Quality Gates

What are Quality Gates?

Quality gates are shell commands that run after an agent makes changes. They enforce lint, type checks, tests, and any other deterministic validation.

quality_gates:
  - "bun test"
  - "bunx tsc --noEmit"
  - "bun run lint"

File-Attribution

Quality gates run against the full project, but Tack only fails a stream for errors in its own files.

Stream 1 (backend):  bunx tsc --noEmit → fails on frontend error → PASS (not in scope)
Stream 2 (frontend): bunx tsc --noEmit → fails on frontend error → FAIL (in scope)

Pre-existing errors in other files don't block progress. Cross-file breakage is caught at merge time when post-merge gates run against the combined result.

Fix-Loops

When gates fail for errors in the stream's file scope, Tack sends the errors back to the builder agent with a "fix this" instruction. The agent iterates until gates pass or the max iteration limit is reached.

- id: lint
  type: deterministic
  action: run_quality_gates
  retry: 2
  on_fail: build
  max_fix_iterations: 3

Post-Merge Gates

After streams are merged, quality gates run again against the merged result. This catches integration issues that individual streams couldn't detect.