foundation

CI basics

Run deterministic install, lint, typecheck, tests, build, and artifact steps on every change before merge.

CI basics interviews test the verification ladder on every change: reproducible install, lint, semantic typecheck, layered tests, production build, and artifact retention. The goal is catching defects before merge with deterministic inputs.

Subtopics: install, lint, typecheck, tests, build, artifacts.

On interviews: design gates for a TypeScript monorepo—what runs in parallel, what needs artifacts, and why `npm ci` plus `tsc --noEmit` matter alongside Vite build.

Common pitfalls: trusting local `node_modules`; skipping typecheck because dev server works; no build step until deploy.

The trade-off is PR pipeline duration versus confidence that main stays releasable.

Checklist:

  • Enforce lockfile installs in CI.
  • Separate lint, typecheck, test, and build stages.
  • Publish artifacts for deploy and audit.
  • Parallelize only independent stages.