Guides
Guides for integration tests from real API traffic
Practical writing on test fixtures, API privacy, and developer workflows. Written for backend and QA engineers who care about how the sausage gets made.
Understand the problem
Realistic test fixtures without production data
Hand-written fixtures rot; copying production data is a compliance liability. Three approaches to realistic test fixtures, and the trade-offs each one forces.
Masking PII in API test data: a practical guide
What actually counts as PII in request/response payloads, why shape-preserving masking matters for tests, and where in your pipeline masking must happen.
GDPR: can you use production data in staging?
Personal data in staging is still personal data under GDPR. What purpose limitation and data minimisation actually require for non-production environments.
Why your API mocks drift from reality
Hand-written mocks are accurate on day one and silently wrong by month six. The specific drift modes, why green CI doesn't protect you, and how to fix it.
Compare approaches
VCR, Polly.js, nock and WireMock compared
An honest comparison of VCR, Polly.js, nock, and WireMock for record-and-replay API testing: recording model, replay fidelity, and the cleartext problem.
Recorded stubs vs. contract testing
Contract testing and recorded stubs catch different failures. What each actually verifies, where each breaks down, and how to run both in one CI pipeline.
How-to
Replaying API stubs in GitHub Actions
Run tests against real-traffic-shaped API stubs in CI, with no live third-party calls, no production secrets in your environment, and no flaky network.
Writing masking rules that fail closed
How to write Stubsmith masking rules that default to protecting data: field-family patterns, value-shape matching, and the fail-closed posture.