# Qwik Optimizer Development

> Use when modifying or reviewing the Qwik optimizer under packages/optimizer, Rust transform code, WASM/NAPI bindings, optimizer snapshots, or optimizer-facing runtime behavior.

- Skill: `qwikdev/qwik-optimizer-development` (Agent Skill)
- Install (CLI): `npx skillmds@latest add qwikdev/qwik-optimizer-development`
- Raw SKILL.md: https://api.skillmd.com/api/skills/qwikdev/qwik-optimizer-development/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: qwikdev (https://skillmd.com/u/qwikdev)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/qwikdev/qwik-optimizer-development

---


# Qwik Optimizer Development

Use this skill for `packages/optimizer/**` and Rust optimizer work. Keep the repo-wide rules from
`.ruler/AGENTS.md` in force.

## Fast Path

1. Identify whether the change is Rust transform logic, snapshots, WASM bindings, NAPI bindings, or
   TypeScript optimizer-facing integration.
2. Read the closest Rust source, fixture, snapshot, and runtime helper that consumes the emitted
   shape before editing.
3. Keep transform behavior deterministic: prefer explicit parser/AST cases and stable ordering over
   source-text heuristics.
4. Use Rust-focused verification first; use `pnpm build.full` only when a full optimizer/WASM rebuild
   is required.
5. If a runtime/core change is also involved, load `qwik-core-development` for that slice.

## Source Map

- Rust optimizer core: `packages/optimizer/core/src/`
- Rust fixtures: `packages/optimizer/core/src/fixtures/`
- Rust snapshots: `packages/optimizer/core/src/snapshots/`
- WASM bindings: `packages/optimizer/wasm/`
- NAPI bindings: `packages/optimizer/napi/`
- Optimizer package entry points: `packages/optimizer/src/`
- Vite/Rollup integration: `packages/qwik-vite/src/`

## Verification

Use the smallest command that covers the change:

```bash
pnpm test.rust
pnpm test.rust.update
pnpm build.full
pnpm vitest run packages/qwik-vite/src/plugins/plugin.unit.ts
```

`pnpm test.rust` maps to `make test`, which runs Cargo tests for
`packages/optimizer/core/Cargo.toml`. Use `pnpm test.rust.update` only when snapshot updates are
intentional.

## Hard Rules

- Do not hand-edit generated optimizer build output in `dist/`, `lib/`, or `target/`.
- Do not update snapshots without understanding the transform behavior change.
- Add or update a transform fixture/snapshot for every optimizer behavior change, including negative
  cases where the transform must not run.
- Keep optimizer output and runtime JSX/QRL/loader semantics in sync. If a transform changes an
  emitted attribute, import, segment, or capture shape, inspect the runtime consumer too.
- After touching `packages/optimizer/core/`, do not claim verification without Rust test/build
  evidence or a recorded blocker.
- If this skill becomes stale after source inspection, update it before finishing or record why
  guidance edits were out of scope.