refactor: migrate linting to Oxlint

scripts/run-gates.spec.ts

@@ -42,6 +42,18 @@ function withPnpmEntrypoint<T>(action: () => T): T {
   }
 }
 
+function withEnv<T>(name: string, value: string | undefined, action: () => T): T {
+  const previous = process.env[name]
+  if (value === undefined) Reflect.deleteProperty(process.env, name)
+  else process.env[name] = value
+  try {
+    return action()
+  } finally {
+    if (previous === undefined) Reflect.deleteProperty(process.env, name)
+    else process.env[name] = previous
+  }
+}
+
 describe('gate graph validation', () => {
   it.each([
     'ci-primary',
@@ -96,6 +108,38 @@ describe('gate graph validation', () => {
   })
 })
 
+describe('Oxlint gate', () => {
+  it('uses the package script when no worker bound is configured', () => {
+    const subject = withEnv('DSH_OXLINT_THREADS', undefined, () =>
+      withPnpmEntrypoint(() => gatesForMode('ci-lint')[0]))
+
+    expect(subject).toMatchObject({
+      id: 'lint',
+      displayCommand: 'pnpm run lint',
+      command: process.execPath,
+      args: ['/private/pnpm.cjs', 'run', 'lint'],
+    })
+  })
+
+  it('passes the configured native thread bound to Oxlint', () => {
+    const subject = withEnv('DSH_OXLINT_THREADS', '4', () =>
+      withPnpmEntrypoint(() => gatesForMode('ci-lint')[0]))
+
+    expect(subject).toMatchObject({
+      id: 'lint',
+      displayCommand: 'pnpm exec oxlint . --threads=4',
+      command: process.execPath,
+      args: ['/private/pnpm.cjs', 'exec', 'oxlint', '.', '--threads=4'],
+    })
+  })
+
+  it('rejects a non-positive or non-integer native thread bound', () => {
+    expect(() => withEnv('DSH_OXLINT_THREADS', 'auto', () =>
+      withPnpmEntrypoint(() => gatesForMode('ci-lint'))))
+      .toThrow('DSH_OXLINT_THREADS must be a positive integer')
+  })
+})
+
 describe('Node 24 consumer graph', () => {
   it('owns the seven-command pool and orders restored-artifact consumers', () => {
     const subject = withPnpmEntrypoint(() => gatesForMode('ci-consumers'))

scripts/run-gates.ts

@@ -181,10 +181,6 @@ function pnpmInvocation(args: string[]): Pick<Gate, 'command' | 'args'> {
   return { command: process.execPath, args: [entrypoint, ...args] }
 }
 
-function nodeOptions(...options: string[]): string {
-  return [process.env.NODE_OPTIONS, ...options].filter(option => option !== undefined && option !== '').join(' ')
-}
-
 /**
  * Construct the complete gate list for a named aggregate.
  * @param selected - aggregate mode to construct.
@@ -375,43 +371,22 @@ function ciWindowsObservationalGates(): Gate[] {
   ]
 }
 
-function lintGate(eslintTargets: readonly string[] = ['.']): Gate {
-  const concurrencyArgs = eslintConcurrencyArgs()
-  if (process.env.DSH_ESLINT_CACHE === '1') {
-    return pnpmExec('lint', [
-      'eslint',
-      ...eslintTargets,
-      ...concurrencyArgs,
-      '--cache',
-      '--cache-location',
-      '.cache/eslint/',
-      '--cache-strategy',
-      'content',
-    ], {
-      label: 'lint',
-      env: { NODE_OPTIONS: nodeOptions('--max-old-space-size=8192') },
-    })
+function lintGate(oxlintTargets: readonly string[] = ['.']): Gate {
+  const threadArgs = oxlintThreadArgs()
+  if (threadArgs.length > 0) {
+    return pnpmExec('lint', ['oxlint', ...oxlintTargets, ...threadArgs], { label: 'lint' })
   }
-  if (concurrencyArgs.length > 0) {
-    return pnpmExec('lint', ['eslint', ...eslintTargets, ...concurrencyArgs], {
-      label: 'lint',
-      env: { NODE_OPTIONS: nodeOptions('--max-old-space-size=8192') },
-    })
-  }
-  return pnpmScript('lint', 'lint', {
-    env: { NODE_OPTIONS: nodeOptions('--max-old-space-size=8192') },
-  })
+  return pnpmScript('lint', 'lint')
 }
 
-function eslintConcurrencyArgs(): string[] {
-  const raw = process.env.DSH_ESLINT_CONCURRENCY
+function oxlintThreadArgs(): string[] {
+  const raw = process.env.DSH_OXLINT_THREADS
   if (raw === undefined || raw === '') return []
-  if (raw === 'auto') return ['--concurrency=auto']
   const parsed = Number.parseInt(raw, 10)
   if (!Number.isSafeInteger(parsed) || parsed < 1 || String(parsed) !== raw) {
-    throw new Error(`run-gates: DSH_ESLINT_CONCURRENCY must be a positive integer or auto, got ${JSON.stringify(raw)}.`)
+    throw new Error(`run-gates: DSH_OXLINT_THREADS must be a positive integer, got ${JSON.stringify(raw)}.`)
   }
-  return [`--concurrency=${raw}`]
+  return [`--threads=${raw}`]
 }
 
 function coverageGate(): Gate {

scripts/test-invariants.ts

@@ -44,7 +44,7 @@ interface InvariantHost {
 type PluginFiber = ReturnType<RegistryService['plugin']>
 
 const hosts = new WeakMap<Context, InvariantHost>()
-// eslint-disable-next-line @typescript-eslint/unbound-method -- every call below supplies its RegistryService receiver explicitly.
+// oxlint-disable-next-line typescript/unbound-method -- every call below supplies its RegistryService receiver explicitly.
 const originalPlugin = RegistryService.prototype.plugin
 
 RegistryService.prototype.plugin = function(plugin: Plugin, config?: unknown, getOuterStack?: () => string[]) {

scripts/verify-export-jsdoc.ts

@@ -126,7 +126,7 @@ function heritageExemption(
           returnType = d.type.type
         } else continue
         baseParams ??= new Set()
-        // Leading underscores are the deliberately-unused marker (eslint
+        // Leading underscores are the deliberately-unused marker (lint
         // argsIgnorePattern), not a rename: `_cwd` overriding `cwd` is the
         // same parameter, so compare underscore-stripped on both sides.
         for (const p of params) if (ts.isIdentifier(p.name)) baseParams.add(p.name.text.replace(/^_+/, ''))