Event id mutated by middleware Debugging Lab

Event id mutated by middlewareEvents & ConcurrencyEasyPreparing workspaceAutosaved

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Incident Dossier

Event id mutated by middleware

Webhook retries for the same payment.succeeded event still trigger duplicate side effects. The raw event body is identical between deliveries, but the dedupe layer cannot recognise the second arrival as the same event.

Initial failing signalRetry of an enriched webhook is not dedupedExpected ingest(enrichedRetry) returns false · received ingest(enrichedRetry) returns true

Progress

1Reproduce the bugRun checks

2Edit the fixOpen

3Pass checksOpen

4Submit fixOpen

Reproduction Steps

Run npm test.
Look at how the dedupe key is derived from the parsed event.
Notice that the signature middleware mutates the payload before ingest.
Switch to a stable fingerprint that ignores middleware-added fields.

Focus Mode

Start

src/ingest.js

Likely area

src/ingest.js

Progressive hints

Hints reveal broad direction first, then narrow toward the suspect path without showing hidden tests or exact solution code.

TopicEvents & Concurrency

DifficultyEasy

Est. time14 min

Workspacecreating

Explorer

Preparing workspace files…

Evidence Map

Failing signal loaded from challenge API
Workspace files loaded from workspace API
Results rendered only after API run/submit

Autosaved

workspace

Outputread-onlyready$ workspace boot

Workspace booting...