A working local screen is only one observation. Webhooks cross an untrusted network boundary; API clients outlive one release; browser journeys expose failures invisible to unit tests; and performance measurements vary by device and route. These topics turn integration claims into explicit contracts with failure injection and measured evidence.
Topics in this track
- Signed Webhook Delivery and Replay Control — Verify raw event bytes, reject old deliveries, and process duplicates safely.
- API Evolution and Compatibility Windows — Change a response contract without breaking clients that still use the old shape.
- Browser Journey and Fault-Injection Tests — Test a user task through navigation, request, response, and visible recovery.
- Field and Lab Performance Evidence — Separate controlled diagnosis from the conditions real visitors experience.
Prerequisite paths
Tests across boundaries: assert behavior, not implementation text; Observability: connect user failure to a safe request trace; Page performance: budget the critical path and reserve layout space.
Neighbor track
Identity and Application Security.
Practice path
Build Project: webhook contract and browser verification and check decisions in Web Development: identity and integration contracts quiz.
Further connections
Quality and Capacity Engineering.