#mocks

Testing & QA Bug Report

All unit tests passed and the release failed in production: our mock had drifted from the real API

Leila Farahani · Nov 6, 2026 · 7 min read

A shipping integration had 96 percent coverage and a green build. In production, every label request failed, because the carrier API returned a field as a nested object while our mock returned a string. Why mocks drift, the difference between mocks and fakes, and the checks that keep test doubles honest.

DevOps & CI/CD

Testing Terraform modules with terraform test: plan-mode unit tests, mocks and real applies

Isabel Ferreira · Dec 7, 2024 · 7 min read

Our shared Terraform modules broke consumers twice in one quarter. We added terraform test: fast plan-mode tests with mocked providers on every pull request, and a nightly apply-mode suite against a sandbox account. The test layout, what to assert, and what it costs.