctx.replyWithHTML(formatNextEvents(events, limitedCount));
+	}
+
+	@Command('calendars')
+	async calendars(@Ctx() ctx: Context) {
+		const userId = ctx.from?.id;
+		this.logger.log(`/calendars from user ${userId}`);
+
+		if (!userId || !this.isAllowed(userId)) {
+			return;
+		}
+
+		const accessToken = await this.getAccessToken(userId);
+		if (!accessToken) {
+			await ctx.reply('❌ Bitte verknüpfe zuerst deinen Account mit /link');
+			return;
+		}
+
+		await this.userService.updateLastActive(userId);
+
+		const calendars = await this.calendarClient.getCalendars(accessToken);
+		await ctx.replyWithHTML(formatCalendars(calendars));
+	}
+
+	@Command('add')
+	async add(@Ctx() ctx: Context, @Message('text') text: string) {
+		const userId = ctx.from?.id;
+		this.logger.log(`/add from user ${userId}`);
+
+		if (!userId || !this.isAllowed(userId)) {
+			return;
+		}
+
+		const accessToken = await this.getAccessToken(userId);
+		if (!accessToken) {
+			await ctx.reply('❌ Bitte verknüpfe zuerst deinen Account mit /link');
+			return;
+		}
+
+		// Remove /add command from text
+		const input = text.replace(/^\/add\s*/i, '').trim();
+
+		if (!input) {
+			await ctx.replyWithHTML(`📝 <b>Termin erstellen</b>
+
+Beispiele:
+• /add Meeting morgen um 14 Uhr
+• /add Arzt | 20.01.2025 10:00 | 1h
+• /add Geburtstag Lisa | 15.03.2025 | ganztägig
+
+Format: /add [Titel] | [Datum Zeit] | [Dauer]`);
+			return;
+		}
+
+		// TODO: Implement NLP parsing
+		await ctx.reply(
+			`⚠️ Natürliche Spracheingabe wird noch implementiert.\n\nEmpfangener Text: "${input}"`
+		);
+	}
+
+	@Command('remind')
+	async remind(@Ctx() ctx: Context) {
+		const userId = ctx.from?.id;
+		this.logger.log(`/remind from user ${userId}`);
+
+		if (!userId || !this.isAllowed(userId)) {
+			return;
+		}
+
+		const user = await this.userService.getUserByTelegramId(userId);
+		if (!user) {
+			await ctx.reply('❌ Bitte verknüpfe zuerst deinen Account mit /link');
+			return;
+		}
+
+		const settings = await this.userService.getReminderSettings(userId);
+
+		await ctx.replyWithHTML(`⚙️ <b>Erinnerungseinstellungen</b>
+
+📢 Standard-Erinnerung: ${settings?.defaultReminderMinutes || 15} Minuten vorher
+🌅 Morgen-Briefing: ${settings?.morningBriefingEnabled ? `Aktiv (${settings.morningBriefingTime})` : 'Deaktiviert'}
+🌍 Zeitzone: ${settings?.timezone || 'Europe/Berlin'}
+
+<i>Einstellungen können in der Web-App geändert werden.</i>`);
+	}
+
+	@Command('status')
+	async status(@Ctx() ctx: Context) {
+		const userId = ctx.from?.id;
+		this.logger.log(`/status from user ${userId}`);
+
+		if (!userId || !this.isAllowed(userId)) {
+			return;
+		}
+
+		const user = await this.userService.getUserByTelegramId(userId);
+
+		await ctx.replyWithHTML(
+			formatStatusMessage(
+				!!user?.isActive && !!user?.accessToken,
+				user?.telegramUsername || user?.telegramFirstName,
+				user?.lastActiveAt || undefined
+			)
+		);
+	}
+
+	@Command('link')
+	async link(@Ctx() ctx: Context) {
+		const userId = ctx.from?.id;
+		this.logger.log(`/link from user ${userId}`);
+
+		if (!userId || !this.isAllowed(userId)) {
+			return;
+		}
+
+		// TODO: Implement proper OAuth flow or token-based linking
+		await ctx.replyWithHTML(`🔗 <b>Account verknüpfen</b>
+
+Um deinen ManaCore Account zu verknüpfen:
+
+1. Öffne die Calendar Web-App
+2. Gehe zu <b>Einstellungen → Integrationen → Telegram</b>
+3. Klicke auf "Mit Telegram verknüpfen"
+4. Gib deine Telegram User-ID ein: <code>${userId}</code>
+
+Nach der Verknüpfung kannst du alle Bot-Funktionen nutzen.`);
+	}
+
+	@Command('unlink')
+	async unlink(@Ctx() ctx: Context) {
+		const userId = ctx.from?.id;
+		this.logger.log(`/unlink from user ${userId}`);
+
+		if (!userId || !this.isAllowed(userId)) {
+			return;
+		}
+
+		const success = await this.userService.unlinkUser(userId);
+
+		if (success) {
+			await ctx.reply('✅ Account-Verknüpfung wurde aufgehoben.');
+		} else {
+			await ctx.reply('❌ Fehler beim Aufheben der Verknüpfung.');
+		}
+	}
+
+	@On('text')
+	async onText(@Ctx() ctx: Context, @Message('text') text: string) {
+		const userId = ctx.from?.id;
+
+		// Ignore commands
+		if (text.startsWith('/')) return;
+
+		if (!userId || !this.isAllowed(userId)) {
+			return;
+		}
+
+		// Check if user is linked
+		const accessToken = await this.getAccessToken(userId);
+		if (!accessToken) {
+			// Don't respond to random text from unlinked users
+			return;
+		}
+
+		// TODO: Implement NLP for natural language event creation
+		// For now, just acknowledge
+		this.logger.log(`Text message from ${userId}: ${text.substring(0, 50)}...`);
+	}
+}
diff --git a/services/telegram-calendar-bot/src/bot/formatters.ts b/services/telegram-calendar-bot/src/bot/formatters.ts
new file mode 100644
index 000000000..d8aec80b3
--- /dev/null
+++ b/services/telegram-calendar-bot/src/bot/formatters.ts
@@ -0,0 +1,412 @@
+import { format, isToday, isTomorrow, parseISO } from 'date-fns';
+import { de } from 'date-fns/locale';
+import { CalendarEvent, Calendar } from '../calendar/calendar.client';
+
+/**
+ * Format time from ISO string
+ */
+function formatTime(isoString: string): string {
+	return format(parseISO(isoString), 'HH:mm');
+}
+
+/**
+ * Format date from ISO string
+ */
+function formatDate(isoString: string): string {
+	const date = parseISO(isoString);
+	if (isToday(date)) return 'Heute';
+	if (isTomorrow(date)) return 'Morgen';
+	return format(date, 'EEE, d. MMM', { locale: de });
+}
+
+/**
+ * Format full date with weekday
+ */
+function formatFullDate(date: Date): string {
+	return format(date, 'EEEE, d. MMMM yyyy', { locale: de });
+}
+
+/**
+ * Get color emoji based on hex color
+ */
+function getColorEmoji(color?: string): string {
+	if (!color) return '📅';
+
+	const colorMap: Record<string, string> = {
+		'#3B82F6': '🔵', // blue
+		'#22C55E': '🟢', // green
+		'#EF4444': '🔴', // red
+		'#F59E0B': '🟡', // yellow/amber
+		'#8B5CF6': '🟣', // purple
+		'#EC4899': '💗', // pink
+		'#06B6D4': '🩵', // cyan
+		'#F97316': '🟠', // orange
+	};
+
+	// Try exact match
+	if (colorMap[color.toUpperCase()]) {
+		return colorMap[color.toUpperCase()];
+	}
+
+	// Default based on first character of hex
+	const firstChar = color.charAt(1).toLowerCase();
+	if (['0', '1', '2', '3'].includes(firstChar)) return '🔵';
+	if (['4', '5', '6', '7'].includes(firstChar)) return '🟢';
+	if (['8', '9', 'a', 'b'].includes(firstChar)) return '🟡';
+	return '🔴';
+}
+
+/**
+ * Format a single event
+ */
+export function formatEvent(event: CalendarEvent, showDate = false): string {
+	const emoji = getColorEmoji(event.color);
+	const timeRange = event.isAllDay
+		? 'Ganztägig'
+		: `${formatTime(event.startTime)} - ${formatTime(event.endTime)}`;
+
+	let text = `${emoji} <b>${timeRange}</b> | ${escapeHtml(event.title)}`;
+
+	if (showDate) {
+		text = `${emoji} <b>${formatDate(event.startTime)}</b> ${timeRange}\n   ${escapeHtml(event.title)}`;
+	}
+
+	if (event.location) {
+		text += `\n   📍 ${escapeHtml(event.location)}`;
+	}
+
+	if (event.description) {
+		const desc =
+			event.description.length > 50
+				? event.description.substring(0, 50) + '...'
+				: event.description;
+		text += `\n   📝 ${escapeHtml(desc)}`;
+	}
+
+	return text;
+}
+
+/**
+ * Format events list for a day
+ */
+export function formatDayEvents(events: CalendarEvent[], date: Date): string {
+	const header = `📅 <b>Termine für ${formatFullDate(date)}</b>\n`;
+
+	if (events.length === 0) {
+		return header + '\n✨ Keine Termine - genieße deinen freien Tag!';
+	}
+
+	// Sort by start time
+	const sorted = [...events].sort(
+		(a, b) => new Date(a.startTime).getTime() - new Date(b.startTime).getTime()
+	);
+
+	const eventsList = sorted.map((e) => formatEvent(e)).join('\n\n');
+
+	return `${header}\n${eventsList}\n\n───────────────\n${events.length} Termin${events.length === 1 ? '' : 'e'}`;
+}
+
+/**
+ * Format today's events
+ */
+export function formatTodayEvents(events: CalendarEvent[]): string {
+	const today = new Date();
+	const dayName = format(today, 'EEEE', { locale: de });
+	const header = `📅 <b>Deine Termine für heute</b> (${dayName}, ${format(today, 'd. MMMM', { locale: de })})\n`;
+
+	if (events.length === 0) {
+		return header + '\n✨ Keine Termine heute - genieße deinen freien Tag!';
+	}
+
+	const sorted = [...events].sort(
+		(a, b) => new Date(a.startTime).getTime() - new Date(b.startTime).getTime()
+	);
+
+	const eventsList = sorted.map((e) => formatEvent(e)).join('\n\n');
+
+	return `${header}\n${eventsList}\n\n───────────────\n${events.length} Termin${events.length === 1 ? '' : 'e'} heute`;
+}
+
+/**
+ * Format tomorrow's events
+ */
+export function formatTomorrowEvents(events: CalendarEvent[]): string {
+	const tomorrow = new Date();
+	tomorrow.setDate(tomorrow.getDate() + 1);
+	const dayName = format(tomorrow, 'EEEE', { locale: de });
+	const header = `📅 <b>Deine Termine für morgen</b> (${dayName}, ${format(tomorrow, 'd. MMMM', { locale: de })})\n`;
+
+	if (events.length === 0) {
+		return header + '\n✨ Keine Termine morgen!';
+	}
+
+	const sorted = [...events].sort(
+		(a, b) => new Date(a.startTime).getTime() - new Date(b.startTime).getTime()
+	);
+
+	const eventsList = sorted.map((e) => formatEvent(e)).join('\n\n');
+
+	return `${header}\n${eventsList}\n\n───────────────\n${events.length} Termin${events.length === 1 ? '' : 'e'} morgen`;
+}
+
+/**
+ * Format week overview
+ */
+export function formatWeekEvents(events: CalendarEvent[]): string {
+	const today = new Date();
+	const weekEnd = new Date(today);
+	weekEnd.setDate(weekEnd.getDate() + 7);
+
+	const header = `📅 <b>Deine Woche</b> (${format(today, 'd. MMM', { locale: de })} - ${format(weekEnd, 'd. MMM', { locale: de })})\n`;
+
+	if (events.length === 0) {
+		return header + '\n✨ Keine Termine diese Woche!';
+	}
+
+	// Group by day
+	const byDay = new Map<string, CalendarEvent[]>();
+	events.forEach((event) => {
+		const dayKey = format(parseISO(event.startTime), 'yyyy-MM-dd');
+		if (!byDay.has(dayKey)) {
+			byDay.set(dayKey, []);
+		}
+		byDay.get(dayKey)!.push(event);
+	});
+
+	// Sort days
+	const sortedDays = Array.from(byDay.keys()).sort();
+
+	let result = header + '\n';
+
+	for (const dayKey of sortedDays) {
+		const dayEvents = byDay.get(dayKey)!;
+		const dayDate = parseISO(dayKey);
+		const dayName = isToday(dayDate)
+			? '📍 Heute'
+			: isTomorrow(dayDate)
+				? '📍 Morgen'
+				: format(dayDate, 'EEE, d. MMM', { locale: de });
+
+		result += `<b>${dayName}</b>\n`;
+
+		const sorted = dayEvents.sort(
+			(a, b) => new Date(a.startTime).getTime() - new Date(b.startTime).getTime()
+		);
+
+		for (const event of sorted) {
+			const time = event.isAllDay ? '⏰' : formatTime(event.startTime);
+			result += `  ${getColorEmoji(event.color)} ${time} ${escapeHtml(event.title)}\n`;
+		}
+
+		result += '\n';
+	}
+
+	result += `───────────────\n${events.length} Termin${events.length === 1 ? '' : 'e'} diese Woche`;
+
+	return result;
+}
+
+/**
+ * Format next N events
+ */
+export function formatNextEvents(events: CalendarEvent[], count: number): string {
+	const header = `📅 <b>Deine nächsten ${count} Termine</b>\n`;
+
+	if (events.length === 0) {
+		return header + '\n✨ Keine anstehenden Termine!';
+	}
+
+	const eventsList = events.map((e) => formatEvent(e, true)).join('\n\n');
+
+	return `${header}\n${eventsList}`;
+}
+
+/**
+ * Format calendars list
+ */
+export function formatCalendars(calendars: Calendar[]): string {
+	if (calendars.length === 0) {
+		return '📅 <b>Deine Kalender</b>\n\nKeine Kalender gefunden.';
+	}
+
+	let result = '📅 <b>Deine Kalender</b>\n\n';
+
+	for (const cal of calendars) {
+		const emoji = getColorEmoji(cal.color);
+		const visibility = cal.isVisible ? '' : ' (versteckt)';
+		const isDefault = cal.isDefault ? ' ⭐' : '';
+		result += `${emoji} <b>${escapeHtml(cal.name)}</b>${isDefault}${visibility}\n`;
+		if (cal.description) {
+			result += `   ${escapeHtml(cal.description)}\n`;
+		}
+	}
+
+	return result;
+}
+
+/**
+ * Format event created confirmation
+ */
+export function formatEventCreated(event: CalendarEvent): string {
+	const emoji = getColorEmoji(event.color);
+	const date = formatDate(event.startTime);
+	const time = event.isAllDay
+		? 'Ganztägig'
+		: `${formatTime(event.startTime)} - ${formatTime(event.endTime)}`;
+
+	let result = `✅ <b>Termin erstellt!</b>\n\n`;
+	result += `${emoji} ${escapeHtml(event.title)}\n`;
+	result += `📅 ${date}, ${time}\n`;
+
+	if (event.location) {
+		result += `📍 ${escapeHtml(event.location)}\n`;
+	}
+
+	return result;
+}
+
+/**
+ * Format reminder notification
+ */
+export function formatReminder(event: CalendarEvent, minutesBefore: number): string {
+	const timeText =
+		minutesBefore >= 60
+			? `${Math.floor(minutesBefore / 60)} Stunde${minutesBefore >= 120 ? 'n' : ''}`
+			: `${minutesBefore} Minuten`;
+
+	let result = `⏰ <b>Erinnerung in ${timeText}</b>\n\n`;
+	result += `📌 <b>${escapeHtml(event.title)}</b>\n`;
+	result += `⏱️ ${formatTime(event.startTime)} - ${formatTime(event.endTime)}\n`;
+
+	if (event.location) {
+		result += `📍 ${escapeHtml(event.location)}\n`;
+	}
+
+	return result;
+}
+
+/**
+ * Format morning briefing
+ */
+export function formatMorningBriefing(events: CalendarEvent[]): string {
+	const today = new Date();
+	const greeting = getGreeting();
+
+	let result = `${greeting} ☀️\n\n`;
+	result += `<b>Dein Tag am ${format(today, 'd. MMMM', { locale: de })}</b>\n\n`;
+
+	if (events.length === 0) {
+		result += '✨ Keine Termine heute - genieße deinen freien Tag!';
+		return result;
+	}
+
+	const sorted = [...events].sort(
+		(a, b) => new Date(a.startTime).getTime() - new Date(b.startTime).getTime()
+	);
+
+	for (const event of sorted) {
+		const emoji = getColorEmoji(event.color);
+		const time = event.isAllDay ? 'Ganztägig' : formatTime(event.startTime);
+		result += `${emoji} <b>${time}</b> - ${escapeHtml(event.title)}\n`;
+	}
+
+	result += `\n───────────────\n${events.length} Termin${events.length === 1 ? '' : 'e'} heute`;
+
+	return result;
+}
+
+/**
+ * Format help message
+ */
+export function formatHelpMessage(): string {
+	return `🗓️ <b>Calendar Bot - Hilfe</b>
+
+<b>Termine anzeigen:</b>
+/today - Heutige Termine
+/tomorrow - Morgige Termine
+/week - Wochenübersicht
+/next [n] - Nächste n Termine
+
+<b>Termine erstellen:</b>
+/add Meeting morgen um 14 Uhr
+/add Arzt | 20.01.2025 10:00 | 1h
+
+<b>Kalender:</b>
+/calendars - Kalender-Übersicht
+
+<b>Einstellungen:</b>
+/remind - Erinnerungseinstellungen
+/status - Verbindungsstatus
+
+<b>Account:</b>
+/link - ManaCore Account verknüpfen
+/unlink - Verknüpfung trennen
+
+───────────────
+💡 Du kannst auch einfach Text senden, um schnell einen Termin zu erstellen!`;
+}
+
+/**
+ * Format status message
+ */
+export function formatStatusMessage(
+	isLinked: boolean,
+	username?: string,
+	lastActive?: Date
+): string {
+	if (!isLinked) {
+		return `📊 <b>Status</b>
+
+❌ Nicht mit ManaCore verknüpft
+
+Nutze /link um deinen Account zu verknüpfen.`;
+	}
+
+	const lastActiveText = lastActive ? format(lastActive, 'd. MMM HH:mm', { locale: de }) : 'Nie';
+
+	return `📊 <b>Status</b>
+
+✅ Verknüpft mit ManaCore
+👤 ${username || 'Unbekannt'}
+🕐 Letzte Aktivität: ${lastActiveText}
+
+Nutze /unlink um die Verknüpfung zu trennen.`;
+}
+
+/**
+ * Format link instructions
+ */
+export function formatLinkInstructions(linkToken: string): string {
+	return `🔗 <b>Account verknüpfen</b>
+
+Um deinen ManaCore Account zu verknüpfen:
+
+1. Öffne die Calendar Web App
+2. Gehe zu Einstellungen → Telegram
+3. Gib diesen Code ein:
+
+<code>${linkToken}</code>
+
+Der Code ist 10 Minuten gültig.`;
+}
+
+/**
+ * Get time-appropriate greeting
+ */
+function getGreeting(): string {
+	const hour = new Date().getHours();
+	if (hour < 12) return 'Guten Morgen';
+	if (hour < 18) return 'Guten Tag';
+	return 'Guten Abend';
+}
+
+/**
+ * Escape HTML special characters
+ */
+function escapeHtml(text: string): string {
+	return text
+		.replace(/&/g, '&amp;')
+		.replace(/</g, '&lt;')
+		.replace(/>/g, '&gt;')
+		.replace(/"/g, '&quot;');
+}
diff --git a/services/telegram-calendar-bot/src/calendar/calendar.client.ts b/services/telegram-calendar-bot/src/calendar/calendar.client.ts
new file mode 100644
index 000000000..8a1bc96c8
--- /dev/null
+++ b/services/telegram-calendar-bot/src/calendar/calendar.client.ts
@@ -0,0 +1,216 @@
+import { Injectable, Logger } from '@nestjs/common';
+import { ConfigService } from '@nestjs/config';
+
+export interface Calendar {
+	id: string;
+	userId: string;
+	name: string;
+	description?: string;
+	color: string;
+	isDefault: boolean;
+	isVisible: boolean;
+	timezone?: string;
+}
+
+export interface CalendarEvent {
+	id: string;
+	calendarId: string;
+	userId: string;
+	title: string;
+	description?: string;
+	location?: string;
+	startTime: string;
+	endTime: string;
+	isAllDay: boolean;
+	timezone?: string;
+	recurrenceRule?: string;
+	color?: string;
+	status: 'confirmed' | 'tentative' | 'cancelled';
+}
+
+export interface CreateEventDto {
+	calendarId: string;
+	title: string;
+	description?: string;
+	location?: string;
+	startTime: string;
+	endTime: string;
+	isAllDay?: boolean;
+	timezone?: string;
+}
+
+@Injectable()
+export class CalendarClient {
+	private readonly logger = new Logger(CalendarClient.name);
+	private readonly apiUrl: string;
+
+	constructor(private configService: ConfigService) {
+		this.apiUrl = this.configService.get<string>('calendar.apiUrl') || 'http://localhost:3016';
+	}
+
+	private async request<T>(
+		endpoint: string,
+		accessToken: string,
+		options: RequestInit = {}
+	): Promise<T | null> {
+		const url = `${this.apiUrl}${endpoint}`;
+
+		try {
+			const response = await fetch(url, {
+				...options,
+				headers: {
+					'Content-Type': 'application/json',
+					Authorization: `Bearer ${accessToken}`,
+					...options.headers,
+				},
+			});
+
+			if (!response.ok) {
+				this.logger.error(`API request failed: ${response.status} ${response.statusText}`);
+				return null;
+			}
+
+			return (await response.json()) as T;
+		} catch (error) {
+			this.logger.error(`API request error: ${error}`);
+			return null;
+		}
+	}
+
+	/**
+	 * Get all calendars for the user
+	 */
+	async getCalendars(accessToken: string): Promise<Calendar[]> {
+		const result = await this.request<Calendar[]>('/api/v1/calendars', accessToken);
+		return result || [];
+	}
+
+	/**
+	 * Get events for a date range
+	 */
+	async getEvents(
+		accessToken: string,
+		start: Date,
+		end: Date,
+		calendarId?: string
+	): Promise<CalendarEvent[]> {
+		const params = new URLSearchParams({
+			start: start.toISOString(),
+			end: end.toISOString(),
+		});
+
+		if (calendarId) {
+			params.append('calendarId', calendarId);
+		}
+
+		const result = await this.request<CalendarEvent[]>(
+			`/api/v1/events?${params.toString()}`,
+			accessToken
+		);
+		return result || [];
+	}
+
+	/**
+	 * Get today's events
+	 */
+	async getTodayEvents(accessToken: string, timezone = 'Europe/Berlin'): Promise<CalendarEvent[]> {
+		const now = new Date();
+		const start = new Date(now.getFullYear(), now.getMonth(), now.getDate());
+		const end = new Date(start);
+		end.setDate(end.getDate() + 1);
+
+		return this.getEvents(accessToken, start, end);
+	}
+
+	/**
+	 * Get tomorrow's events
+	 */
+	async getTomorrowEvents(
+		accessToken: string,
+		timezone = 'Europe/Berlin'
+	): Promise<CalendarEvent[]> {
+		const now = new Date();
+		const start = new Date(now.getFullYear(), now.getMonth(), now.getDate() + 1);
+		const end = new Date(start);
+		end.setDate(end.getDate() + 1);
+
+		return this.getEvents(accessToken, start, end);
+	}
+
+	/**
+	 * Get this week's events
+	 */
+	async getWeekEvents(accessToken: string, timezone = 'Europe/Berlin'): Promise<CalendarEvent[]> {
+		const now = new Date();
+		const start = new Date(now.getFullYear(), now.getMonth(), now.getDate());
+		const end = new Date(start);
+		end.setDate(end.getDate() + 7);
+
+		return this.getEvents(accessToken, start, end);
+	}
+
+	/**
+	 * Get next N events
+	 */
+	async getNextEvents(accessToken: string, count = 5): Promise<CalendarEvent[]> {
+		const now = new Date();
+		const end = new Date(now);
+		end.setMonth(end.getMonth() + 3); // Look 3 months ahead
+
+		const events = await this.getEvents(accessToken, now, end);
+
+		// Sort by start time and take first N
+		return events
+			.filter((e) => new Date(e.startTime) >= now)
+			.sort((a, b) => new Date(a.startTime).getTime() - new Date(b.startTime).getTime())
+			.slice(0, count);
+	}
+
+	/**
+	 * Get upcoming events for reminders (within next X minutes)
+	 */
+	async getUpcomingEventsForReminders(
+		accessToken: string,
+		withinMinutes: number
+	): Promise<CalendarEvent[]> {
+		const now = new Date();
+		const end = new Date(now.getTime() + withinMinutes * 60 * 1000);
+
+		return this.getEvents(accessToken, now, end);
+	}
+
+	/**
+	 * Create a new event
+	 */
+	async createEvent(accessToken: string, event: CreateEventDto): Promise<CalendarEvent | null> {
+		return this.request<CalendarEvent>('/api/v1/events', accessToken, {
+			method: 'POST',
+			body: JSON.stringify(event),
+		});
+	}
+
+	/**
+	 * Get a single event by ID
+	 */
+	async getEvent(accessToken: string, eventId: string): Promise<CalendarEvent | null> {
+		return this.request<CalendarEvent>(`/api/v1/events/${eventId}`, accessToken);
+	}
+
+	/**
+	 * Delete an event
+	 */
+	async deleteEvent(accessToken: string, eventId: string): Promise<boolean> {
+		try {
+			const response = await fetch(`${this.apiUrl}/api/v1/events/${eventId}`, {
+				method: 'DELETE',
+				headers: {
+					Authorization: `Bearer ${accessToken}`,
+				},
+			});
+			return response.ok;
+		} catch (error) {
+			this.logger.error(`Delete event error: ${error}`);
+			return false;
+		}
+	}
+}
diff --git a/services/telegram-calendar-bot/src/calendar/calendar.module.ts b/services/telegram-calendar-bot/src/calendar/calendar.module.ts
new file mode 100644
index 000000000..8be5311d5
--- /dev/null
+++ b/services/telegram-calendar-bot/src/calendar/calendar.module.ts
@@ -0,0 +1,8 @@
+import { Module } from '@nestjs/common';
+import { CalendarClient } from './calendar.client';
+
+@Module({
+	providers: [CalendarClient],
+	exports: [CalendarClient],
+})
+export class CalendarModule {}
diff --git a/services/telegram-calendar-bot/src/config/configuration.ts b/services/telegram-calendar-bot/src/config/configuration.ts
new file mode 100644
index 000000000..c93ab778d
--- /dev/null
+++ b/services/telegram-calendar-bot/src/config/configuration.ts
@@ -0,0 +1,48 @@
+export default () => ({
+	port: parseInt(process.env.PORT || '3303', 10),
+	nodeEnv: process.env.NODE_ENV || 'development',
+
+	telegram: {
+		token: process.env.TELEGRAM_BOT_TOKEN || '',
+		allowedUsers: process.env.TELEGRAM_ALLOWED_USERS
+			? process.env.TELEGRAM_ALLOWED_USERS.split(',').map((id) => parseInt(id.trim(), 10))
+			: [],
+	},
+
+	calendar: {
+		apiUrl: process.env.CALENDAR_API_URL || 'http://localhost:3016',
+		authUrl: process.env.MANA_CORE_AUTH_URL || 'http://localhost:3001',
+	},
+
+	database: {
+		url: process.env.DATABASE_URL,
+	},
+
+	reminder: {
+		checkInterval: parseInt(process.env.REMINDER_CHECK_INTERVAL || '60000', 10),
+		morningBriefing: {
+			enabled: process.env.MORNING_BRIEFING_ENABLED === 'true',
+			time: process.env.MORNING_BRIEFING_TIME || '07:00',
+			timezone: process.env.MORNING_BRIEFING_TIMEZONE || 'Europe/Berlin',
+		},
+	},
+});
+
+// Command descriptions for BotFather
+export const COMMANDS = [
+	{ command: 'start', description: 'Hilfe & Account verknüpfen' },
+	{ command: 'help', description: 'Verfügbare Befehle anzeigen' },
+	{ command: 'today', description: 'Heutige Termine' },
+	{ command: 'tomorrow', description: 'Morgige Termine' },
+	{ command: 'week', description: 'Wochenübersicht' },
+	{ command: 'next', description: 'Nächste Termine (z.B. /next 5)' },
+	{ command: 'add', description: 'Termin hinzufügen' },
+	{ command: 'calendars', description: 'Kalender-Übersicht' },
+	{ command: 'remind', description: 'Erinnerungseinstellungen' },
+	{ command: 'link', description: 'ManaCore Account verknüpfen' },
+	{ command: 'unlink', description: 'Account-Verknüpfung trennen' },
+	{ command: 'status', description: 'Verbindungsstatus prüfen' },
+];
+
+// Default reminder times (minutes before event)
+export const DEFAULT_REMINDER_OPTIONS = [5, 10, 15, 30, 60, 120, 1440]; // 1440 = 1 day
diff --git a/services/telegram-calendar-bot/src/database/database.module.ts b/services/telegram-calendar-bot/src/database/database.module.ts
new file mode 100644
index 000000000..abe5e0258
--- /dev/null
+++ b/services/telegram-calendar-bot/src/database/database.module.ts
@@ -0,0 +1,40 @@
+import { Module, Global, Logger } from '@nestjs/common';
+import { ConfigService } from '@nestjs/config';
+import { drizzle, PostgresJsDatabase } from 'drizzle-orm/postgres-js';
+import postgres from 'postgres';
+import * as schema from './schema';
+
+export const DATABASE_CONNECTION = 'DATABASE_CONNECTION';
+
+@Global()
+@Module({
+	providers: [
+		{
+			provide: DATABASE_CONNECTION,
+			inject: [ConfigService],
+			useFactory: (configService: ConfigService) => {
+				const logger = new Logger('Database');
+				const databaseUrl = configService.get<string>('database.url');
+
+				if (!databaseUrl) {
+					logger.warn('DATABASE_URL not configured - database features disabled');
+					return null;
+				}
+
+				try {
+					const client = postgres(databaseUrl);
+					const db = drizzle(client, { schema });
+					logger.log('Database connection established');
+					return db;
+				} catch (error) {
+					logger.error('Failed to connect to database:', error);
+					return null;
+				}
+			},
+		},
+	],
+	exports: [DATABASE_CONNECTION],
+})
+export class DatabaseModule {}
+
+export type Database = PostgresJsDatabase<typeof schema>;
diff --git a/services/telegram-calendar-bot/src/database/schema.ts b/services/telegram-calendar-bot/src/database/schema.ts
new file mode 100644
index 000000000..f9bfb66b9
--- /dev/null
+++ b/services/telegram-calendar-bot/src/database/schema.ts
@@ -0,0 +1,150 @@
+import {
+	pgTable,
+	uuid,
+	text,
+	timestamp,
+	bigint,
+	boolean,
+	integer,
+	time,
+	jsonb,
+	index,
+} from 'drizzle-orm/pg-core';
+import { relations } from 'drizzle-orm';
+
+/**
+ * User settings stored in JSONB
+ */
+export interface UserSettings {
+	language?: 'de' | 'en';
+	defaultCalendarId?: string;
+	quietHoursStart?: string; // HH:mm
+	quietHoursEnd?: string; // HH:mm
+}
+
+/**
+ * Telegram users linked to ManaCore accounts
+ */
+export const telegramUsers = pgTable(
+	'telegram_users',
+	{
+		id: uuid('id').primaryKey().defaultRandom(),
+		telegramUserId: bigint('telegram_user_id', { mode: 'number' }).unique().notNull(),
+		telegramUsername: text('telegram_username'),
+		telegramFirstName: text('telegram_first_name'),
+
+		// ManaCore account link
+		manaUserId: text('mana_user_id').notNull(),
+		accessToken: text('access_token'),
+		refreshToken: text('refresh_token'),
+		tokenExpiresAt: timestamp('token_expires_at', { withTimezone: true }),
+
+		// Settings
+		settings: jsonb('settings').$type<UserSettings>().default({}),
+		isActive: boolean('is_active').default(true).notNull(),
+
+		// Timestamps
+		linkedAt: timestamp('linked_at', { withTimezone: true }).defaultNow().notNull(),
+		lastActiveAt: timestamp('last_active_at', { withTimezone: true }),
+		createdAt: timestamp('created_at', { withTimezone: true }).defaultNow().notNull(),
+		updatedAt: timestamp('updated_at', { withTimezone: true }).defaultNow().notNull(),
+	},
+	(table) => ({
+		telegramUserIdx: index('telegram_users_telegram_id_idx').on(table.telegramUserId),
+		manaUserIdx: index('telegram_users_mana_id_idx').on(table.manaUserId),
+	})
+);
+
+/**
+ * Reminder settings per user
+ */
+export const reminderSettings = pgTable(
+	'reminder_settings',
+	{
+		id: uuid('id').primaryKey().defaultRandom(),
+		telegramUserId: bigint('telegram_user_id', { mode: 'number' })
+			.references(() => telegramUsers.telegramUserId, { onDelete: 'cascade' })
+			.notNull(),
+
+		// Default reminder timing
+		defaultReminderMinutes: integer('default_reminder_minutes').default(15).notNull(),
+
+		// Morning briefing
+		morningBriefingEnabled: boolean('morning_briefing_enabled').default(false).notNull(),
+		morningBriefingTime: time('morning_briefing_time').default('07:00').notNull(),
+
+		// Timezone
+		timezone: text('timezone').default('Europe/Berlin').notNull(),
+
+		// Notification preferences
+		notifyEventReminders: boolean('notify_event_reminders').default(true).notNull(),
+		notifyEventChanges: boolean('notify_event_changes').default(true).notNull(),
+		notifySharedCalendars: boolean('notify_shared_calendars').default(true).notNull(),
+
+		createdAt: timestamp('created_at', { withTimezone: true }).defaultNow().notNull(),
+		updatedAt: timestamp('updated_at', { withTimezone: true }).defaultNow().notNull(),
+	},
+	(table) => ({
+		userIdx: index('reminder_settings_user_idx').on(table.telegramUserId),
+	})
+);
+
+/**
+ * Sent reminders log (to avoid duplicates)
+ */
+export const sentReminders = pgTable(
+	'sent_reminders',
+	{
+		id: uuid('id').primaryKey().defaultRandom(),
+		telegramUserId: bigint('telegram_user_id', { mode: 'number' })
+			.references(() => telegramUsers.telegramUserId, { onDelete: 'cascade' })
+			.notNull(),
+
+		// Event reference
+		eventId: text('event_id').notNull(),
+		eventInstanceDate: timestamp('event_instance_date', { withTimezone: true }),
+
+		// Reminder details
+		reminderType: text('reminder_type').notNull(), // 'before_event' | 'morning_briefing'
+		minutesBefore: integer('minutes_before'),
+
+		// Status
+		sentAt: timestamp('sent_at', { withTimezone: true }).defaultNow().notNull(),
+		messageId: integer('message_id'), // Telegram message ID
+	},
+	(table) => ({
+		userEventIdx: index('sent_reminders_user_event_idx').on(table.telegramUserId, table.eventId),
+		sentAtIdx: index('sent_reminders_sent_at_idx').on(table.sentAt),
+	})
+);
+
+// Relations
+export const telegramUsersRelations = relations(telegramUsers, ({ one, many }) => ({
+	reminderSettings: one(reminderSettings, {
+		fields: [telegramUsers.telegramUserId],
+		references: [reminderSettings.telegramUserId],
+	}),
+	sentReminders: many(sentReminders),
+}));
+
+export const reminderSettingsRelations = relations(reminderSettings, ({ one }) => ({
+	user: one(telegramUsers, {
+		fields: [reminderSettings.telegramUserId],
+		references: [telegramUsers.telegramUserId],
+	}),
+}));
+
+export const sentRemindersRelations = relations(sentReminders, ({ one }) => ({
+	user: one(telegramUsers, {
+		fields: [sentReminders.telegramUserId],
+		references: [telegramUsers.telegramUserId],
+	}),
+}));
+
+// Types
+export type TelegramUser = typeof telegramUsers.$inferSelect;
+export type NewTelegramUser = typeof telegramUsers.$inferInsert;
+export type ReminderSetting = typeof reminderSettings.$inferSelect;
+export type NewReminderSetting = typeof reminderSettings.$inferInsert;
+export type SentReminder = typeof sentReminders.$inferSelect;
+export type NewSentReminder = typeof sentReminders.$inferInsert;
diff --git a/services/telegram-calendar-bot/src/health.controller.ts b/services/telegram-calendar-bot/src/health.controller.ts
new file mode 100644
index 000000000..eefcfc168
--- /dev/null
+++ b/services/telegram-calendar-bot/src/health.controller.ts
@@ -0,0 +1,17 @@
+import { Controller, Get } from '@nestjs/common';
+import { ConfigService } from '@nestjs/config';
+
+@Controller('health')
+export class HealthController {
+	constructor(private configService: ConfigService) {}
+
+	@Get()
+	health() {
+		return {
+			status: 'ok',
+			service: 'telegram-calendar-bot',
+			timestamp: new Date().toISOString(),
+			environment: this.configService.get<string>('nodeEnv'),
+		};
+	}
+}
diff --git a/services/telegram-calendar-bot/src/main.ts b/services/telegram-calendar-bot/src/main.ts
new file mode 100644
index 000000000..d02fac2fd
--- /dev/null
+++ b/services/telegram-calendar-bot/src/main.ts
@@ -0,0 +1,21 @@
+import { NestFactory } from '@nestjs/core';
+import { Logger } from '@nestjs/common';
+import { ConfigService } from '@nestjs/config';
+import { AppModule } from './app.module';
+
+async function bootstrap() {
+	const logger = new Logger('Bootstrap');
+	const app = await NestFactory.create(AppModule);
+
+	const configService = app.get(ConfigService);
+	const port = configService.get<number>('port') || 3303;
+
+	// Graceful shutdown
+	app.enableShutdownHooks();
+
+	await app.listen(port);
+	logger.log(`Telegram Calendar Bot running on port ${port}`);
+	logger.log(`Calendar API: ${configService.get<string>('calendar.apiUrl')}`);
+}
+
+bootstrap();
diff --git a/services/telegram-calendar-bot/src/reminder/reminder.module.ts b/services/telegram-calendar-bot/src/reminder/reminder.module.ts
new file mode 100644
index 000000000..7534dcb39
--- /dev/null
+++ b/services/telegram-calendar-bot/src/reminder/reminder.module.ts
@@ -0,0 +1,13 @@
+import { Module } from '@nestjs/common';
+import { ScheduleModule } from '@nestjs/schedule';
+import { ReminderScheduler } from './reminder.scheduler';
+import { ReminderService } from './reminder.service';
+import { CalendarModule } from '../calendar/calendar.module';
+import { UserModule } from '../user/user.module';
+
+@Module({
+	imports: [ScheduleModule.forRoot(), CalendarModule, UserModule],
+	providers: [ReminderScheduler, ReminderService],
+	exports: [ReminderService],
+})
+export class ReminderModule {}
diff --git a/services/telegram-calendar-bot/src/reminder/reminder.scheduler.ts b/services/telegram-calendar-bot/src/reminder/reminder.scheduler.ts
new file mode 100644
index 000000000..e37c8867c
--- /dev/null
+++ b/services/telegram-calendar-bot/src/reminder/reminder.scheduler.ts
@@ -0,0 +1,183 @@
+import { Injectable, Logger } from '@nestjs/common';
+import { Cron, CronExpression } from '@nestjs/schedule';
+import { ConfigService } from '@nestjs/config';
+import { InjectBot } from 'nestjs-telegraf';
+import { Telegraf, Context } from 'telegraf';
+import { CalendarClient } from '../calendar/calendar.client';
+import { UserService } from '../user/user.service';
+import { ReminderService } from './reminder.service';
+import { formatReminder, formatMorningBriefing } from '../bot/formatters';
+
+@Injectable()
+export class ReminderScheduler {
+	private readonly logger = new Logger(ReminderScheduler.name);
+
+	constructor(
+		@InjectBot() private bot: Telegraf<Context>,
+		private configService: ConfigService,
+		private calendarClient: CalendarClient,
+		private userService: UserService,
+		private reminderService: ReminderService
+	) {}
+
+	/**
+	 * Check for upcoming events and send reminders
+	 * Runs every minute
+	 */
+	@Cron(CronExpression.EVERY_MINUTE)
+	async checkReminders() {
+		this.logger.debug('Checking for event reminders...');
+
+		try {
+			const users = await this.userService.getAllActiveUsers();
+
+			for (const user of users) {
+				if (!user.accessToken) continue;
+
+				const settings = await this.userService.getReminderSettings(user.telegramUserId);
+				if (!settings?.notifyEventReminders) continue;
+
+				const reminderMinutes = settings.defaultReminderMinutes || 15;
+
+				// Get events starting in the next reminderMinutes
+				const events = await this.calendarClient.getUpcomingEventsForReminders(
+					user.accessToken,
+					reminderMinutes + 1 // Add 1 minute buffer
+				);
+
+				for (const event of events) {
+					const eventStart = new Date(event.startTime);
+					const now = new Date();
+					const minutesUntilEvent = Math.floor(
+						(eventStart.getTime() - now.getTime()) / (1000 * 60)
+					);
+
+					// Check if this is the right time to send reminder
+					if (minutesUntilEvent <= reminderMinutes && minutesUntilEvent > reminderMinutes - 1) {
+						// Check if we already sent this reminder
+						const alreadySent = await this.reminderService.wasReminderSent(
+							user.telegramUserId,
+							event.id,
+							'before_event',
+							reminderMinutes
+						);
+
+						if (!alreadySent) {
+							await this.sendReminder(user.telegramUserId, event, reminderMinutes);
+						}
+					}
+				}
+			}
+		} catch (error) {
+			this.logger.error(`Error checking reminders: ${error}`);
+		}
+	}
+
+	/**
+	 * Send morning briefing
+	 * Runs at 7:00 AM (configurable via morning briefing time per user)
+	 */
+	@Cron('0 * * * *') // Run every hour, check user-specific times
+	async sendMorningBriefings() {
+		this.logger.debug('Checking for morning briefings...');
+
+		try {
+			const usersWithBriefing = await this.userService.getUsersWithMorningBriefing();
+			const now = new Date();
+			const currentHour = now.getHours();
+			const currentMinute = now.getMinutes();
+
+			for (const { user, settings } of usersWithBriefing) {
+				if (!user.accessToken) continue;
+
+				// Parse briefing time (HH:mm format)
+				const [briefingHour, briefingMinute] = (settings.morningBriefingTime || '07:00')
+					.split(':')
+					.map(Number);
+
+				// Check if it's the right hour (minute check is less precise due to cron)
+				if (currentHour === briefingHour && currentMinute < 5) {
+					// Check if we already sent today's briefing
+					const today = new Date().toISOString().split('T')[0];
+					const alreadySent = await this.reminderService.wasReminderSent(
+						user.telegramUserId,
+						`briefing-${today}`,
+						'morning_briefing'
+					);
+
+					if (!alreadySent) {
+						await this.sendBriefing(user.telegramUserId, user.accessToken);
+					}
+				}
+			}
+		} catch (error) {
+			this.logger.error(`Error sending morning briefings: ${error}`);
+		}
+	}
+
+	/**
+	 * Cleanup old sent reminders
+	 * Runs daily at 3:00 AM
+	 */
+	@Cron('0 3 * * *')
+	async cleanupOldReminders() {
+		this.logger.log('Cleaning up old sent reminders...');
+		await this.reminderService.cleanupOldReminders();
+	}
+
+	/**
+	 * Send a reminder notification
+	 */
+	private async sendReminder(
+		telegramUserId: number,
+		event: { id: string; title: string; startTime: string; endTime: string; location?: string; color?: string },
+		minutesBefore: number
+	) {
+		try {
+			const message = formatReminder(event as any, minutesBefore);
+			const sent = await this.bot.telegram.sendMessage(telegramUserId, message, {
+				parse_mode: 'HTML',
+			});
+
+			// Record that we sent this reminder
+			await this.reminderService.recordSentReminder({
+				telegramUserId,
+				eventId: event.id,
+				reminderType: 'before_event',
+				minutesBefore,
+				messageId: sent.message_id,
+			});
+
+			this.logger.log(`Sent reminder to ${telegramUserId} for event ${event.id}`);
+		} catch (error) {
+			this.logger.error(`Error sending reminder to ${telegramUserId}: ${error}`);
+		}
+	}
+
+	/**
+	 * Send morning briefing
+	 */
+	private async sendBriefing(telegramUserId: number, accessToken: string) {
+		try {
+			const events = await this.calendarClient.getTodayEvents(accessToken);
+			const message = formatMorningBriefing(events);
+
+			const sent = await this.bot.telegram.sendMessage(telegramUserId, message, {
+				parse_mode: 'HTML',
+			});
+
+			// Record that we sent today's briefing
+			const today = new Date().toISOString().split('T')[0];
+			await this.reminderService.recordSentReminder({
+				telegramUserId,
+				eventId: `briefing-${today}`,
+				reminderType: 'morning_briefing',
+				messageId: sent.message_id,
+			});
+
+			this.logger.log(`Sent morning briefing to ${telegramUserId}`);
+		} catch (error) {
+			this.logger.error(`Error sending briefing to ${telegramUserId}: ${error}`);
+		}
+	}
+}
diff --git a/services/telegram-calendar-bot/src/reminder/reminder.service.ts b/services/telegram-calendar-bot/src/reminder/reminder.service.ts
new file mode 100644
index 000000000..50aa00a37
--- /dev/null
+++ b/services/telegram-calendar-bot/src/reminder/reminder.service.ts
@@ -0,0 +1,101 @@
+import { Injectable, Inject, Logger } from '@nestjs/common';
+import { eq, and, gte, lte } from 'drizzle-orm';
+import { DATABASE_CONNECTION, Database } from '../database/database.module';
+import { sentReminders, NewSentReminder, SentReminder } from '../database/schema';
+
+@Injectable()
+export class ReminderService {
+	private readonly logger = new Logger(ReminderService.name);
+
+	constructor(@Inject(DATABASE_CONNECTION) private db: Database | null) {}
+
+	/**
+	 * Check if a reminder was already sent
+	 */
+	async wasReminderSent(
+		telegramUserId: number,
+		eventId: string,
+		reminderType: string,
+		minutesBefore?: number,
+		eventInstanceDate?: Date
+	): Promise<boolean> {
+		if (!this.db) return false;
+
+		try {
+			// Look for sent reminders in the last 24 hours to avoid duplicates
+			const oneDayAgo = new Date(Date.now() - 24 * 60 * 60 * 1000);
+
+			const result = await this.db
+				.select()
+				.from(sentReminders)
+				.where(
+					and(
+						eq(sentReminders.telegramUserId, telegramUserId),
+						eq(sentReminders.eventId, eventId),
+						eq(sentReminders.reminderType, reminderType),
+						gte(sentReminders.sentAt, oneDayAgo)
+					)
+				)
+				.limit(1);
+
+			return result.length > 0;
+		} catch (error) {
+			this.logger.error(`Error checking sent reminder: ${error}`);
+			return false;
+		}
+	}
+
+	/**
+	 * Record a sent reminder
+	 */
+	async recordSentReminder(data: {
+		telegramUserId: number;
+		eventId: string;
+		reminderType: string;
+		minutesBefore?: number;
+		eventInstanceDate?: Date;
+		messageId?: number;
+	}): Promise<SentReminder | null> {
+		if (!this.db) return null;
+
+		try {
+			const newReminder: NewSentReminder = {
+				telegramUserId: data.telegramUserId,
+				eventId: data.eventId,
+				reminderType: data.reminderType,
+				minutesBefore: data.minutesBefore,
+				eventInstanceDate: data.eventInstanceDate,
+				messageId: data.messageId,
+			};
+
+			const result = await this.db.insert(sentReminders).values(newReminder).returning();
+
+			return result[0] || null;
+		} catch (error) {
+			this.logger.error(`Error recording sent reminder: ${error}`);
+			return null;
+		}
+	}
+
+	/**
+	 * Clean up old sent reminders (older than 7 days)
+	 */
+	async cleanupOldReminders(): Promise<number> {
+		if (!this.db) return 0;
+
+		try {
+			const sevenDaysAgo = new Date(Date.now() - 7 * 24 * 60 * 60 * 1000);
+
+			const result = await this.db
+				.delete(sentReminders)
+				.where(lte(sentReminders.sentAt, sevenDaysAgo));
+
+			// Drizzle doesn't return count directly, so we estimate
+			this.logger.log('Cleaned up old sent reminders');
+			return 0;
+		} catch (error) {
+			this.logger.error(`Error cleaning up old reminders: ${error}`);
+			return 0;
+		}
+	}
+}
diff --git a/services/telegram-calendar-bot/src/user/user.module.ts b/services/telegram-calendar-bot/src/user/user.module.ts
new file mode 100644
index 000000000..ab6ead25c
--- /dev/null
+++ b/services/telegram-calendar-bot/src/user/user.module.ts
@@ -0,0 +1,8 @@
+import { Module } from '@nestjs/common';
+import { UserService } from './user.service';
+
+@Module({
+	providers: [UserService],
+	exports: [UserService],
+})
+export class UserModule {}
diff --git a/services/telegram-calendar-bot/src/user/user.service.ts b/services/telegram-calendar-bot/src/user/user.service.ts
new file mode 100644
index 000000000..f298623b8
--- /dev/null
+++ b/services/telegram-calendar-bot/src/user/user.service.ts
@@ -0,0 +1,240 @@
+import { Injectable, Inject, Logger } from '@nestjs/common';
+import { eq } from 'drizzle-orm';
+import { DATABASE_CONNECTION, Database } from '../database/database.module';
+import {
+	telegramUsers,
+	reminderSettings,
+	TelegramUser,
+	NewTelegramUser,
+	ReminderSetting,
+} from '../database/schema';
+
+@Injectable()
+export class UserService {
+	private readonly logger = new Logger(UserService.name);
+
+	constructor(@Inject(DATABASE_CONNECTION) private db: Database | null) {}
+
+	/**
+	 * Get user by Telegram ID
+	 */
+	async getUserByTelegramId(telegramUserId: number): Promise<TelegramUser | null> {
+		if (!this.db) return null;
+
+		try {
+			const result = await this.db
+				.select()
+				.from(telegramUsers)
+				.where(eq(telegramUsers.telegramUserId, telegramUserId))
+				.limit(1);
+
+			return result[0] || null;
+		} catch (error) {
+			this.logger.error(`Error getting user: ${error}`);
+			return null;
+		}
+	}
+
+	/**
+	 * Create or update a linked user
+	 */
+	async linkUser(data: {
+		telegramUserId: number;
+		telegramUsername?: string;
+		telegramFirstName?: string;
+		manaUserId: string;
+		accessToken: string;
+		refreshToken?: string;
+		tokenExpiresAt?: Date;
+	}): Promise<TelegramUser | null> {
+		if (!this.db) return null;
+
+		try {
+			const existing = await this.getUserByTelegramId(data.telegramUserId);
+
+			if (existing) {
+				// Update existing
+				const result = await this.db
+					.update(telegramUsers)
+					.set({
+						telegramUsername: data.telegramUsername,
+						telegramFirstName: data.telegramFirstName,
+						manaUserId: data.manaUserId,
+						accessToken: data.accessToken,
+						refreshToken: data.refreshToken,
+						tokenExpiresAt: data.tokenExpiresAt,
+						isActive: true,
+						updatedAt: new Date(),
+					})
+					.where(eq(telegramUsers.telegramUserId, data.telegramUserId))
+					.returning();
+
+				return result[0] || null;
+			} else {
+				// Create new
+				const newUser: NewTelegramUser = {
+					telegramUserId: data.telegramUserId,
+					telegramUsername: data.telegramUsername,
+					telegramFirstName: data.telegramFirstName,
+					manaUserId: data.manaUserId,
+					accessToken: data.accessToken,
+					refreshToken: data.refreshToken,
+					tokenExpiresAt: data.tokenExpiresAt,
+				};
+
+				const result = await this.db.insert(telegramUsers).values(newUser).returning();
+
+				// Create default reminder settings
+				if (result[0]) {
+					await this.db.insert(reminderSettings).values({
+						telegramUserId: data.telegramUserId,
+					});
+				}
+
+				return result[0] || null;
+			}
+		} catch (error) {
+			this.logger.error(`Error linking user: ${error}`);
+			return null;
+		}
+	}
+
+	/**
+	 * Unlink a user (deactivate)
+	 */
+	async unlinkUser(telegramUserId: number): Promise<boolean> {
+		if (!this.db) return false;
+
+		try {
+			await this.db
+				.update(telegramUsers)
+				.set({
+					isActive: false,
+					accessToken: null,
+					refreshToken: null,
+					updatedAt: new Date(),
+				})
+				.where(eq(telegramUsers.telegramUserId, telegramUserId));
+
+			return true;
+		} catch (error) {
+			this.logger.error(`Error unlinking user: ${error}`);
+			return false;
+		}
+	}
+
+	/**
+	 * Update last active timestamp
+	 */
+	async updateLastActive(telegramUserId: number): Promise<void> {
+		if (!this.db) return;
+
+		try {
+			await this.db
+				.update(telegramUsers)
+				.set({ lastActiveAt: new Date() })
+				.where(eq(telegramUsers.telegramUserId, telegramUserId));
+		} catch (error) {
+			this.logger.error(`Error updating last active: ${error}`);
+		}
+	}
+
+	/**
+	 * Get reminder settings for a user
+	 */
+	async getReminderSettings(telegramUserId: number): Promise<ReminderSetting | null> {
+		if (!this.db) return null;
+
+		try {
+			const result = await this.db
+				.select()
+				.from(reminderSettings)
+				.where(eq(reminderSettings.telegramUserId, telegramUserId))
+				.limit(1);
+
+			return result[0] || null;
+		} catch (error) {
+			this.logger.error(`Error getting reminder settings: ${error}`);
+			return null;
+		}
+	}
+
+	/**
+	 * Update reminder settings
+	 */
+	async updateReminderSettings(
+		telegramUserId: number,
+		settings: Partial<{
+			defaultReminderMinutes: number;
+			morningBriefingEnabled: boolean;
+			morningBriefingTime: string;
+			timezone: string;
+			notifyEventReminders: boolean;
+			notifyEventChanges: boolean;
+			notifySharedCalendars: boolean;
+		}>
+	): Promise<ReminderSetting | null> {
+		if (!this.db) return null;
+
+		try {
+			const result = await this.db
+				.update(reminderSettings)
+				.set({
+					...settings,
+					updatedAt: new Date(),
+				})
+				.where(eq(reminderSettings.telegramUserId, telegramUserId))
+				.returning();
+
+			return result[0] || null;
+		} catch (error) {
+			this.logger.error(`Error updating reminder settings: ${error}`);
+			return null;
+		}
+	}
+
+	/**
+	 * Get all active users (for reminder scheduler)
+	 */
+	async getAllActiveUsers(): Promise<TelegramUser[]> {
+		if (!this.db) return [];
+
+		try {
+			return await this.db
+				.select()
+				.from(telegramUsers)
+				.where(eq(telegramUsers.isActive, true));
+		} catch (error) {
+			this.logger.error(`Error getting active users: ${error}`);
+			return [];
+		}
+	}
+
+	/**
+	 * Get users with morning briefing enabled
+	 */
+	async getUsersWithMorningBriefing(): Promise<
+		Array<{ user: TelegramUser; settings: ReminderSetting }>
+	> {
+		if (!this.db) return [];
+
+		try {
+			const result = await this.db
+				.select({
+					user: telegramUsers,
+					settings: reminderSettings,
+				})
+				.from(telegramUsers)
+				.innerJoin(
+					reminderSettings,
+					eq(telegramUsers.telegramUserId, reminderSettings.telegramUserId)
+				)
+				.where(eq(telegramUsers.isActive, true));
+
+			return result.filter((r) => r.settings.morningBriefingEnabled);
+		} catch (error) {
+			this.logger.error(`Error getting users with morning briefing: ${error}`);
+			return [];
+		}
+	}
+}
diff --git a/services/telegram-calendar-bot/tsconfig.json b/services/telegram-calendar-bot/tsconfig.json
new file mode 100644
index 000000000..94f1e9493
--- /dev/null
+++ b/services/telegram-calendar-bot/tsconfig.json
@@ -0,0 +1,22 @@
+{
+	"compilerOptions": {
+		"module": "commonjs",
+		"declaration": true,
+		"removeComments": true,
+		"emitDecoratorMetadata": true,
+		"experimentalDecorators": true,
+		"allowSyntheticDefaultImports": true,
+		"target": "ES2021",
+		"sourceMap": true,
+		"outDir": "./dist",
+		"baseUrl": "./",
+		"incremental": true,
+		"skipLibCheck": true,
+		"strictNullChecks": true,
+		"noImplicitAny": false,
+		"strictBindCallApply": false,
+		"forceConsistentCasingInFileNames": false,
+		"noFallthroughCasesInSwitch": false,
+		"esModuleInterop": true
+	}
+}