Integration Tests
Does the thing work when connected to its actual dependencies? Catches failures that unit tests structurally cannot see — connection failures, serialization mismatches, timeout behavior.
Sensor properties
| Property | Value |
|---|---|
| Oracle strength | High — failure means the integration is broken |
| Independence | Low — same team writes code and tests |
| Scope | Service-level |
| Feedback latency | Minutes |
| Actionability | Guiding — shows which integration point failed |
| Type | Predictive |
What it cannot detect
Integration tests with mock dependencies don’t test the real integration. They test your assumptions about the real integration. Contract tests are a stronger sensor for boundary assumptions.