Jylhis TypeScript skill index
Pick the topic and read its reference before writing or reviewing TypeScript / Node.js code.
| Topic | When to read | Reference |
|---|---|---|
| Code style | naming, ESM-first ("type": "module"), import order, barrel-export avoidance, const/readonly | references/code-style.md |
| Type system | generics with extends, conditional types, infer, satisfies, branded/opaque types, NoInfer, mapped types | references/type-system.md |
| Async | Promise, async/await, AbortController, Promise.all/allSettled, async iterators, p-limit, AbortSignal.timeout | references/async.md |
| Error handling | Error subclassing with prototype chain, cause, Result/neverthrow, AggregateError, narrowing unknown in catch | references/error-handling.md |
| Zod validation | runtime validation at trust boundaries (HTTP, env, config), safeParse, z.infer, refinements, discriminated unions, coercion |
references/zod.md |
| Node patterns | node:fs/promises, child_process spawn/execFile, streams pipeline, worker_threads, pino logging, graceful shutdown | references/nodejs-patterns.md |
| Formatting (Prettier) | .prettierrc, --check in CI, eslint-config-prettier, husky + lint-staged, Prettier 3 defaults | references/formatting.md |
| Linting (ESLint 9) | flat config (eslint.config.js), tseslint.config helper, typed linting (project: true), ignores, glob overrides | references/linting.md |
| Packaging | pnpm + workspaces, "type": "module", exports field, .ts extensions in imports, ESM-first publishing | references/packaging.md |
| Testing (Vitest) | describe/it/expect, vi.mock / vi.spyOn, test.extend fixtures, snapshots, watch mode, coverage, Jest migration | references/testing.md |
For TypeScript / Node security topics (command injection, prototype
pollution, XSS, SSRF, secrets, npm audit), use the security skill.
After reading the reference, follow its guidance for the task.