Fire EventBridge events without touching real AWS
Thrubit intercepts every PutEvents call in your state machines and Lambda functions — returning instant, correctly-shaped mock responses.
ZERO real event routing. Zero latency. Zero downstream side-effects.
Every EventBridge call during testing triggers real downstream rules and targets
Before Thrubit, every test run of a state machine that fires PutEvents dispatches real events to your real event bus — triggering Lambda targets, SQS queues, and downstream workflows you're not ready to test yet.
Real events. Real side-effects. Real mess.
Every iteration fires real events into your event bus, triggering live targets — Lambda functions run, SQS messages pile up, downstream workflows execute. You're testing one thing but side-effecting a dozen others, and your test data pollutes production event streams.
Intercepted locally. Zero downstream noise.
Flip the EventBridge mock toggle. Every PutEvents call — from native Step Functions integrations or from inside your Lambda — is intercepted and returns a correctly-shaped EventId response instantly. No real routing, no side-effects, no event bus pollution.
Switch between real and mock EventBridge in seconds
The EventBridge mock is a global setting in Thrubit's AWS panel. Turn it on and every PutEvents call — whether from a Step Functions native integration (arn:aws:states:::events:putEvents) or from inside a Lambda function via the SDK — is intercepted immediately. No code changes. No environment variables.
- Works for both Step Functions native EventBridge integrations and direct SDK calls inside Lambda
- All
PutEventscalls — regardless of target event bus — are intercepted under the same toggle - Switch back to real AWS routing at any time without restarting or redeploying
- Intercepted events are logged inline in the execution output with their source, detail-type, and bus name
"Entries": [{
"Source":
"com.myapp.orders",
"DetailType":
"OrderPlaced",
"EventBusName":
"custom-bus",
"Detail": "{...}"
}]
}
"FailedEntryCount":
0,
"Entries": [{
"EventId":
"mock-a8f2-..."
}]
}
Mock responses that match the real EventBridge schema
Thrubit doesn't return a generic placeholder. The mock PutEvents response matches exactly what real EventBridge returns — so your ResultSelector mappings and downstream state transitions work correctly without touching a real event bus.
FailedEntryCount: 0and a validEntriesarray — exactly what a successful realPutEventscall returns- Each entry in the response includes a unique mock
EventId— downstream states that extract or log the ID work correctly - Batch
PutEventswith multiple entries returns correctly-sized response arrays - Your
ResultSelectorpaths andResultPathmerge patterns work identically against real and mock responses
Mocks wherever EventBridge is called — state machine or Lambda
EventBridge appears in two places in modern Step Functions architectures: as a native service integration in the ASL, and as a direct SDK call inside a Lambda function. Thrubit intercepts both.
- ASL-level
arn:aws:states:::events:putEventstask states are intercepted by the execution engine before any network call is made - Lambda-side calls via
AWS.EventBridge.putEvents()are patched at the SDK prototype level before your handler runs - The same shaped responses are returned in both paths —
ResultSelectormappings and handler parsing code both work correctly - No changes to your Lambda code required — the mock is injected transparently into the isolated Lambda process
ASL Native Integrations
events:putEvents- Default event bus
- Custom event buses
- Partner event buses
- Cross-account buses
- Batch entry payloads
Direct SDK Calls
EventBridge.putEvents()- v2 SDK (
@aws-sdk/client-eventbridge) - v3 SDK
PutEventsCommand - AWS SDK v2 class calls
- Callback & promise styles
- Async/await patterns
Every EventBridge pattern your workflows use
Thrubit handles the full range of PutEvents call patterns — from simple single-event publishes to complex multi-entry batches with custom routing keys.
FailedEntryCount: 0 and a single-item Entries array with a mock EventId.Entries array sized to match the input — so downstream index-based selectors work correctly.Source and DetailType fields you send — they're logged in the execution output so you can verify your routing keys without firing real events.Catch and Retry configurations without injecting real failures. The mock always succeeds — letting you verify happy-path routing before switching to live validation.Up and running in under a minute
No code changes, no environment variables, no AWS credentials required to use mock mode.
In Thrubit, open the Settings panel and navigate to the AWS tab. You'll see the EventBridge mock toggle alongside SQS, Bedrock, and your AWS profile and region configuration.
Flip the EventBridge toggle from "Real AWS" to "Mock". The change takes effect immediately — no restart needed. Run your state machine just as you normally would.
Every PutEvents call returns a correctly-shaped mock response in milliseconds with zero real routing. Verify your event payload structure, test downstream state transitions, and iterate without polluting your event bus.
When you're ready to validate real event routing, toggle back to "Real AWS" and run again. Because your response parsing was working against the correctly-shaped mock, it works live too.
Stop flooding your event bus every time you test.
Download Thrubit and run your first EventBridge-integrated state machine locally in under five minutes — with zero real event routing and instant, correctly-shaped mock responses.
What teams are saying
Real feedback from engineers, trainers and decision makers.
“Thrubit cut our Step Functions debugging cycle from 15 minutes per iteration down to seconds. The visual trace is worth the price alone. It’s become an essential part of our development workflow.”
“I was looking for ways to make Step Functions and Lambdas more tangible for students. Thrubit makes it significantly easier to visualize workflows and experiment locally, accelerating real understanding.”
“Thrubit saves us over $24k a year & protects us from surprise AWS bills. One rogue state machine once cost us 10x our typical month. With Thrubit, that risk is gone and our developers iterate faster.”
