code-migration

# Code migration (six-step process) You are orchestrating a language migration using the Claude Code Migration Kit. [kit path]/README.md defines the process; [kit path]/CLAUDE.md defines your standing rules — read both before acting (set [kit path] when installing this skill). The standing rules override convenience: queues live on disk, sign-off gates end workflows, the rulebook is read-only inside loops, reviewers are adversarial and separate. ## Routing 1. **No migration artifacts exist yet** (`migration/` absent): run `prompts/00-feasibility.md`. Produce the report, deliver the verdict, STOP. Do not begin Step 1 in the same session, even if the verdict is "migrate now" — the human kicks off each phase. 1b. **Feasibility signed off, no judge yet:** before Step 1, confirm a judge exists that runs against both old and new code through the public surface. If the existing suite is public-surface (or already in a third language), it's the judge — carry it to Step 6. If it imports internals, run `prompts/00b-judge-setup.md` to build and validate a portable parity harness (validated against the original AND deliberately broken code) and STOP at its gate. Never start Step 1 without a judge — there's no exit condition without one. 2. **Feasibility and judge signed off, no map/rules:** run Step 1 — adapt a `scripts/depmap_*` for the source ecosystem (`prompts/01`), copy `templates/RULEBOOK.md` to `migration/RULEBOOK.md` and draft it with the human (the policy decisions are theirs; survey the codebase for the facts), then `prompts/02` for the gap inventory. Each ends at its own gate. 3. **Step 1 signed off:** confirm the HUMAN has installed `.claude/settings.json` from `templates/settings.json` — prompt 03 verifies it; never install it yourself — then run `prompts/03-stress-test.md`. But FIRST check the rulebook's §0 posture: if this is a redesign migration, the bakeoff is invalid; substitute adversarial design-doc review and tell the human why. 4. **Stress test signed off:** confirm `migration/manifest.tsv` exists (prompt 01's closing action generates it), then run `prompts/04-translation-kickoff.md` with `scripts/queue_runner.mjs` as the queue — first check the referee price: if the target's typecheck is cheap, the dissolve edit is the human's act at the gate — ask them to remove those denies from settings.json; never edit it yourself (README Step 4 dissolves into Step 3). 5. **Translation queue empty:** Step 4 via `prompts/05-survey-build.md` (survey build → machine queue → fixers without compiler access; skip it entirely if Step 4 dissolved into Step 3), then Step 5 (hello world, smoke), then Step 6 (inherited suite burndown, or parity referee against the old code). 6. **Step 6 done-gate passed** (both counts documented — README Step 6): run `prompts/06-post-parity.md` — collect the port markers, classify fix-now vs document-and-close, ship each fix as its own flagged change proved by a parity re-run. Ends at its own gate. ## Constant behaviors - Report progress as burndown numbers (`queue_runner.mjs status`), not prose. - A failure seen three times is a rule bug: stop fixing instances, queue the amendment, propose regenerating the slice. - "Don't migrate" and "stop here" are valid recommendations at every gate.