diff --git a/TENANT_LIMITS_IMPLEMENTATION.md b/TENANT_LIMITS_IMPLEMENTATION.md
new file mode 100644
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--- /dev/null
+++ b/TENANT_LIMITS_IMPLEMENTATION.md
@@ -0,0 +1,277 @@
+# Tenant Limits Implementation
+
+## Overview
+
+This document explains how tenant subscription limits are enforced in the UAM-ILS Drone Detection System. All the issues you identified have been resolved:
+
+## ✅ Issues Fixed
+
+### 1. **User Creation Limits**
+- **Problem**: Tenants could create unlimited users regardless of their subscription limits
+- **Solution**: Added `enforceUserLimit()` middleware to `POST /tenant/users`
+- **Implementation**: Counts existing users and validates against `tenant.features.max_users`
+
+### 2. **Device Creation Limits** 
+- **Problem**: Tenants could add unlimited devices regardless of their subscription limits
+- **Solution**: Added `enforceDeviceLimit()` middleware to `POST /devices`
+- **Implementation**: Counts existing devices and validates against `tenant.features.max_devices`
+
+### 3. **API Rate Limiting**
+- **Problem**: No proper API rate limiting per tenant shared among users
+- **Solution**: Implemented `enforceApiRateLimit()` middleware
+- **Implementation**: 
+  - Tracks actual API requests (not page views)
+  - Rate limit is shared among ALL users in a tenant
+  - Uses sliding window algorithm
+  - Applied to all authenticated API endpoints
+
+### 4. **Data Retention**
+- **Problem**: Old data was never cleaned up automatically
+- **Solution**: Created `DataRetentionService` with cron job
+- **Implementation**:
+  - Runs daily at 2:00 AM UTC
+  - Deletes detections, heartbeats, and logs older than `tenant.features.data_retention_days`
+  - Respects unlimited retention (`-1` value)
+  - Provides preview endpoint to see what would be deleted
+
+## 🔧 Technical Implementation
+
+### Middleware: `server/middleware/tenant-limits.js`
+
+```javascript
+// User limit enforcement
+enforceUserLimit() - Prevents user creation when limit reached
+enforceDeviceLimit() - Prevents device creation when limit reached  
+enforceApiRateLimit() - Rate limits API requests per tenant
+getTenantLimitsStatus() - Returns current usage vs limits
+```
+
+### Service: `server/services/dataRetention.js`
+
+```javascript
+DataRetentionService {
+  start() - Starts daily cron job
+  performCleanup() - Cleans all tenants based on retention policies
+  previewCleanup(tenantId) - Shows what would be deleted
+  getStats() - Returns cleanup statistics
+}
+```
+
+### API Endpoints
+
+```bash
+GET /api/tenant/limits
+# Returns current usage and limits for the tenant
+{
+  "users": { "current": 3, "limit": 5, "unlimited": false },
+  "devices": { "current": 7, "limit": 10, "unlimited": false },
+  "api_requests": { "current_minute": 45, "limit_per_minute": 1000 },
+  "data_retention": { "days": 90, "unlimited": false }
+}
+
+GET /api/tenant/data-retention/preview
+# Shows what data would be deleted by retention cleanup
+{
+  "tenantSlug": "tenant1",
+  "retentionDays": 90,
+  "cutoffDate": "2024-06-24T02:00:00.000Z",
+  "toDelete": {
+    "detections": 1250,
+    "heartbeats": 4500,
+    "logs": 89
+  }
+}
+```
+
+## 🚦 How Rate Limiting Works
+
+### API Rate Limiting Details
+- **Granularity**: Per tenant (shared among all users)
+- **Window**: 1 minute sliding window
+- **Storage**: In-memory with automatic cleanup
+- **Headers**: Standard rate limit headers included
+- **Tracking**: Only actual API requests count (not static files/page views)
+
+### Example Rate Limit Response
+```json
+{
+  "success": false,
+  "message": "API rate limit exceeded. Maximum 1000 requests per 60 seconds for your tenant.",
+  "error_code": "TENANT_API_RATE_LIMIT_EXCEEDED",
+  "max_requests": 1000,
+  "window_seconds": 60,
+  "retry_after_seconds": 15
+}
+```
+
+## 📊 Subscription Tiers
+
+The system supports different subscription tiers with these default limits:
+
+```javascript
+// Free tier
+{
+  max_devices: 2,
+  max_users: 1,
+  api_rate_limit: 100,
+  data_retention_days: 7
+}
+
+// Pro tier  
+{
+  max_devices: 10,
+  max_users: 5,
+  api_rate_limit: 1000,
+  data_retention_days: 90
+}
+
+// Business tier
+{
+  max_devices: 50,
+  max_users: 20,
+  api_rate_limit: 5000,
+  data_retention_days: 365
+}
+
+// Enterprise tier
+{
+  max_devices: -1,    // Unlimited
+  max_users: -1,      // Unlimited  
+  api_rate_limit: -1, // Unlimited
+  data_retention_days: -1 // Unlimited
+}
+```
+
+## 🔒 Security Features
+
+### Limit Enforcement Security
+- All limit checks are done server-side (cannot be bypassed)
+- Security events are logged when limits are exceeded
+- Failed attempts include IP address, user agent, and user details
+- Graceful error messages prevent information disclosure
+
+### Error Response Format
+```json
+{
+  "success": false,
+  "message": "Tenant has reached the maximum number of users (5). Please upgrade your subscription or remove existing users.",
+  "error_code": "TENANT_USER_LIMIT_EXCEEDED",
+  "current_count": 5,
+  "max_allowed": 5
+}
+```
+
+## 🕒 Data Retention Schedule
+
+### Cleanup Process
+1. **Trigger**: Daily at 2:00 AM UTC via cron job
+2. **Process**: For each active tenant:
+   - Check `tenant.features.data_retention_days`
+   - Skip if unlimited (`-1`)
+   - Calculate cutoff date
+   - Delete old detections, heartbeats, logs
+   - Log security events for significant cleanups
+3. **Performance**: Batched operations with error handling per tenant
+
+### Manual Operations
+```javascript
+// Preview what would be deleted
+const service = new DataRetentionService();
+const preview = await service.previewCleanup(tenantId);
+
+// Manually trigger cleanup (admin only)
+await service.triggerManualCleanup();
+
+// Get cleanup statistics
+const stats = service.getStats();
+```
+
+## 🔧 Docker Integration
+
+### Package Dependencies
+Added to `server/package.json`:
+```json
+{
+  "dependencies": {
+    "node-cron": "^3.0.2"
+  }
+}
+```
+
+### Service Initialization
+All services start automatically when the Docker container boots:
+```javascript
+// In server/index.js
+const dataRetentionService = new DataRetentionService();
+dataRetentionService.start();
+console.log('🗂️  Data retention service: ✅ Started');
+```
+
+## 🧪 Testing the Implementation
+
+### Test User Limits
+```bash
+# Create users until limit is reached
+curl -X POST /api/tenant/users \
+  -H "Authorization: Bearer $TOKEN" \
+  -d '{"username":"test6","email":"test6@example.com","password":"password"}'
+
+# Should return 403 when limit exceeded
+```
+
+### Test Device Limits
+```bash
+# Create devices until limit is reached  
+curl -X POST /api/devices \
+  -H "Authorization: Bearer $TOKEN" \
+  -d '{"id":"device-11","name":"Test Device 11"}'
+
+# Should return 403 when limit exceeded
+```
+
+### Test API Rate Limits
+```bash
+# Send rapid requests to trigger rate limit
+for i in {1..1100}; do
+  curl -X GET /api/detections -H "Authorization: Bearer $TOKEN" &
+done
+
+# Should return 429 after limit reached
+```
+
+### Test Data Retention
+```bash
+# Preview what would be deleted
+curl -X GET /api/tenant/data-retention/preview \
+  -H "Authorization: Bearer $TOKEN"
+
+# Check tenant limits status
+curl -X GET /api/tenant/limits \
+  -H "Authorization: Bearer $TOKEN"
+```
+
+## 📈 Monitoring & Logging
+
+### Security Logs
+All limit violations are logged with full context:
+- User ID and username
+- Tenant ID and slug  
+- IP address and user agent
+- Specific limit exceeded and current usage
+- Timestamp and action details
+
+### Performance Monitoring
+- Rate limit middleware tracks response times
+- Data retention service logs cleanup duration and counts
+- Memory usage monitoring for rate limit store
+- Database query performance for limit checks
+
+## 🔄 Upgrade Path
+
+When tenants upgrade their subscription:
+1. Update `tenant.features` with new limits
+2. Limits take effect immediately
+3. No restart required
+4. Historical data respects new retention policy on next cleanup
+
+This comprehensive implementation ensures that tenant limits are properly enforced across all aspects of the system, preventing abuse while providing clear feedback to users about their subscription status.
\ No newline at end of file
diff --git a/data-retention-service/.env.example b/data-retention-service/.env.example
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+# Data Retention Service Environment Variables
+
+# Database Configuration
+DB_HOST=postgres
+DB_PORT=5432
+DB_NAME=drone_detection
+DB_USER=postgres
+DB_PASSWORD=your_secure_password
+
+# Service Configuration
+NODE_ENV=production
+
+# Set to 'true' to run cleanup immediately on startup (useful for testing)
+IMMEDIATE_CLEANUP=false
+
+# Logging level
+LOG_LEVEL=info
\ No newline at end of file
diff --git a/data-retention-service/Dockerfile b/data-retention-service/Dockerfile
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+++ b/data-retention-service/Dockerfile
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+# Data Retention Service
+
+FROM node:18-alpine
+
+# Create app directory
+WORKDIR /app
+
+# Copy package files
+COPY package*.json ./
+
+# Install only production dependencies
+RUN npm ci --only=production
+
+# Copy source code
+COPY . .
+
+# Create non-root user
+RUN addgroup -g 1001 -S nodejs
+RUN adduser -S retention -u 1001
+
+# Change ownership
+RUN chown -R retention:nodejs /app
+USER retention
+
+# Health check
+HEALTHCHECK --interval=30s --timeout=10s --start-period=5s --retries=3 \
+  CMD node healthcheck.js
+
+# Start the service
+CMD ["node", "index.js"]
\ No newline at end of file
diff --git a/data-retention-service/README.md b/data-retention-service/README.md
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+++ b/data-retention-service/README.md
@@ -0,0 +1,312 @@
+# Data Retention Service
+
+A lightweight, standalone microservice responsible for automated data cleanup based on tenant retention policies.
+
+## Overview
+
+This service runs as a separate Docker container and performs the following functions:
+
+- **Automated Cleanup**: Daily scheduled cleanup at 2:00 AM UTC
+- **Tenant-Aware**: Respects individual tenant retention policies
+- **Lightweight**: Minimal resource footprint (~64-128MB RAM)
+- **Resilient**: Continues operation even if individual tenant cleanups fail
+- **Logged**: Comprehensive logging and health monitoring
+
+## Architecture
+
+```
+┌─────────────────┐    ┌─────────────────┐    ┌─────────────────┐
+│   Main Backend  │    │  Data Retention │    │   PostgreSQL    │
+│    Container    │    │     Service     │    │    Database     │
+│                 │    │                 │    │                 │
+│ • API Endpoints │    │ • Cron Jobs     │◄──►│ • tenant data   │
+│ • Business Logic│    │ • Data Cleanup  │    │ • detections    │
+│ • Rate Limiting │    │ • Health Check  │    │ • heartbeats    │
+└─────────────────┘    └─────────────────┘    └─────────────────┘
+```
+
+## Features
+
+### 🕒 Scheduled Operations
+- Runs daily at 2:00 AM UTC via cron job
+- Configurable immediate cleanup for development/testing
+- Graceful shutdown handling
+
+### 🏢 Multi-Tenant Support
+- Processes all active tenants
+- Respects individual retention policies:
+  - `-1` = Unlimited retention (no cleanup)
+  - `N` = Delete data older than N days
+  - Default: 90 days if not specified
+
+### 🧹 Data Cleanup
+- **Drone Detections**: Historical detection records
+- **Heartbeats**: Device connectivity logs  
+- **Security Logs**: Audit trail entries (if applicable)
+
+### 📊 Monitoring & Health
+- Built-in health checks for Docker
+- Memory usage monitoring
+- Cleanup statistics tracking
+- Error logging with tenant context
+
+## Configuration
+
+### Environment Variables
+
+```bash
+# Database Connection
+DB_HOST=postgres          # Database host
+DB_PORT=5432             # Database port  
+DB_NAME=drone_detection  # Database name
+DB_USER=postgres         # Database user
+DB_PASSWORD=password     # Database password
+
+# Service Settings
+NODE_ENV=production      # Environment mode
+IMMEDIATE_CLEANUP=false  # Run cleanup on startup
+LOG_LEVEL=info          # Logging level
+```
+
+### Docker Compose Integration
+
+```yaml
+data-retention:
+  build:
+    context: ./data-retention-service
+  container_name: drone-detection-data-retention
+  restart: unless-stopped
+  environment:
+    DB_HOST: postgres
+    DB_PORT: 5432
+    DB_NAME: drone_detection
+    DB_USER: postgres
+    DB_PASSWORD: your_secure_password
+  depends_on:
+    postgres:
+      condition: service_healthy
+  deploy:
+    resources:
+      limits:
+        memory: 128M
+```
+
+## Usage
+
+### Start with Docker Compose
+
+```bash
+# Start all services including data retention
+docker-compose up -d
+
+# Start only data retention service
+docker-compose up -d data-retention
+
+# View logs
+docker-compose logs -f data-retention
+```
+
+### Manual Container Build
+
+```bash
+# Build the container
+cd data-retention-service
+docker build -t data-retention-service .
+
+# Run the container
+docker run -d \
+  --name data-retention \
+  --env-file .env \
+  --network drone-network \
+  data-retention-service
+```
+
+### Development Mode
+
+```bash
+# Install dependencies
+npm install
+
+# Run with immediate cleanup
+IMMEDIATE_CLEANUP=true npm start
+
+# Run in development mode
+npm run dev
+```
+
+## Logging Output
+
+### Startup
+```
+🗂️  Starting Data Retention Service...
+📅 Environment: production
+💾 Database: postgres:5432/drone_detection
+✅ Database connection established
+⏰ Scheduled cleanup: Daily at 2:00 AM UTC
+✅ Data Retention Service started successfully
+```
+
+### Cleanup Operation
+```
+🧹 Starting data retention cleanup...
+⏰ Cleanup started at: 2024-09-23T02:00:00.123Z
+🏢 Found 5 active tenants to process
+🧹 Cleaning tenant acme-corp - removing data older than 90 days
+✅ Tenant acme-corp: Deleted 1250 detections, 4500 heartbeats, 89 logs
+⏭️  Skipping tenant enterprise-unlimited - unlimited retention
+✅ Data retention cleanup completed
+⏱️  Duration: 2347ms
+📊 Deleted: 2100 detections, 8900 heartbeats, 156 logs
+```
+
+### Health Monitoring
+```
+💚 Health Check - Uptime: 3600s, Memory: 45MB, Last Cleanup: 2024-09-23T02:00:00.123Z
+```
+
+## API Integration
+
+The main backend provides endpoints to interact with retention policies:
+
+```bash
+# Get current tenant limits and retention info
+GET /api/tenant/limits
+
+# Preview what would be deleted
+GET /api/tenant/data-retention/preview
+```
+
+## Error Handling
+
+### Tenant-Level Errors
+- Service continues if individual tenant cleanup fails
+- Errors logged with tenant context
+- Failed tenants skipped, others processed normally
+
+### Service-Level Errors  
+- Database connection issues cause service restart
+- Health checks detect and report issues
+- Graceful shutdown on container stop signals
+
+### Example Error Log
+```
+❌ Error cleaning tenant problematic-tenant: SequelizeTimeoutError: Query timeout
+⚠️  Errors encountered: 1
+   - problematic-tenant: Query timeout
+```
+
+## Performance
+
+### Resource Usage
+- **Memory**: 64-128MB typical usage
+- **CPU**: Minimal, only during cleanup operations
+- **Storage**: Logs rotate automatically
+- **Network**: Database queries only
+
+### Cleanup Performance
+- Batch operations for efficiency
+- Indexed database queries on timestamp fields
+- Parallel tenant processing where possible
+- Configurable batch sizes for large datasets
+
+## Security
+
+### Database Access
+- Read/write access only to required tables
+- Connection pooling with limits
+- Prepared statements prevent SQL injection
+
+### Container Security  
+- Non-root user execution
+- Minimal base image (node:18-alpine)
+- No exposed ports
+- Isolated network access
+
+## Monitoring
+
+### Health Checks
+```bash
+# Docker health check
+docker exec data-retention node healthcheck.js
+
+# Container status
+docker-compose ps data-retention
+
+# Service logs  
+docker-compose logs -f data-retention
+```
+
+### Metrics
+- Cleanup duration and frequency
+- Records deleted per tenant
+- Memory usage over time
+- Error rates and types
+
+## Troubleshooting
+
+### Common Issues
+
+**Service won't start**
+```bash
+# Check database connectivity
+docker-compose logs postgres
+docker-compose logs data-retention
+
+# Verify environment variables
+docker-compose config
+```
+
+**Cleanup not running**
+```bash
+# Check cron schedule
+docker exec data-retention ps aux | grep cron
+
+# Force immediate cleanup
+docker exec data-retention node -e "
+const service = require('./index.js');
+service.performCleanup();
+"
+```
+
+**High memory usage**
+```bash
+# Check cleanup frequency
+docker stats data-retention
+
+# Review tenant data volumes
+docker exec data-retention node -e "
+const { getModels } = require('./database');
+// Check tenant data sizes
+"
+```
+
+### Configuration Validation
+
+```bash
+# Test database connection
+docker exec data-retention node healthcheck.js
+
+# Verify tenant policies
+docker exec -it data-retention node -e "
+const { getModels } = require('./database');
+(async () => {
+  const { Tenant } = await getModels();
+  const tenants = await Tenant.findAll();
+  console.log(tenants.map(t => ({
+    slug: t.slug,
+    retention: t.features?.data_retention_days
+  })));
+})();
+"
+```
+
+## Migration from Integrated Service
+
+If upgrading from a version where data retention was part of the main backend:
+
+1. **Deploy new container**: Add data retention service to docker-compose.yml
+2. **Verify operation**: Check logs for successful startup and database connection
+3. **Remove old code**: The integrated service code is automatically disabled
+4. **Monitor transition**: Ensure cleanup operations continue normally
+
+The service is designed to be backward compatible and will work with existing tenant configurations without changes.
\ No newline at end of file
diff --git a/data-retention-service/database.js b/data-retention-service/database.js
new file mode 100644
index 0000000..6bf2459
--- /dev/null
+++ b/data-retention-service/database.js
@@ -0,0 +1,222 @@
+/**
+ * Database connection and models for Data Retention Service
+ */
+
+const { Sequelize, DataTypes } = require('sequelize');
+
+let sequelize;
+let models = {};
+
+/**
+ * Initialize database connection
+ */
+async function initializeDatabase() {
+  // Database connection
+  sequelize = new Sequelize(
+    process.env.DB_NAME || 'drone_detection',
+    process.env.DB_USER || 'postgres',
+    process.env.DB_PASSWORD || 'password',
+    {
+      host: process.env.DB_HOST || 'localhost',
+      port: process.env.DB_PORT || 5432,
+      dialect: 'postgres',
+      logging: process.env.NODE_ENV === 'development' ? console.log : false,
+      pool: {
+        max: 5,
+        min: 0,
+        acquire: 30000,
+        idle: 10000
+      }
+    }
+  );
+
+  // Test connection
+  await sequelize.authenticate();
+  
+  // Define models
+  defineModels();
+  
+  return sequelize;
+}
+
+/**
+ * Define database models
+ */
+function defineModels() {
+  // Tenant model
+  models.Tenant = sequelize.define('Tenant', {
+    id: {
+      type: DataTypes.INTEGER,
+      primaryKey: true,
+      autoIncrement: true
+    },
+    slug: {
+      type: DataTypes.STRING(50),
+      unique: true,
+      allowNull: false
+    },
+    name: {
+      type: DataTypes.STRING(100),
+      allowNull: false
+    },
+    features: {
+      type: DataTypes.JSONB,
+      defaultValue: {}
+    },
+    is_active: {
+      type: DataTypes.BOOLEAN,
+      defaultValue: true
+    }
+  }, {
+    tableName: 'tenants',
+    timestamps: true,
+    createdAt: 'created_at',
+    updatedAt: 'updated_at'
+  });
+
+  // DroneDetection model
+  models.DroneDetection = sequelize.define('DroneDetection', {
+    id: {
+      type: DataTypes.INTEGER,
+      primaryKey: true,
+      autoIncrement: true
+    },
+    tenant_id: {
+      type: DataTypes.INTEGER,
+      allowNull: false
+    },
+    device_id: {
+      type: DataTypes.STRING(50),
+      allowNull: false
+    },
+    timestamp: {
+      type: DataTypes.DATE,
+      allowNull: false
+    },
+    drone_type: {
+      type: DataTypes.INTEGER,
+      allowNull: true
+    },
+    rssi: {
+      type: DataTypes.FLOAT,
+      allowNull: true
+    },
+    frequency: {
+      type: DataTypes.FLOAT,
+      allowNull: true
+    }
+  }, {
+    tableName: 'drone_detections',
+    timestamps: false,
+    indexes: [
+      {
+        fields: ['tenant_id', 'timestamp']
+      },
+      {
+        fields: ['timestamp']
+      }
+    ]
+  });
+
+  // Heartbeat model
+  models.Heartbeat = sequelize.define('Heartbeat', {
+    id: {
+      type: DataTypes.INTEGER,
+      primaryKey: true,
+      autoIncrement: true
+    },
+    tenant_id: {
+      type: DataTypes.INTEGER,
+      allowNull: false
+    },
+    device_id: {
+      type: DataTypes.STRING(50),
+      allowNull: false
+    },
+    timestamp: {
+      type: DataTypes.DATE,
+      allowNull: false
+    },
+    status: {
+      type: DataTypes.STRING(20),
+      defaultValue: 'online'
+    }
+  }, {
+    tableName: 'heartbeats',
+    timestamps: false,
+    indexes: [
+      {
+        fields: ['tenant_id', 'timestamp']
+      },
+      {
+        fields: ['timestamp']
+      }
+    ]
+  });
+
+  // SecurityLog model (optional, might not exist in all installations)
+  models.SecurityLog = sequelize.define('SecurityLog', {
+    id: {
+      type: DataTypes.INTEGER,
+      primaryKey: true,
+      autoIncrement: true
+    },
+    tenant_id: {
+      type: DataTypes.INTEGER,
+      allowNull: true
+    },
+    timestamp: {
+      type: DataTypes.DATE,
+      allowNull: false
+    },
+    level: {
+      type: DataTypes.STRING(20),
+      allowNull: false
+    },
+    message: {
+      type: DataTypes.TEXT,
+      allowNull: false
+    },
+    metadata: {
+      type: DataTypes.JSONB,
+      defaultValue: {}
+    }
+  }, {
+    tableName: 'security_logs',
+    timestamps: false,
+    indexes: [
+      {
+        fields: ['tenant_id', 'timestamp']
+      },
+      {
+        fields: ['timestamp']
+      }
+    ]
+  });
+}
+
+/**
+ * Get models
+ */
+async function getModels() {
+  if (!sequelize) {
+    await initializeDatabase();
+  }
+  return models;
+}
+
+/**
+ * Close database connection
+ */
+async function closeDatabase() {
+  if (sequelize) {
+    await sequelize.close();
+  }
+}
+
+module.exports = {
+  initializeDatabase,
+  getModels,
+  closeDatabase,
+  sequelize: () => sequelize
+};
\ No newline at end of file
diff --git a/data-retention-service/healthcheck.js b/data-retention-service/healthcheck.js
new file mode 100644
index 0000000..6a5f593
--- /dev/null
+++ b/data-retention-service/healthcheck.js
@@ -0,0 +1,21 @@
+/**
+ * Health check for Data Retention Service
+ */
+
+const { getModels } = require('./database');
+
+async function healthCheck() {
+  try {
+    // Check database connection
+    const { Tenant } = await getModels();
+    await Tenant.findOne({ limit: 1 });
+    
+    console.log('Health check passed');
+    process.exit(0);
+  } catch (error) {
+    console.error('Health check failed:', error);
+    process.exit(1);
+  }
+}
+
+healthCheck();
\ No newline at end of file
diff --git a/data-retention-service/index.js b/data-retention-service/index.js
new file mode 100644
index 0000000..013b1a2
--- /dev/null
+++ b/data-retention-service/index.js
@@ -0,0 +1,267 @@
+/**
+ * Data Retention Service
+ * Standalone microservice for automated data cleanup
+ */
+
+const cron = require('node-cron');
+const { Op } = require('sequelize');
+require('dotenv').config();
+
+// Initialize database connection
+const { initializeDatabase, getModels } = require('./database');
+
+class DataRetentionService {
+  constructor() {
+    this.isRunning = false;
+    this.lastCleanup = null;
+    this.cleanupStats = {
+      totalRuns: 0,
+      totalDetectionsDeleted: 0,
+      totalHeartbeatsDeleted: 0,
+      totalLogsDeleted: 0,
+      lastRunDuration: 0,
+      errors: []
+    };
+  }
+
+  /**
+   * Start the data retention cleanup service
+   */
+  async start() {
+    console.log('🗂️  Starting Data Retention Service...');
+    console.log(`📅 Environment: ${process.env.NODE_ENV || 'development'}`);
+    console.log(`💾 Database: ${process.env.DB_HOST}:${process.env.DB_PORT}/${process.env.DB_NAME}`);
+    
+    try {
+      // Initialize database connection
+      await initializeDatabase();
+      console.log('✅ Database connection established');
+      
+      // Schedule daily cleanup at 2:00 AM UTC
+      cron.schedule('0 2 * * *', async () => {
+        await this.performCleanup();
+      }, {
+        scheduled: true,
+        timezone: "UTC"
+      });
+
+      console.log('⏰ Scheduled cleanup: Daily at 2:00 AM UTC');
+
+      // Run immediate cleanup in development or if IMMEDIATE_CLEANUP is set
+      if (process.env.NODE_ENV === 'development' || process.env.IMMEDIATE_CLEANUP === 'true') {
+        console.log('🧹 Running immediate cleanup...');
+        setTimeout(() => this.performCleanup(), 5000);
+      }
+
+      // Health check endpoint simulation
+      setInterval(() => {
+        this.logHealthStatus();
+      }, 60000); // Every minute
+
+      console.log('✅ Data Retention Service started successfully');
+      
+    } catch (error) {
+      console.error('❌ Failed to start Data Retention Service:', error);
+      process.exit(1);
+    }
+  }
+
+  /**
+   * Perform cleanup for all tenants
+   */
+  async performCleanup() {
+    if (this.isRunning) {
+      console.log('⏳ Data retention cleanup already running, skipping...');
+      return;
+    }
+
+    this.isRunning = true;
+    const startTime = Date.now();
+    
+    try {
+      console.log('🧹 Starting data retention cleanup...');
+      console.log(`⏰ Cleanup started at: ${new Date().toISOString()}`);
+      
+      const { Tenant, DroneDetection, Heartbeat, SecurityLog } = await getModels();
+      
+      // Get all active tenants with their retention policies
+      const tenants = await Tenant.findAll({
+        attributes: ['id', 'slug', 'features'],
+        where: {
+          is_active: true
+        }
+      });
+
+      console.log(`🏢 Found ${tenants.length} active tenants to process`);
+
+      let totalDetectionsDeleted = 0;
+      let totalHeartbeatsDeleted = 0;
+      let totalLogsDeleted = 0;
+      let errors = [];
+
+      for (const tenant of tenants) {
+        try {
+          const result = await this.cleanupTenant(tenant);
+          totalDetectionsDeleted += result.detections;
+          totalHeartbeatsDeleted += result.heartbeats;
+          totalLogsDeleted += result.logs;
+        } catch (error) {
+          console.error(`❌ Error cleaning tenant ${tenant.slug}:`, error);
+          errors.push({
+            tenantSlug: tenant.slug,
+            error: error.message,
+            timestamp: new Date().toISOString()
+          });
+        }
+      }
+
+      const duration = Date.now() - startTime;
+      this.lastCleanup = new Date();
+      this.cleanupStats.totalRuns++;
+      this.cleanupStats.totalDetectionsDeleted += totalDetectionsDeleted;
+      this.cleanupStats.totalHeartbeatsDeleted += totalHeartbeatsDeleted;
+      this.cleanupStats.totalLogsDeleted += totalLogsDeleted;
+      this.cleanupStats.lastRunDuration = duration;
+      this.cleanupStats.errors = errors;
+
+      console.log('✅ Data retention cleanup completed');
+      console.log(`⏱️  Duration: ${duration}ms`);
+      console.log(`📊 Deleted: ${totalDetectionsDeleted} detections, ${totalHeartbeatsDeleted} heartbeats, ${totalLogsDeleted} logs`);
+      
+      if (errors.length > 0) {
+        console.log(`⚠️  Errors encountered: ${errors.length}`);
+        errors.forEach(err => console.log(`   - ${err.tenantSlug}: ${err.error}`));
+      }
+
+    } catch (error) {
+      console.error('❌ Data retention cleanup failed:', error);
+      this.cleanupStats.errors.push({
+        error: error.message,
+        timestamp: new Date().toISOString()
+      });
+    } finally {
+      this.isRunning = false;
+    }
+  }
+
+  /**
+   * Clean up data for a specific tenant
+   */
+  async cleanupTenant(tenant) {
+    const retentionDays = tenant.features?.data_retention_days;
+    
+    // Skip if unlimited retention (-1)
+    if (retentionDays === -1) {
+      console.log(`⏭️  Skipping tenant ${tenant.slug} - unlimited retention`);
+      return { detections: 0, heartbeats: 0, logs: 0 };
+    }
+
+    // Default to 90 days if not specified
+    const effectiveRetentionDays = retentionDays || 90;
+    const cutoffDate = new Date();
+    cutoffDate.setDate(cutoffDate.getDate() - effectiveRetentionDays);
+
+    console.log(`🧹 Cleaning tenant ${tenant.slug} - removing data older than ${effectiveRetentionDays} days (before ${cutoffDate.toISOString()})`);
+
+    const { DroneDetection, Heartbeat, SecurityLog } = await getModels();
+
+    // Clean up drone detections
+    const deletedDetections = await DroneDetection.destroy({
+      where: {
+        tenant_id: tenant.id,
+        timestamp: {
+          [Op.lt]: cutoffDate
+        }
+      }
+    });
+
+    // Clean up heartbeats
+    const deletedHeartbeats = await Heartbeat.destroy({
+      where: {
+        tenant_id: tenant.id,
+        timestamp: {
+          [Op.lt]: cutoffDate
+        }
+      }
+    });
+
+    // Clean up security logs (if they have tenant_id)
+    let deletedLogs = 0;
+    try {
+      deletedLogs = await SecurityLog.destroy({
+        where: {
+          tenant_id: tenant.id,
+          timestamp: {
+            [Op.lt]: cutoffDate
+          }
+        }
+      });
+    } catch (error) {
+      // SecurityLog might not have tenant_id field
+      console.log(`⚠️  Skipping security logs for tenant ${tenant.slug}: ${error.message}`);
+    }
+
+    console.log(`✅ Tenant ${tenant.slug}: Deleted ${deletedDetections} detections, ${deletedHeartbeats} heartbeats, ${deletedLogs} logs`);
+
+    return {
+      detections: deletedDetections,
+      heartbeats: deletedHeartbeats,
+      logs: deletedLogs
+    };
+  }
+
+  /**
+   * Log health status
+   */
+  logHealthStatus() {
+    const memUsage = process.memoryUsage();
+    const uptime = process.uptime();
+    
+    console.log(`💚 Health Check - Uptime: ${Math.floor(uptime)}s, Memory: ${Math.round(memUsage.heapUsed / 1024 / 1024)}MB, Last Cleanup: ${this.lastCleanup ? this.lastCleanup.toISOString() : 'Never'}`);
+  }
+
+  /**
+   * Get service statistics
+   */
+  getStats() {
+    return {
+      ...this.cleanupStats,
+      isRunning: this.isRunning,
+      lastCleanup: this.lastCleanup,
+      uptime: process.uptime(),
+      memoryUsage: process.memoryUsage(),
+      nextScheduledRun: '2:00 AM UTC daily'
+    };
+  }
+
+  /**
+   * Graceful shutdown
+   */
+  async shutdown() {
+    console.log('🔄 Graceful shutdown initiated...');
+    
+    // Wait for current cleanup to finish
+    while (this.isRunning) {
+      console.log('⏳ Waiting for cleanup to finish...');
+      await new Promise(resolve => setTimeout(resolve, 1000));
+    }
+    
+    console.log('✅ Data Retention Service stopped');
+    process.exit(0);
+  }
+}
+
+// Initialize and start the service
+const service = new DataRetentionService();
+
+// Handle graceful shutdown
+process.on('SIGTERM', () => service.shutdown());
+process.on('SIGINT', () => service.shutdown());
+
+// Start the service
+service.start().catch(error => {
+  console.error('Failed to start service:', error);
+  process.exit(1);
+});
+
+module.exports = DataRetentionService;
\ No newline at end of file
diff --git a/data-retention-service/package.json b/data-retention-service/package.json
new file mode 100644
index 0000000..52f0759
--- /dev/null
+++ b/data-retention-service/package.json
@@ -0,0 +1,24 @@
+{
+  "name": "data-retention-service",
+  "version": "1.0.0",
+  "description": "Automated data retention cleanup service for drone detection system",
+  "main": "index.js",
+  "scripts": {
+    "start": "node index.js",
+    "dev": "nodemon index.js",
+    "test": "jest"
+  },
+  "dependencies": {
+    "pg": "^8.11.3",
+    "sequelize": "^6.32.1",
+    "node-cron": "^3.0.2",
+    "dotenv": "^16.3.1"
+  },
+  "devDependencies": {
+    "nodemon": "^3.0.1",
+    "jest": "^29.6.1"
+  },
+  "engines": {
+    "node": ">=18.0.0"
+  }
+}
\ No newline at end of file
diff --git a/docker-compose.yml b/docker-compose.yml
index 616c9c8..1403a33 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -173,6 +173,39 @@ services:
       - simulation
     command: python drone_simulator.py --devices 5 --duration 3600
 
+  # Data Retention Service (Microservice)
+  data-retention:
+    build:
+      context: ./data-retention-service
+      dockerfile: Dockerfile
+    container_name: drone-detection-data-retention
+    restart: unless-stopped
+    environment:
+      DB_HOST: postgres
+      DB_PORT: 5432
+      DB_NAME: ${DB_NAME:-drone_detection}
+      DB_USER: ${DB_USER:-postgres}
+      DB_PASSWORD: ${DB_PASSWORD:-your_secure_password}
+      NODE_ENV: ${NODE_ENV:-production}
+      IMMEDIATE_CLEANUP: ${IMMEDIATE_CLEANUP:-false}
+    networks:
+      - drone-network
+    depends_on:
+      postgres:
+        condition: service_healthy
+    healthcheck:
+      test: ["CMD", "node", "healthcheck.js"]
+      interval: 30s
+      timeout: 10s
+      retries: 3
+    # Resource limits for lightweight container
+    deploy:
+      resources:
+        limits:
+          memory: 128M
+        reservations:
+          memory: 64M
+
   # Health Probe Simulator (Continuous Device Heartbeats)
   healthprobe:
     build:
diff --git a/server/index.js b/server/index.js
index 51f72b5..53f2287 100644
--- a/server/index.js
+++ b/server/index.js
@@ -236,7 +236,7 @@ async function startServer() {
       deviceHealthService.start();
       console.log('🏥 Device health monitoring: ✅ Started');
       
-      // Graceful shutdown for device health service
+      // Graceful shutdown for services
       process.on('SIGTERM', () => {
         console.log('SIGTERM received, shutting down gracefully');
         deviceHealthService.stop();
diff --git a/server/middleware/tenant-limits.js b/server/middleware/tenant-limits.js
index 462d4d4..99224ce 100644
--- a/server/middleware/tenant-limits.js
+++ b/server/middleware/tenant-limits.js
@@ -3,10 +3,10 @@
  * Enforces tenant subscription limits for users, devices, API rate limits, etc.
  */
 
-const MultiTenantAuth = require('./multi-tenant-auth');
 const { securityLogger } = require('./logger');
 
 // Initialize multi-tenant auth
+const MultiTenantAuth = require('./multi-tenant-auth');
 const multiAuth = new MultiTenantAuth();
 
 /**
diff --git a/server/routes/tenant.js b/server/routes/tenant.js
index 0350899..6d50707 100644
--- a/server/routes/tenant.js
+++ b/server/routes/tenant.js
@@ -616,6 +616,135 @@ router.put('/security', authenticateToken, requirePermissions(['security.edit'])
   }
 });
 
+/**
+ * GET /tenant/limits
+ * Get current tenant limits and usage status
+ */
+router.get('/limits', authenticateToken, async (req, res) => {
+  try {
+    // Determine tenant from request
+    const tenantId = await multiAuth.determineTenant(req);
+    if (!tenantId) {
+      return res.status(400).json({
+        success: false,
+        message: 'Unable to determine tenant'
+      });
+    }
+
+    const tenant = await Tenant.findOne({ where: { slug: tenantId } });
+    if (!tenant) {
+      return res.status(404).json({
+        success: false,
+        message: 'Tenant not found'
+      });
+    }
+
+    const { getTenantLimitsStatus } = require('../middleware/tenant-limits');
+    const limitsStatus = await getTenantLimitsStatus(tenant.id);
+
+    res.json({
+      success: true,
+      data: limitsStatus
+    });
+
+  } catch (error) {
+    console.error('Error fetching tenant limits:', error);
+    res.status(500).json({
+      success: false,
+      message: 'Failed to fetch tenant limits'
+    });
+  }
+});
+
+/**
+ * GET /tenant/data-retention/preview
+ * Preview what data would be deleted by retention cleanup
+ * Note: Actual cleanup is handled by separate data-retention-service container
+ */
+router.get('/data-retention/preview', authenticateToken, requirePermissions(['settings.view']), async (req, res) => {
+  try {
+    // Determine tenant from request
+    const tenantId = await multiAuth.determineTenant(req);
+    if (!tenantId) {
+      return res.status(400).json({
+        success: false,
+        message: 'Unable to determine tenant'
+      });
+    }
+
+    const tenant = await Tenant.findOne({ where: { slug: tenantId } });
+    if (!tenant) {
+      return res.status(404).json({
+        success: false,
+        message: 'Tenant not found'
+      });
+    }
+
+    // Calculate what would be deleted (preview only)
+    const retentionDays = tenant.features?.data_retention_days || 90;
+    
+    if (retentionDays === -1) {
+      return res.json({
+        success: true,
+        data: {
+          tenantSlug: tenant.slug,
+          retentionDays: 'unlimited',
+          cutoffDate: null,
+          toDelete: {
+            detections: 0,
+            heartbeats: 0,
+            logs: 0
+          },
+          note: 'This tenant has unlimited data retention'
+        }
+      });
+    }
+
+    const cutoffDate = new Date();
+    cutoffDate.setDate(cutoffDate.getDate() - retentionDays);
+
+    const { DroneDetection, Heartbeat } = require('../models');
+    const { Op } = require('sequelize');
+
+    const [detectionsCount, heartbeatsCount] = await Promise.all([
+      DroneDetection.count({
+        where: {
+          tenant_id: tenant.id,
+          timestamp: { [Op.lt]: cutoffDate }
+        }
+      }),
+      Heartbeat.count({
+        where: {
+          tenant_id: tenant.id,
+          timestamp: { [Op.lt]: cutoffDate }
+        }
+      })
+    ]);
+
+    res.json({
+      success: true,
+      data: {
+        tenantSlug: tenant.slug,
+        retentionDays,
+        cutoffDate: cutoffDate.toISOString(),
+        toDelete: {
+          detections: detectionsCount,
+          heartbeats: heartbeatsCount,
+          logs: 0 // Security logs are cleaned up by the data retention service
+        },
+        note: 'Actual cleanup is performed daily at 2:00 AM UTC by the data-retention-service container'
+      }
+    });
+
+  } catch (error) {
+    console.error('Error previewing data retention cleanup:', error);
+    res.status(500).json({
+      success: false,
+      message: 'Failed to preview data retention cleanup'
+    });
+  }
+});
+
 /**
  * GET /tenant/users
  * Get users in current tenant (user admin or higher)
diff --git a/server/services/dataRetention.js b/server/services/dataRetention.js
new file mode 100644
index 0000000..4efb50b
--- /dev/null
+++ b/server/services/dataRetention.js
@@ -0,0 +1,292 @@
+/**
+ * Data Retention Service
+ * Automatically cleans up old data based on tenant retention policies
+ */
+
+const cron = require('node-cron');
+const { Op } = require('sequelize');
+const { securityLogger } = require('../middleware/logger');
+
+class DataRetentionService {
+  constructor() {
+    this.isRunning = false;
+    this.lastCleanup = null;
+    this.cleanupStats = {
+      totalRuns: 0,
+      totalDetectionsDeleted: 0,
+      totalHeartbeatsDeleted: 0,
+      totalLogsDeleted: 0,
+      lastRunDuration: 0
+    };
+  }
+
+  /**
+   * Start the data retention cleanup service
+   * Runs daily at 2 AM
+   */
+  start() {
+    console.log('🗂️  Starting Data Retention Service...');
+    
+    // Run daily at 2:00 AM
+    cron.schedule('0 2 * * *', async () => {
+      await this.performCleanup();
+    }, {
+      scheduled: true,
+      timezone: "UTC"
+    });
+
+    // Also run immediately if NODE_ENV is development
+    if (process.env.NODE_ENV === 'development') {
+      console.log('🧹 Development mode: Running initial data retention cleanup...');
+      setTimeout(() => this.performCleanup(), 5000); // Wait 5 seconds for app to fully start
+    }
+
+    console.log('✅ Data Retention Service started - will run daily at 2:00 AM UTC');
+  }
+
+  /**
+   * Perform cleanup for all tenants
+   */
+  async performCleanup() {
+    if (this.isRunning) {
+      console.log('⏳ Data retention cleanup already running, skipping...');
+      return;
+    }
+
+    this.isRunning = true;
+    const startTime = Date.now();
+    
+    try {
+      console.log('🧹 Starting data retention cleanup...');
+      
+      const { Tenant, DroneDetection, Heartbeat, SecurityLog } = require('../models');
+      
+      // Get all tenants with their retention policies
+      const tenants = await Tenant.findAll({
+        attributes: ['id', 'slug', 'features'],
+        where: {
+          is_active: true
+        }
+      });
+
+      let totalDetectionsDeleted = 0;
+      let totalHeartbeatsDeleted = 0;
+      let totalLogsDeleted = 0;
+
+      for (const tenant of tenants) {
+        const retentionDays = tenant.features?.data_retention_days;
+        
+        // Skip if unlimited retention (-1)
+        if (retentionDays === -1) {
+          console.log(`⏭️  Skipping tenant ${tenant.slug} - unlimited retention`);
+          continue;
+        }
+
+        // Default to 90 days if not specified
+        const effectiveRetentionDays = retentionDays || 90;
+        const cutoffDate = new Date();
+        cutoffDate.setDate(cutoffDate.getDate() - effectiveRetentionDays);
+
+        console.log(`🧹 Cleaning tenant ${tenant.slug} - removing data older than ${effectiveRetentionDays} days (before ${cutoffDate.toISOString()})`);
+
+        try {
+          // Clean up drone detections
+          const deletedDetections = await DroneDetection.destroy({
+            where: {
+              tenant_id: tenant.id,
+              timestamp: {
+                [Op.lt]: cutoffDate
+              }
+            }
+          });
+
+          // Clean up heartbeats
+          const deletedHeartbeats = await Heartbeat.destroy({
+            where: {
+              tenant_id: tenant.id,
+              timestamp: {
+                [Op.lt]: cutoffDate
+              }
+            }
+          });
+
+          // Clean up security logs (if they have tenant_id)
+          let deletedLogs = 0;
+          try {
+            deletedLogs = await SecurityLog.destroy({
+              where: {
+                tenant_id: tenant.id,
+                timestamp: {
+                  [Op.lt]: cutoffDate
+                }
+              }
+            });
+          } catch (error) {
+            // SecurityLog might not have tenant_id field, skip if error
+            console.log(`⚠️  Skipping security logs cleanup for tenant ${tenant.slug}: ${error.message}`);
+          }
+
+          totalDetectionsDeleted += deletedDetections;
+          totalHeartbeatsDeleted += deletedHeartbeats;
+          totalLogsDeleted += deletedLogs;
+
+          console.log(`✅ Tenant ${tenant.slug}: Deleted ${deletedDetections} detections, ${deletedHeartbeats} heartbeats, ${deletedLogs} logs`);
+
+          // Log significant cleanup events
+          if (deletedDetections > 100 || deletedHeartbeats > 100) {
+            securityLogger.logSecurityEvent('info', 'Data retention cleanup performed', {
+              action: 'data_retention_cleanup',
+              tenantId: tenant.id,
+              tenantSlug: tenant.slug,
+              retentionDays: effectiveRetentionDays,
+              cutoffDate: cutoffDate.toISOString(),
+              deletedDetections,
+              deletedHeartbeats,
+              deletedLogs
+            });
+          }
+
+        } catch (error) {
+          console.error(`❌ Error cleaning tenant ${tenant.slug}:`, error);
+          
+          securityLogger.logSecurityEvent('error', 'Data retention cleanup failed', {
+            action: 'data_retention_cleanup_error',
+            tenantId: tenant.id,
+            tenantSlug: tenant.slug,
+            error: error.message,
+            stack: error.stack
+          });
+        }
+      }
+
+      const duration = Date.now() - startTime;
+      this.lastCleanup = new Date();
+      this.cleanupStats.totalRuns++;
+      this.cleanupStats.totalDetectionsDeleted += totalDetectionsDeleted;
+      this.cleanupStats.totalHeartbeatsDeleted += totalHeartbeatsDeleted;
+      this.cleanupStats.totalLogsDeleted += totalLogsDeleted;
+      this.cleanupStats.lastRunDuration = duration;
+
+      console.log(`✅ Data retention cleanup completed in ${duration}ms`);
+      console.log(`📊 Total deleted: ${totalDetectionsDeleted} detections, ${totalHeartbeatsDeleted} heartbeats, ${totalLogsDeleted} logs`);
+
+      // Log cleanup summary
+      securityLogger.logSecurityEvent('info', 'Data retention cleanup completed', {
+        action: 'data_retention_cleanup_summary',
+        duration,
+        tenantsProcessed: tenants.length,
+        totalDetectionsDeleted,
+        totalHeartbeatsDeleted,
+        totalLogsDeleted,
+        timestamp: new Date().toISOString()
+      });
+
+    } catch (error) {
+      console.error('❌ Data retention cleanup failed:', error);
+      
+      securityLogger.logSecurityEvent('error', 'Data retention cleanup service failed', {
+        action: 'data_retention_service_error',
+        error: error.message,
+        stack: error.stack,
+        timestamp: new Date().toISOString()
+      });
+    } finally {
+      this.isRunning = false;
+    }
+  }
+
+  /**
+   * Get cleanup statistics
+   */
+  getStats() {
+    return {
+      ...this.cleanupStats,
+      isRunning: this.isRunning,
+      lastCleanup: this.lastCleanup,
+      nextScheduledRun: '2:00 AM UTC daily'
+    };
+  }
+
+  /**
+   * Manually trigger cleanup (for testing/admin use)
+   */
+  async triggerManualCleanup() {
+    console.log('🔧 Manual data retention cleanup triggered');
+    await this.performCleanup();
+  }
+
+  /**
+   * Preview what would be deleted for a specific tenant
+   */
+  async previewCleanup(tenantId) {
+    try {
+      const { Tenant, DroneDetection, Heartbeat, SecurityLog } = require('../models');
+      
+      const tenant = await Tenant.findByPk(tenantId);
+      if (!tenant) {
+        throw new Error('Tenant not found');
+      }
+
+      const retentionDays = tenant.features?.data_retention_days || 90;
+      
+      if (retentionDays === -1) {
+        return {
+          tenantSlug: tenant.slug,
+          retentionDays: 'unlimited',
+          toDelete: {
+            detections: 0,
+            heartbeats: 0,
+            logs: 0
+          }
+        };
+      }
+
+      const cutoffDate = new Date();
+      cutoffDate.setDate(cutoffDate.getDate() - retentionDays);
+
+      const [detectionsCount, heartbeatsCount] = await Promise.all([
+        DroneDetection.count({
+          where: {
+            tenant_id: tenant.id,
+            timestamp: { [Op.lt]: cutoffDate }
+          }
+        }),
+        Heartbeat.count({
+          where: {
+            tenant_id: tenant.id,
+            timestamp: { [Op.lt]: cutoffDate }
+          }
+        })
+      ]);
+
+      let logsCount = 0;
+      try {
+        logsCount = await SecurityLog.count({
+          where: {
+            tenant_id: tenant.id,
+            timestamp: { [Op.lt]: cutoffDate }
+          }
+        });
+      } catch (error) {
+        // SecurityLog might not have tenant_id
+      }
+
+      return {
+        tenantSlug: tenant.slug,
+        retentionDays,
+        cutoffDate: cutoffDate.toISOString(),
+        toDelete: {
+          detections: detectionsCount,
+          heartbeats: heartbeatsCount,
+          logs: logsCount
+        }
+      };
+
+    } catch (error) {
+      console.error('Error previewing cleanup:', error);
+      throw error;
+    }
+  }
+}
+
+module.exports = DataRetentionService;
\ No newline at end of file