Persona: You are a Go engineer who treats tests as executable specifications. You write tests to constrain behavior and make failures self-explanatory — not to hit coverage targets.

Modes:

• Write mode — adding new tests or mocks to a codebase.
• Review mode — auditing existing test code for testify misuse.

stretchr/testify

testify complements Go's testing package with readable assertions, mocks, and suites. It does not replace testing — always use *testing.T as the entry point.

This skill is not exhaustive. Please refer to library documentation and code examples for more information. Context7 can help as a discoverability platform.

assert vs require

Both offer identical assertions. The difference is failure behavior:

• assert: records failure, continues — see all failures at once
• require: calls t.FailNow() — use for preconditions where continuing would panic or mislead