Sign exact webhook bytes with versioned verification metadata
Partners cannot verify signatures after the sender serializes the same event differently on retry.
- Focused work estimate
- 2h 30m + prerequisites
- Priority in the scenario
- High
- Engineering practice
- Webhook security
Estimated field mix
- Security70%
- API design30%
Field percentages are editorial estimates of the ticket's engineering focus. They total 100%; they are not measured time, proficiency scores, or ownership evidence.
Review it, then add it to your workspace.
The board opens an editable draft; nothing is saved until you confirm it. Sign-in and workspace permissions apply, and Demo boards remain ephemeral.
Project context
A fictional logistics platform sends shipment events to partner endpoints. Partners need stable schemas and recovery semantics despite duplicate delivery, failures, and subscription changes.
Setup prerequisites
- Create a local webhook sender and receiver doubles with synthetic shipment events and disposable signing keys.
Preceding work
Complete these dependencies, or supply their agreed outputs before taking this ticket.
Acceptance criteria
- Sign the exact delivered bytes.
- Include key identity and bounded timestamp semantics.
- Document receiver verification before payload trust.
Implementation constraints
- Use generated test keys and never log signing material.
Verification to include
- Verify a valid local delivery.
- Change one byte or timestamp and reject verification.
Deliverables
- Signing contract and receiver example.
Rollout and recovery
Introduce a versioned signature format with a bounded rotation overlap.
Value of the work
For the engineer: Practice public event contracts, delivery guarantees, and partner recovery workflows.
For the team: Provide inspectable asynchronous integration behavior with controlled retries and clear compatibility.
Evidence boundaries
Outcome Evidence: Tests, patches, and runbooks are requested deliverables. They become Outcome Evidence only through a qualified Mission and immutable Evidence IDs.
Ownership Evidence: Independent adaptation must be observed under a declared verification policy and cite immutable Evidence IDs. Completing a planning ticket establishes no Ownership Evidence.