Go lint (golangci-lint) — (errcheck) / (govet) / (staticcheck)

Log signatures

main.go:12:6: Error return value is not checked (errcheck)
app.go:8:2: this value of err is never used (ineffassign)
util.go:30:1: exported function should have comment (revive)
(staticcheck)
(govet)

What’s happening

golangci-lint aggregates many linters; each finding ends with the source linter in parentheses — file.go:12:6: ... (errcheck) — and that suffix is your triage key. The ones that are nearly always real bugs: (errcheck) — an ignored error return (the canonical Go landmine); (govet) — suspicious constructs like misformatted struct tags or copied locks; (staticcheck) correctness checks. The ones that are style: (gofmt), (revive), (gosimple). (ineffassign) and (unused) sit in between — often refactor residue, occasionally a sign that logic got disconnected.

Fix playbook

1. 1Reproduce at CI's golangci-lint version — finding sets change a lot between releases; a version mismatch means you're fixing a different report.
2. 2Sort findings by linter. Fix errcheck/govet/staticcheck as bugs: handle the error, don't _ = it away unless ignoring is genuinely correct (then say why in a comment).
3. 3gofmt findings: just run gofmt -w / golangci-lint run --fix.
4. 4False positives: //nolint:lintername // reason at the line — the reason is mandatory in spirit; a bare nolint is a future "why is this here."
5. 5Rerun golangci-lint run ./... locally before pushing.