diff --git a/bin/ci-gates.js b/bin/ci-gates.js
index 715f50f29a..ee5595f861 100644
--- a/bin/ci-gates.js
+++ b/bin/ci-gates.js
@@ -5,19 +5,29 @@
 //
 // `job` is the workflow job id (the key under `jobs:`), which is stable, unlike
 // the rendered display name (matrix jobs interpolate `${{ ... }}`).
+//
+// pre-ci gates may declare:
+//   command  — full-parity command (run by `pnpm pre-ci`)
+//   affected — faster command for `pnpm pre-ci:affected` (defaults to `command`)
+//   affectedWhen: 'codegen' — in affected mode, run only when the diff plausibly
+//     changes generated output; otherwise skip with a reminder.
+//
+// Affected commands base on `origin/main` (not the local `main` that nx's
+// defaultBase would use), matching the codegen/vitest change detection so all of
+// pre-ci:affected reasons about the same diff.
 
 export const CI_GATES = [
   // --- gates a contributor can reproduce locally before pushing ---
   // Ordered as pre-ci should run them: build precedes the oclif codegen check,
   // and the graphql check precedes the oclif check (their whole-repo `git status`
   // asserts otherwise cross-contaminate in a single working tree).
-  {job: 'type-check', kind: 'pre-ci', command: 'pnpm type-check'},
-  {job: 'lint', kind: 'pre-ci', command: 'pnpm lint'},
-  {job: 'bundle', kind: 'pre-ci', command: 'pnpm build'},
+  {job: 'type-check', kind: 'pre-ci', command: 'pnpm type-check', affected: 'pnpm exec nx affected --target=type-check --base=origin/main'},
+  {job: 'lint', kind: 'pre-ci', command: 'pnpm lint', affected: 'pnpm exec nx affected --target=lint --base=origin/main'},
+  {job: 'bundle', kind: 'pre-ci', command: 'pnpm build', affected: 'pnpm exec nx affected --target=build --base=origin/main'},
   {job: 'knip', kind: 'pre-ci', command: 'pnpm knip'},
-  {job: 'graphql-schema', kind: 'pre-ci', command: 'pnpm codegen:check:graphql'},
-  {job: 'oclif-checks', kind: 'pre-ci', command: 'pnpm codegen:check:oclif'},
-  {job: 'unit-tests', kind: 'pre-ci', command: 'pnpm test'},
+  {job: 'graphql-schema', kind: 'pre-ci', command: 'pnpm codegen:check:graphql', affectedWhen: 'codegen'},
+  {job: 'oclif-checks', kind: 'pre-ci', command: 'pnpm codegen:check:oclif', affectedWhen: 'codegen'},
+  {job: 'unit-tests', kind: 'pre-ci', command: 'pnpm test', affected: 'pnpm vitest run --changed origin/main'},
 
   // --- CI-only jobs, with the reason they are not part of pre-ci ---
   {
diff --git a/bin/pre-ci.js b/bin/pre-ci.js
index e148a35d30..7b56f1e325 100644
--- a/bin/pre-ci.js
+++ b/bin/pre-ci.js
@@ -1,21 +1,89 @@
-// Runs the local subset of PR CI gates ("run what CI runs") so contributors can
-// catch failures before pushing. The gate list and its parity with the workflow
-// are defined in bin/ci-gates.js and enforced by bin/check-ci-gates.js.
+// Runs the local PR CI gates ("run what CI runs") so contributors can catch
+// failures before pushing. The gate list and its parity with the workflow are
+// defined in bin/ci-gates.js and enforced by bin/check-ci-gates.js.
 //
-// pre-ci mirrors CI's full (`--all`) targets so that green locally implies green
-// in CI. It is intentionally slower than the affected-only `dev check`.
+//   pnpm pre-ci            full parity with CI's `--all` targets (slower)
+//   pnpm pre-ci:affected   only what your diff touches (faster inner loop)
+//
+// Affected mode runs the nx/vitest affected variants and skips the codegen
+// freshness checks unless the diff plausibly changes generated output.
 import {execSync} from 'node:child_process'
 
 import {PRE_CI_GATES, CI_ONLY_GATES} from './ci-gates.js'
 
-const steps = [
-  {label: 'CI gate manifest in sync', command: 'pnpm check-ci-gates'},
-  ...PRE_CI_GATES.map((gate) => ({label: gate.job, command: gate.command})),
-]
+const affected = process.argv.includes('--affected')
+
+// git may wrap paths with special chars in quotes; strip them.
+function unquote(path) {
+  return path.replace(/^"(.*)"$/, '$1')
+}
+
+// Changed files vs the merge-base with origin/main, plus the working tree.
+// Returns null if detection fails, so callers can fail safe (assume relevant).
+function changedFiles() {
+  try {
+    const base = execSync('git merge-base HEAD origin/main', {encoding: 'utf8'}).trim()
+    const committed = execSync(`git diff --name-only ${base}..HEAD`, {encoding: 'utf8'})
+    const working = execSync('git status --porcelain', {encoding: 'utf8'})
+    const files = new Set()
+    for (const line of committed.split('\n')) {
+      const path = unquote(line.trim())
+      if (path) files.add(path)
+    }
+    for (const line of working.split('\n')) {
+      if (!line.trim()) continue
+      let entry = line.slice(3).trim()
+      if (entry.includes(' -> ')) entry = entry.split(' -> ').pop() // rename: keep the new path
+      files.add(unquote(entry))
+    }
+    return [...files]
+  } catch {
+    return null
+  }
+}
+
+function touchesGeneratedOutput(files) {
+  if (files === null) return true
+  return files.some(
+    (file) => file.includes('/commands/') || file.endsWith('.graphql') || /graphql/i.test(file) || file.startsWith('docs-shopify.dev/'),
+  )
+}
+
+// Affected mode bases on origin/main. Warn if the local main has drifted from it,
+// since that usually means origin/main is stale and the affected set may be off.
+function localMainDriftWarning() {
+  try {
+    const local = execSync('git rev-parse main', {encoding: 'utf8', stdio: ['pipe', 'pipe', 'ignore']}).trim()
+    const remote = execSync('git rev-parse origin/main', {encoding: 'utf8', stdio: ['pipe', 'pipe', 'ignore']}).trim()
+    if (local !== remote) {
+      return 'Local `main` differs from `origin/main` (affected mode bases on `origin/main`). Run `git fetch origin main` if the affected set looks off.'
+    }
+  } catch {
+    // No local `main` ref (e.g. a fresh worktree) — nothing to compare.
+  }
+  return null
+}
+
+const diff = affected ? changedFiles() : null
+const codegenRelevant = affected ? touchesGeneratedOutput(diff) : true
+
+const driftWarning = affected ? localMainDriftWarning() : null
+if (driftWarning) process.stdout.write(`\n⚠ ${driftWarning}\n`)
+
+const steps = [{label: 'CI gate manifest in sync', command: 'pnpm check-ci-gates'}]
+const skipped = []
+for (const gate of PRE_CI_GATES) {
+  if (affected && gate.affectedWhen === 'codegen' && !codegenRelevant) {
+    skipped.push({job: gate.job, reason: 'affected mode: diff does not touch commands, flags, or GraphQL'})
+    continue
+  }
+  const command = affected ? gate.affected ?? gate.command : gate.command
+  steps.push({label: affected ? `${gate.job} (affected)` : gate.job, command})
+}
 
 const results = []
 for (const step of steps) {
-  process.stdout.write(`\n▶ ${step.label}: ${step.command}\n`)
+  process.stdout.write(`\n\u25b6 ${step.label}: ${step.command}\n`)
   try {
     execSync(step.command, {stdio: 'inherit'})
     results.push({...step, ok: true})
@@ -24,19 +92,23 @@ for (const step of steps) {
   }
 }
 
-console.log('\n──────── pre-ci summary ────────')
-for (const result of results) {
-  console.log(`${result.ok ? '✓' : '✗'} ${result.label}`)
+console.log(`\n\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 pre-ci${affected ? ' (affected)' : ''} summary \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500`)
+for (const result of results) console.log(`${result.ok ? '\u2713' : '\u2717'} ${result.label}`)
+for (const gate of skipped) console.log(`\u00b7 ${gate.job} \u2014 skipped (${gate.reason})`)
+
+if (affected) {
+  console.log('\nAffected mode is a fast pre-push check, not full CI parity. Run `pnpm pre-ci` before a high-risk push.')
+  if (skipped.length > 0) {
+    console.log('If you changed commands, flags, or GraphQL queries, run `pnpm codegen` and commit the result.')
+  }
 }
 
 console.log('\nNot run locally (CI-only):')
-for (const gate of CI_ONLY_GATES) {
-  console.log(`· ${gate.job} — ${gate.reason}`)
-}
+for (const gate of CI_ONLY_GATES) console.log(`\u00b7 ${gate.job} \u2014 ${gate.reason}`)
 
 const failed = results.filter((result) => !result.ok)
 if (failed.length > 0) {
   console.error(`\npre-ci failed: ${failed.map((result) => result.label).join(', ')}`)
   process.exit(1)
 }
-console.log('\npre-ci passed. Note: codegen checks regenerate files — review `git status` for any uncommitted generated changes.')
+console.log('\npre-ci passed. Codegen checks regenerate files — review `git status` for uncommitted generated changes.')
diff --git a/dev.yml b/dev.yml
index 8f64660a55..3279632f30 100644
--- a/dev.yml
+++ b/dev.yml
@@ -69,6 +69,9 @@ commands:
   pre-ci:
     desc: 'Run the local subset of PR CI gates (run what CI runs) before pushing'
     run: pnpm run pre-ci
+  pre-ci:affected:
+    desc: 'Faster pre-ci limited to what your diff touches'
+    run: pnpm run pre-ci:affected
 
 check:
   type-check: pnpm nx affected --target=type-check
diff --git a/package.json b/package.json
index b53670b7e4..d953af68f5 100644
--- a/package.json
+++ b/package.json
@@ -31,6 +31,7 @@
     "release": "./bin/release",
     "post-release": "./bin/post-release",
     "pre-ci": "node bin/pre-ci.js",
+    "pre-ci:affected": "node bin/pre-ci.js --affected",
     "update-observe": "node bin/update-observe.js",
     "shopify:run": "node packages/cli/bin/dev.js",
     "shopify": "nx build cli && node packages/cli/bin/dev.js",