# Flip primitive to `native`

This PR changes one or more `crypto.config.ts` entries from `'noble'` to
`'native'`. Landing a flip permanently swaps the repo's routing for the
primitive — every consumer picks up the in-house implementation on the
next build.

Do not merge this PR without every box checked. Dangerous-tier primitives
(curves, AEADs, argon2id) additionally require a linked audit document.

## Primitive(s) affected

<!-- List each flipped primitive and its new flavour. -->
- [ ] `<primitive-id>`: `noble` → `native`

## Gate 1 — KAT (known-answer tests)

- [ ] All vectors pass on the new impl.
- [ ] Link to the KAT run:
  <!-- paste CI link for `bunx turbo crypto:kat` -->

## Gate 2 — Differential fuzz history

- [ ] At least 7 consecutive nightly `crypto:fuzz` runs pass native-vs-noble
  with zero mismatches.
- [ ] Link to the 7-day nightly history:
  <!-- paste CI dashboard link -->

## Gate 3 — Timing report

- [ ] `crypto:timing` run for this primitive reports `constantTime: true`
  against the default threshold (t < 4.5).
- [ ] Link to the timing report:
  <!-- paste artifact link -->

## Audit document (dangerous tier only)

Required for: `secp256k1`, `ed25519`, `x25519`, `p256`, `aes-256-gcm`,
`chacha20-poly1305`, `xchacha20-poly1305`, `argon2id`.

- [ ] N/A — primitive is not dangerous tier.
- [ ] Audit document linked below. Include: reviewer name, scope, findings,
  sign-off date.
  <!-- link to audit doc -->

## Rollback plan

- [ ] Reverting `crypto.config.ts` and regenerating selects restores `noble`
  routing with zero other changes.
- [ ] Legacy noble impl at `impl/<id>.noble.ts` is untouched by this PR.

## Checklist

- [ ] `bun scripts/gen-crypto-selects.ts` has been run and `<id>.select.ts`
  has been updated to re-export from `./impl/<id>.native.js`.
- [ ] `bun scripts/check-crypto-selects.ts` is green.
- [ ] `bun scripts/ct-lint.ts` is green.
- [ ] `bunx turbo lint typecheck test` is green across every crypto-*
  package.