EventBridge: Stop Polling Like It's 1999 📡⚡

Real talk: The first time I needed to sync data between services, I did what every developer does - I wrote a cron job that checked for changes every 5 seconds. "It works!" I thought. Then I checked CloudWatch metrics: 17 million Lambda invocations per month checking if ANYTHING changed. Only 2% found actual changes. 💸

My boss asked, "Why is our Lambda bill $287/month for a feature that processes 50 events per day?" Narrator: Because I was polling like a caveman. 😅

Welcome to EventBridge - the AWS service that makes your architecture "react" instead of "check constantly!"

What Even Is EventBridge? (Beyond "AWS Event Bus") 🤔

EventBridge = AWS's serverless event bus - Think of it as a smart notification system where services can broadcast "hey, something happened!" and other services listen and react.

Think of it like: A radio station for your AWS services. Publishers broadcast events, subscribers tune in to what they care about!

Without EventBridge (Polling Hell):

Every 5 seconds:
  Lambda → "Hey RDS, anything new?" → RDS checks → "Nope"
  Lambda → "Hey RDS, anything new?" → RDS checks → "Nope"
  Lambda → "Hey RDS, anything new?" → RDS checks → "Nope"
  Lambda → "Hey RDS, anything new?" → RDS checks → "YES!"

Cost: 17M Lambda invocations/month = $287
Latency: Up to 5 second delay
Database load: Constant hammering

With EventBridge (Event-Driven Heaven):

When something happens:
  Service → EventBridge → "New order created!"
  EventBridge → Lambda → Processes immediately

Cost: 50 events/month = $0.00 (first 1M events are FREE!)
Latency: Sub-second reaction
Database load: Zero polling queries

Translation: EventBridge = Stop asking "are we there yet?" and get notified when you arrive! 🎯

The $287 Polling Bill: My EventBridge Awakening 💀

When architecting our e-commerce backend, we needed to process new orders. Here's what I naively built:

The polling nightmare:

// BAD: Polling for new orders every 5 seconds
exports.handler = async (event) => {
  console.log('Checking for new orders...');

  // Query database for unprocessed orders
  const newOrders = await db.orders.find({
    status: 'pending',
    processedAt: null,
    createdAt: { $gte: Date.now() - 5000 } // Last 5 seconds
  });

  console.log(`Found ${newOrders.length} new orders`);

  if (newOrders.length === 0) {
    // 98% of invocations end here! 💸
    return { statusCode: 200, message: 'No new orders' };
  }

  // Process orders
  for (const order of newOrders) {
    await processOrder(order);
    await db.orders.update(order.id, { processedAt: Date.now() });
  }

  return { statusCode: 200, processed: newOrders.length };
};

Scheduled via EventBridge Rule (ironically):

# Trigger Lambda every 5 seconds
aws events put-rule \
  --name check-orders-every-5-seconds \
  --schedule-expression "rate(5 seconds)"

aws events put-targets \
  --rule check-orders-every-5-seconds \
  --targets "Id=1,Arn=arn:aws:lambda:us-east-1:123:function:process-orders"

What happened:

Daily stats:
- Lambda invocations: 17,280 (86,400 seconds / 5)
- Orders found: ~350 orders/day
- Wasted invocations: 16,930 (98% found NOTHING!)
- Database queries: 17,280/day (constant load)

Monthly cost:
- Lambda: 17,280 × 30 = 518,400 invocations
- At $0.20 per 1M requests = $0.10 (cheap!)
- But duration: 200ms avg × 518,400 = 103,680 seconds
- GB-seconds: 103,680 × 0.128GB = 13,271 GB-seconds
- At $0.0000166667 per GB-second = $221
- Database I/O: 518,400 queries × $0.20/1M = $0.10
- **Total: $221.20/month to process 10,500 orders!** 😱

The real costs:

❌ Wasting money on empty polls
❌ Database constantly under load (connection pool exhaustion!)
❌ Up to 5-second delay before processing
❌ Scaling issues (can't poll faster without crushing DB)

After switching to EventBridge:

// GOOD: Event-driven order processing
exports.handler = async (event) => {
  // EventBridge sends order details directly!
  const order = JSON.parse(event.detail);

  console.log(`Processing order ${order.id}`);

  // Process immediately (no database query needed!)
  await processOrder(order);

  // Update status
  await db.orders.update(order.id, { processedAt: Date.now() });

  return { statusCode: 200, processed: order.id };
};

EventBridge Rule (pattern matching):

{
  "source": ["myapp.orders"],
  "detail-type": ["Order Created"],
  "detail": {
    "status": ["pending"]
  }
}

Results:

Lambda invocations: 10,500/month (98% reduction!)
Database queries: 10,500/month (98% reduction!)
Processing latency: 5 seconds → 100ms (98% faster!)
Cost: $221/month → $21/month (90% cheaper!)
Saved: $200/month! 💰

In production, I've deployed event-driven architectures that process millions of events per month for less than what polling cost us for thousands! 🎉

EventBridge Mistake #1: Not Understanding Event Patterns 🚨

The problem:

// BAD: Catch-all rule (triggers on EVERYTHING!)
const rule = {
  EventPattern: JSON.stringify({
    source: ["myapp"]
  })
};

// This triggers on:
// - User logins (don't need to process!)
// - Page views (don't care!)
// - Debug events (way too noisy!)
// - Actual orders (what we want)
// Result: Lambda overwhelmed with irrelevant events! 😱

The fix - Specific event patterns:

{
  "source": ["myapp.orders"],
  "detail-type": ["Order Created"],
  "detail": {
    "status": ["pending"],
    "amount": [{ "numeric": [">=", 100] }]
  }
}

Translation: Only trigger for "Order Created" events from the orders service where status is "pending" AND amount is >= $100!

Real examples of pattern matching:

Example 1: Geographic filtering

{
  "source": ["myapp.users"],
  "detail-type": ["User Registered"],
  "detail": {
    "country": ["US", "CA", "MX"]
  }
}

Only triggers for users from North America! 🌎

Example 2: Numeric ranges

{
  "source": ["myapp.transactions"],
  "detail-type": ["Payment Processed"],
  "detail": {
    "amount": [{ "numeric": [">", 10000] }]
  }
}

Only high-value transactions! Perfect for fraud detection! 🔍

Example 3: Prefix matching

{
  "source": ["myapp.errors"],
  "detail-type": [{ "prefix": "Critical" }]
}

Matches: "Critical Error", "Critical Alert", "Critical Warning"! 🚨

Example 4: Anything-but filtering

{
  "source": ["myapp.orders"],
  "detail": {
    "status": [{ "anything-but": ["cancelled", "refunded"] }]
  }
}

Matches all statuses EXCEPT cancelled/refunded! ✅

A serverless pattern that saved us: Be SPECIFIC with event patterns! Catching everything is like subscribing to every subreddit - you'll drown in noise! 📡

EventBridge Mistake #2: Not Using Custom Event Buses 🚌

The problem - Everything on the default bus:

// BAD: All events on default bus (chaos!)
await eventBridge.putEvents({
  Entries: [
    { Source: 'myapp.orders', DetailType: 'Order Created', Detail: '{}' },
    { Source: 'myapp.users', DetailType: 'User Login', Detail: '{}' },
    { Source: 'myapp.payments', DetailType: 'Payment Failed', Detail: '{}' },
    { Source: 'third-party.webhooks', DetailType: 'Stripe Event', Detail: '{}' },
    { Source: 'internal.debug', DetailType: 'Debug Log', Detail: '{}' }
  ]
}).promise();

// Everything mixed together!
// - Production events
// - Development events
// - Third-party webhooks
// - Debug logs
// Result: Rules become VERY complex to filter! 😵

The fix - Separate event buses:

# Create custom event buses
aws events create-event-bus --name production-events
aws events create-event-bus --name third-party-webhooks
aws events create-event-bus --name development-events

Use them properly:

// Production application events
await eventBridge.putEvents({
  Entries: [{
    Source: 'myapp.orders',
    DetailType: 'Order Created',
    Detail: JSON.stringify(orderData),
    EventBusName: 'production-events' // Dedicated bus!
  }]
}).promise();

// Third-party webhooks
await eventBridge.putEvents({
  Entries: [{
    Source: 'stripe',
    DetailType: 'payment.succeeded',
    Detail: JSON.stringify(stripeEvent),
    EventBusName: 'third-party-webhooks' // Separate bus!
  }]
}).promise();

Benefits:

✅ Organize events by domain/purpose
✅ Different permissions per bus (security!)
✅ Easier to debug (filter by bus)
✅ Prevent cross-contamination
✅ Better cost tracking (separate billing!)

My production setup:

production-events:
  ├── Order events
  ├── User events
  └── Payment events

third-party-webhooks:
  ├── Stripe events
  ├── SendGrid events
  └── Twilio events

development-events:
  ├── Test events
  └── Debug events

When architecting on AWS, I learned: Custom event buses = organization! Don't throw everything into the default bus! 🎯

EventBridge Mistake #3: Not Using Dead Letter Queues (DLQ) ☠️

The disaster scenario:

// EventBridge rule triggers Lambda
exports.handler = async (event) => {
  const order = JSON.parse(event.detail);

  // Process order
  const result = await processPayment(order);

  if (!result.success) {
    throw new Error('Payment failed!'); // Lambda throws error
  }

  return { statusCode: 200 };
};

// Lambda fails → EventBridge retries (2 times)
// All retries fail → Event is LOST FOREVER! 💀
// No record, no alert, no way to recover!

What actually happened:

Event: Order #12345 ($500 purchase)
  → Lambda invocation #1: Payment API timeout (fail)
  → Lambda invocation #2: Payment API timeout (fail)
  → EventBridge gives up
  → Customer charged, order never processed
  → Support ticket: "Where's my order?!"
  → Me: "Uhh... EventBridge ate it?" 😰

The fix - Dead Letter Queue:

# Create SQS DLQ
aws sqs create-queue --queue-name eventbridge-dlq

# Create EventBridge rule with DLQ
aws events put-rule \
  --name process-orders \
  --event-pattern file://pattern.json

aws events put-targets \
  --rule process-orders \
  --targets '[{
    "Id": "1",
    "Arn": "arn:aws:lambda:us-east-1:123:function:process-orders",
    "DeadLetterConfig": {
      "Arn": "arn:aws:sqs:us-east-1:123:eventbridge-dlq"
    },
    "RetryPolicy": {
      "MaximumRetryAttempts": 3,
      "MaximumEventAge": 3600
    }
  }]'

Monitor DLQ and retry failed events:

// Poll DLQ for failed events
const messages = await sqs.receiveMessage({
  QueueUrl: 'https://sqs.us-east-1.amazonaws.com/123/eventbridge-dlq',
  MaxNumberOfMessages: 10
}).promise();

for (const message of messages.Messages) {
  const failedEvent = JSON.parse(message.Body);

  console.error('Failed event:', {
    orderId: failedEvent.detail.orderId,
    attempts: failedEvent.RetryAttempts,
    error: failedEvent.ErrorMessage
  });

  // Alert ops team
  await sns.publish({
    TopicArn: 'arn:aws:sns:us-east-1:123:critical-alerts',
    Subject: 'EventBridge event failed!',
    Message: `Order ${failedEvent.detail.orderId} failed processing after 3 retries!`
  }).promise();

  // Optionally: Manual retry after fixing issue
  // await eventBridge.putEvents({ Entries: [failedEvent] }).promise();
}

Set up CloudWatch alarm:

# Alert when DLQ has messages
aws cloudwatch put-metric-alarm \
  --alarm-name eventbridge-dlq-has-messages \
  --metric-name ApproximateNumberOfMessagesVisible \
  --namespace AWS/SQS \
  --statistic Average \
  --period 60 \
  --threshold 1 \
  --comparison-operator GreaterThanThreshold \
  --dimensions Name=QueueName,Value=eventbridge-dlq \
  --evaluation-periods 1 \
  --alarm-actions arn:aws:sns:us-east-1:123:critical-alerts

A production pattern that saved us: DLQ = event insurance! We've recovered thousands of failed events that would've been lost forever! 🛟

EventBridge Mistake #4: Publishing Giant Events 📏

The problem:

// BAD: Entire order object in event (400KB!)
await eventBridge.putEvents({
  Entries: [{
    Source: 'myapp.orders',
    DetailType: 'Order Created',
    Detail: JSON.stringify({
      orderId: '12345',
      customer: { /* full customer object */ },
      items: [ /* 100 products with full details */ ],
      shippingAddress: { /* ... */ },
      billingAddress: { /* ... */ },
      paymentMethod: { /* ... */ },
      orderHistory: [ /* last 50 orders */ ],
      recommendations: [ /* 20 products */ ]
      // Total: 400KB! EventBridge limit is 256KB! 💥
    })
  }]
}).promise();

// Error: Event size exceeds 256KB limit!

EventBridge limits:

Max event size: 256 KB
Max events per PutEvents call: 10
Max rate: 10,000 events/second per account

The fix - Event Claim Check pattern:

// GOOD: Store large data in S3, send reference in event
const AWS = require('aws-sdk');
const s3 = new AWS.S3();
const eventBridge = new AWS.EventBridge();

// 1. Store full order in S3
const s3Key = `orders/${orderId}/full-details.json`;
await s3.putObject({
  Bucket: 'order-details',
  Key: s3Key,
  Body: JSON.stringify(fullOrderData),
  ContentType: 'application/json'
}).promise();

// 2. Send lightweight event with S3 reference
await eventBridge.putEvents({
  Entries: [{
    Source: 'myapp.orders',
    DetailType: 'Order Created',
    Detail: JSON.stringify({
      orderId: '12345',
      customerId: 'user-789',
      total: 299.99,
      status: 'pending',
      s3Bucket: 'order-details',
      s3Key: s3Key, // Reference to full data!
      timestamp: Date.now()
    })
    // Total: 0.5KB (512× smaller!)
  }]
}).promise();

// 3. Consumer retrieves full data from S3 if needed
exports.handler = async (event) => {
  const { orderId, s3Bucket, s3Key } = JSON.parse(event.detail);

  // Only fetch full data if needed
  const fullData = await s3.getObject({
    Bucket: s3Bucket,
    Key: s3Key
  }).promise();

  const order = JSON.parse(fullData.Body.toString());

  await processOrder(order);
};

Benefits:

✅ Events stay under 256KB limit
✅ Faster event delivery (smaller payload)
✅ Consumers can skip fetching if not needed
✅ Audit trail (S3 has versioning!)
✅ Cheaper (S3 storage << EventBridge throughput)

Cost comparison:

Publishing 1M events/month with 400KB payload:

Option 1: Inline data (if it were possible)
- EventBridge: 1M events × $1.00/million = $1.00
- Data transfer: 400GB × $0.09/GB = $36.00
- Total: $37/month

Option 2: S3 Claim Check
- EventBridge: 1M events × $1.00/million = $1.00
- S3 PUT: 1M × $0.005/1000 = $5.00
- S3 GET: 1M × $0.0004/1000 = $0.40
- S3 storage: 400GB × $0.023/GB = $9.20
- Total: $15.60/month
- **Savings: $21.40/month (58% cheaper!)** 💰

EventBridge Mistake #5: Not Versioning Events 📋

The breaking change nightmare:

// Version 1: Original event
await eventBridge.putEvents({
  Entries: [{
    Source: 'myapp.orders',
    DetailType: 'Order Created',
    Detail: JSON.stringify({
      orderId: '12345',
      userId: 'user-789',
      total: 299.99
    })
  }]
}).promise();

// Consumer V1
exports.handler = async (event) => {
  const { userId, total } = JSON.parse(event.detail);
  // Works fine!
};

// Later: Changed event structure (BREAKING!)
await eventBridge.putEvents({
  Entries: [{
    Source: 'myapp.orders',
    DetailType: 'Order Created',
    Detail: JSON.stringify({
      orderId: '12345',
      customer: { id: 'user-789', email: '[email protected]' }, // Changed!
      amount: 299.99 // Renamed!
    })
  }]
}).promise();

// Consumer V1 (still running)
exports.handler = async (event) => {
  const { userId, total } = JSON.parse(event.detail);
  console.log(userId); // undefined! 💥
  console.log(total);  // undefined! 💥
  // EVERYTHING BREAKS!
};

The fix - Versioned events:

// Include version in DetailType
await eventBridge.putEvents({
  Entries: [{
    Source: 'myapp.orders',
    DetailType: 'Order Created v2', // Version in type!
    Detail: JSON.stringify({
      version: '2.0', // Also in payload
      orderId: '12345',
      customer: { id: 'user-789', email: '[email protected]' },
      amount: 299.99
    })
  }]
}).promise();

// Old consumer (still works!)
exports.oldHandler = async (event) => {
  if (event['detail-type'] === 'Order Created') {
    const { userId, total } = JSON.parse(event.detail);
    // Still works with old events!
  }
};

// New consumer (handles both!)
exports.newHandler = async (event) => {
  const detail = JSON.parse(event.detail);

  let userId, total;

  if (detail.version === '1.0') {
    // Handle old format
    userId = detail.userId;
    total = detail.total;
  } else if (detail.version === '2.0') {
    // Handle new format
    userId = detail.customer.id;
    total = detail.amount;
  }

  await processOrder(userId, total);
};

Event pattern for versioned events:

{
  "source": ["myapp.orders"],
  "detail-type": [
    "Order Created",
    "Order Created v2"
  ]
}

When architecting event-driven systems, I learned: Events are contracts! Version them like APIs! Breaking changes = breaking consumers! 🎯

EventBridge Mistake #6: Not Using EventBridge Pipes 🚰

The problem - Lambda glue code:

// BAD: Lambda just forwards events (waste of money!)
exports.handler = async (event) => {
  // SQS → Lambda → EventBridge (unnecessary hop!)
  const messages = event.Records;

  for (const message of messages) {
    await eventBridge.putEvents({
      Entries: [{
        Source: 'myapp.queue',
        DetailType: 'Message Received',
        Detail: message.body
      }]
    }).promise();
  }

  return { statusCode: 200 };
  // Cost: Lambda invocations + execution time
  // Why? Just to move data from A to B!
};

The fix - EventBridge Pipes (no Lambda!):

# Create pipe: SQS → EventBridge (direct!)
aws pipes create-pipe \
  --name sqs-to-eventbridge \
  --source arn:aws:sqs:us-east-1:123:orders-queue \
  --target arn:aws:events:us-east-1:123:event-bus/production-events \
  --role-arn arn:aws:iam::123:role/eventbridge-pipe-role \
  --source-parameters '{
    "SqsQueueParameters": {
      "BatchSize": 10
    }
  }' \
  --target-parameters '{
    "EventBridgeEventBusParameters": {
      "DetailType": "Queue Message",
      "Source": "myapp.queue"
    }
  }'

EventBridge Pipes supports:

Sources: SQS, Kinesis, DynamoDB Streams, Kafka
Targets: EventBridge, Lambda, Step Functions, API Gateway, SQS, SNS
Filtering: Built-in event filtering (no code!)
Enrichment: Call Lambda or API to transform data

Example with filtering and enrichment:

aws pipes create-pipe \
  --name filtered-enriched-pipe \
  --source arn:aws:sqs:us-east-1:123:raw-events \
  --target arn:aws:events:us-east-1:123:event-bus/production-events \
  --role-arn arn:aws:iam::123:role/pipe-role \
  --source-parameters '{
    "FilterCriteria": {
      "Filters": [{
        "Pattern": "{\"body\": {\"amount\": [{\"numeric\": [\">\", 100]}]}}"
      }]
    }
  }' \
  --enrichment arn:aws:lambda:us-east-1:123:function:enrich-event \
  --target-parameters '{
    "EventBridgeEventBusParameters": {
      "DetailType": "Enriched Event",
      "Source": "myapp.enriched"
    }
  }'

Cost comparison (1M events/month):

Lambda glue code:
- Lambda invocations: 1M × $0.20/million = $0.20
- Lambda duration: 1M × 100ms × $0.0000166667/GB-sec = $21.33
- Total: $21.53/month

EventBridge Pipe:
- Pipe processing: 1M × $0.40/million = $0.40/month
- **Savings: $21.13/month (98% cheaper!)** 💰

A serverless pattern that saved us: Use Pipes for simple integrations! Skip Lambda when you just need data movement! 🚰

Real-World EventBridge Patterns I Use in Production 🎯

Pattern 1: Fan-Out Processing

// One event triggers multiple independent processes
await eventBridge.putEvents({
  Entries: [{
    Source: 'myapp.orders',
    DetailType: 'Order Created',
    Detail: JSON.stringify({ orderId: '12345', total: 299.99 })
  }]
}).promise();

// Multiple Lambda functions react independently:
// 1. process-payment → Charge customer
// 2. send-confirmation-email → Email customer
// 3. update-inventory → Reduce stock
// 4. notify-fulfillment → Alert warehouse
// 5. trigger-analytics → Track conversion

// All in parallel! No orchestration needed! 🎉

Pattern 2: Saga Pattern (Distributed Transactions)

// Order Saga: coordinate multi-step process
const saga = new StateMachine({
  steps: [
    'Reserve Inventory',
    'Process Payment',
    'Create Shipment',
    'Send Confirmation'
  ]
});

// EventBridge + Step Functions
// Step 1: Reserve Inventory
await eventBridge.putEvents({
  Entries: [{
    Source: 'myapp.saga',
    DetailType: 'Saga Started',
    Detail: JSON.stringify({ sagaId, step: 'reserve-inventory' })
  }]
});

// If any step fails → Compensating events
if (paymentFailed) {
  await eventBridge.putEvents({
    Entries: [{
      Source: 'myapp.saga',
      DetailType: 'Saga Compensate',
      Detail: JSON.stringify({
        sagaId,
        action: 'release-inventory' // Undo!
      })
    }]
  });
}

Pattern 3: Event Replay (Debugging/Recovery)

// Archive events for replay
await eventBridge.createArchive({
  ArchiveName: 'production-orders-archive',
  EventSourceArn: 'arn:aws:events:us-east-1:123:event-bus/production-events',
  RetentionDays: 365
}).promise();

// Later: Replay failed events
await eventBridge.startReplay({
  ReplayName: 'recover-failed-orders',
  EventSourceArn: 'arn:aws:events:us-east-1:123:event-bus/production-events',
  EventStartTime: new Date('2024-02-01'),
  EventEndTime: new Date('2024-02-02'),
  Destination: {
    Arn: 'arn:aws:events:us-east-1:123:event-bus/replay-bus'
  }
}).promise();

// Replay events to test fixed Lambda!

Pattern 4: Cross-Account Events

// Account A: Publisher
await eventBridge.putEvents({
  Entries: [{
    Source: 'account-a.orders',
    DetailType: 'Order Created',
    Detail: JSON.stringify(orderData),
    EventBusName: 'arn:aws:events:us-east-1:999:event-bus/shared-events'
  }]
}).promise();

// Account B: Consumer (separate AWS account!)
// Receives events from Account A's bus
// Use case: Multi-tenant SaaS, partner integrations

The EventBridge Cost Optimization Playbook 💰

1. Use Event Filtering (Not Lambda Filtering)

// BAD: Lambda filters events (costs money!)
exports.handler = async (event) => {
  const order = JSON.parse(event.detail);

  if (order.amount < 100) {
    return; // Filtered out, but Lambda still invoked! 💸
  }

  await processOrder(order);
};

// GOOD: EventBridge filters (FREE!)
{
  "source": ["myapp.orders"],
  "detail-type": ["Order Created"],
  "detail": {
    "amount": [{ "numeric": [">=", 100] }]
  }
}
// Lambda ONLY invoked for orders >= $100!

2. Batch Events When Possible

// BAD: 1000 separate events
for (const item of items) {
  await eventBridge.putEvents({
    Entries: [{ Source: 'myapp', DetailType: 'Item', Detail: JSON.stringify(item) }]
  }).promise();
}
// Cost: 1000 API calls

// GOOD: Batch up to 10 events per call
const batches = chunk(items, 10);
for (const batch of batches) {
  await eventBridge.putEvents({
    Entries: batch.map(item => ({
      Source: 'myapp',
      DetailType: 'Item',
      Detail: JSON.stringify(item)
    }))
  }).promise();
}
// Cost: 100 API calls (10× cheaper!)

3. Use EventBridge Scheduler for Cron

# Instead of: Lambda with EventBridge cron rule
# Use: EventBridge Scheduler (newer, better!)

aws scheduler create-schedule \
  --name process-daily-reports \
  --schedule-expression "cron(0 9 * * ? *)" \
  --target '{
    "Arn": "arn:aws:lambda:us-east-1:123:function:daily-reports",
    "RoleArn": "arn:aws:iam::123:role/scheduler-role"
  }' \
  --flexible-time-window '{"Mode": "OFF"}'

Benefits:

More flexible scheduling
Better error handling
Built-in retries
One-time schedules supported

The Bottom Line 💡

EventBridge isn't just "another AWS service" - it's the paradigm shift from polling to reacting!

The essentials:

Stop polling (use events!)
Be specific with event patterns (filter early)
Use custom buses (organize events)
Add DLQs (never lose events)
Keep events small (use S3 for large data)
Version events (avoid breaking changes)
Use Pipes (skip Lambda glue code)

The truth about EventBridge:

It's not "just a message bus" - it's event-driven architecture made easy! When you stop asking "is there new data?" and start reacting to "data changed!" your architecture becomes faster, cheaper, and more scalable!

When architecting our e-commerce backend, I learned: Polling is the enemy of scalability. Events are the solution. EventBridge makes it dead simple. First 1M events per month are FREE. After that, $1 per million. Compare that to polling costs and the choice is obvious! 🎯

You don't need perfect event-driven architecture from day one - you need to START reacting instead of polling! 🚀

Your Action Plan 🎯

This week:

Identify polling loops in your codebase
Create your first custom event bus
Publish your first event
Set up a Lambda to consume it

This month:

Migrate top 3 polling jobs to events
Add DLQs to all EventBridge rules
Implement event versioning
Monitor cost savings!

This quarter:

Migrate ALL polling to events
Implement event replay/archive
Use EventBridge Pipes for integrations
Become the event-driven guru on your team! 🏆

Resources Worth Your Time 📚

Tools I use daily:

EventBridge Sandbox - Test patterns visually
EventCatalog - Document your events
AWS SAM - Deploy event-driven apps

Reading list:

Real talk: The best event-driven architecture starts with ONE event. Don't try to migrate everything at once. Start small, prove value, expand!

Still polling like it's 1999? Connect with me on LinkedIn and share your event-driven war stories!

Want to see my EventBridge architectures? Check out my GitHub - production event-driven examples!

Now go forth and publish some events! 📡✨

P.S. If you're checking a database every 5 seconds "just in case," you're doing it wrong. EventBridge can send you a notification the INSTANT something happens. For FREE (first 1M events). Stop wasting money on polling! 💸

P.P.S. I once forgot to add a DLQ to a critical EventBridge rule. When the Lambda failed, we lost $50K worth of orders. Support was... not happy. Learn from my pain - ALWAYS add DLQs! 🚨