/bun

Complete Bun lifecycle management. Audit → Plan → Execute → Verify.

What This Does

• Run comprehensive Bun compatibility audit

• Determine migration scope (full, hybrid, or skip)

• Execute migration steps via /fix-bun iterations

• Verify complete migration

• Benchmark performance improvement

• Update documentation

Process

1. Assess Current State

Run /check-bun to get full audit:

/check-bun

Review the output for:

• P0 Blockers: If any exist, recommend SKIP or HYBRID

• P1 Essential: Must fix before migration

• Migration complexity: LOW, MEDIUM, or HIGH

• Recommendation: PROCEED, HYBRID, or SKIP

2. Determine Migration Scope

PROCEED (Full Migration)

• No blockers

• Platform supports Bun

• Team ready for Bun

HYBRID (Partial Migration)

• Platform limitations (Expo, Vercel serverless)

• Keep pnpm for production apps

• Use Bun for internal tools/scripts

SKIP (Not Recommended)

• Critical blockers exist

• Platform doesn't support Bun

• Migration cost exceeds benefit

3. Interview (If Needed)

Use AskUserQuestion to clarify:

• Migration scope preference (full vs hybrid)

• Timeline constraints

• Specific concerns about Bun

4. Create Migration Branch

git checkout -b chore/bun-migration

5. Execute Migration

For PROCEED scope:

Fix issues in priority order

/fix-bun # P1: Lockfile cleanup /fix-bun # P1: CI migration /fix-bun # P1: Workspace migration /fix-bun # P2: Script updates /fix-bun # P2: Test runner

For HYBRID scope:

Keep pnpm for apps, set up Bun for tools:

Main monorepo stays pnpm

Add Bun for specific directories

mkdir -p tools/scripts cd tools/scripts && bun init

6. Verification Checklist

After migration, verify everything works:

1. Clean install

rm -rf node_modules bun install

2. Type checking

bun run typecheck # or tsc --noEmit

3. Linting

bun run lint

4. Tests pass

bun test

5. Build succeeds

bun run build

6. Dev server works

bun run dev & sleep 10 curl -f http://localhost:3000 > /dev/null && echo "✓ Dev server works" kill %1

7. Performance Benchmark

Compare against pnpm baseline:

Baseline (before migration, on main branch)

git stash time pnpm install --force 2>&1 | tail -1 time pnpm run build 2>&1 | tail -1 time pnpm test 2>&1 | tail -1 git stash pop

Bun (on migration branch)

time bun install --force 2>&1 | tail -1 time bun run build 2>&1 | tail -1 time bun test 2>&1 | tail -1

8. Update Documentation

Update README.md:

Development

This project uses Bun for package management and script execution.

Prerequisites

• Bun 1.1.0+ (install: curl -fsSL https://bun.sh/install | bash)

Setup

```bash bun install bun run dev ```

Update CONTRIBUTING.md (if exists):

Package Manager

This project uses Bun. Do not commit pnpm-lock.yaml or package-lock.json.

```bash bun install --frozen-lockfile bun test ```

9. Commit and PR

git add -A git commit -m "chore: migrate to Bun package manager

• Replace pnpm with Bun for package management
• Update CI to use oven-sh/setup-bun
• Migrate workspace configuration to package.json
• Update documentation

Performance improvement:

• Install: Xms → Yms (Z% faster)
• Build: Xms → Yms (Z% faster)
• Test: Xms → Yms (Z% faster)

Co-Authored-By: Claude <noreply@anthropic.com>"

Output Report

Bun Migration Complete

Scope

[FULL/HYBRID]

Changes Made

• ✓ Removed pnpm-lock.yaml, added bun.lock
• ✓ Updated CI to use oven-sh/setup-bun
• ✓ Migrated workspace config to package.json
• ✓ Updated scripts to use bun run
• ✓ Updated documentation

Performance Results

Verification

• ✓ Clean install succeeds
• ✓ Type checking passes
• ✓ Linting passes
• ✓ All tests pass
• ✓ Build succeeds
• ✓ Dev server works

Next Steps

1. Review and merge PR
2. Update any external CI/CD configs
3. Notify team of tooling change

Rollback Procedure

If migration fails:

Revert to pnpm

git checkout main rm -rf node_modules bun.lock bun.lockb pnpm install

Related

• /check-bun

• Audit for Bun compatibility

• /fix-bun

• Fix one Bun issue at a time

• /bun-best-practices

• When to use Bun (reference)