/fix-bun

Fix one Bun migration issue at a time. Verify after each change.

What This Does

1. Run /check-bun to get current findings
2. Pick highest priority unfixed issue
3. Apply fix
4. Verify fix worked
5. Report what was fixed

This is a fixer. It fixes ONE issue per invocation. Run multiple times for multiple issues.

Priority Order

Fix issues in this order:

1. P1: Lockfile cleanup — Remove conflicting lockfiles
2. P1: CI migration — Update GitHub Actions to use Bun
3. P1: Workspace migration — Move workspaces to package.json
4. P2: Script updates — Convert scripts to use bun run
5. P2: Test runner — Enable Bun test runner
6. P3: Optimizations — Native SQLite, Bun shell scripts

Fix Procedures

Fix: Remove Conflicting Lockfiles

When: Both pnpm-lock.yaml and bun.lock exist

# Choose one lockfile (keep the target one)
rm pnpm-lock.yaml  # If migrating to Bun
# OR
rm bun.lock bun.lockb  # If staying with pnpm

# Regenerate
bun install  # OR pnpm install

Verify:

ls *.lock* | wc -l  # Should be 1

Fix: Update CI to Bun

When: GitHub Actions using pnpm/action-setup

File: .github/workflows/ci.yml (or similar)

Change:

# From:
- uses: pnpm/action-setup@v4
- uses: actions/setup-node@v4
  with:
    cache: 'pnpm'
- run: pnpm install --frozen-lockfile

# To:
- uses: oven-sh/setup-bun@v2
  with:
    bun-version: latest
- run: bun install --frozen-lockfile

Verify:

grep -l "oven-sh/setup-bun" .github/workflows/*.yml

Fix: Migrate Workspace Configuration

When: pnpm-workspace.yaml exists but migrating to Bun

Step 1: Add workspaces to package.json

{
  "workspaces": ["apps/*", "packages/*"]
}

Step 2: Remove pnpm workspace file

rm pnpm-workspace.yaml

Step 3: Update packageManager field

{
  "packageManager": "bun@1.1.0"
}

Step 4: Reinstall

rm -rf node_modules
bun install

Verify:

[ ! -f "pnpm-workspace.yaml" ] && echo "✓ Workspace file removed"
grep -q '"workspaces"' package.json && echo "✓ Workspaces in package.json"
bun pm ls  # List workspaces

Fix: Update npm Scripts

When: Scripts explicitly use node where bun would work

Change in package.json scripts:

{
  "scripts": {
    // From:
    "start": "node dist/index.js",
    "dev": "ts-node src/index.ts",

    // To:
    "start": "bun dist/index.js",
    "dev": "bun src/index.ts"
  }
}

Verify:

bun run dev  # Should work
bun run start  # Should work

Fix: Enable Bun Test Runner

When: Using Jest but Bun test runner would work

Step 1: Update test script

{
  "scripts": {
    "test": "bun test"
  }
}

Step 2: Verify Jest-compatible syntax works

bun test

Note: Bun test runner is Jest-compatible. Most tests work without changes.

If Vitest: Can use Bun runner:

{
  "scripts": {
    "test": "vitest run"
  }
}

Verify:

bun test  # All tests pass

Fix: Update .gitignore

When: Migrating lockfile format

# Add/update in .gitignore
echo "# Bun" >> .gitignore
echo "bun.lockb" >> .gitignore  # Binary lockfile (optional, some prefer text)

# Remove old lockfile from gitignore if needed
sed -i '' '/pnpm-lock.yaml/d' .gitignore

Verify:

cat .gitignore | grep -E "bun|pnpm"

Verification Checklist

After any fix:

# 1. Install works
bun install

# 2. Build works (if applicable)
bun run build

# 3. Tests pass
bun test

# 4. Dev server starts (if applicable)
bun run dev &
sleep 5
curl http://localhost:3000 > /dev/null && echo "✓ Dev server works"
kill %1

Output Format

## Fixed: [Issue Title]

**What was wrong**:
[Brief description]

**What was changed**:
- [File]: [Change description]

**Verification**:
- ✓ bun install succeeds
- ✓ bun test passes
- ✓ [Other relevant checks]

**Next issue (if any)**:
Run /fix-bun again to fix: [Next P1/P2 issue]

Related

• /check-bun – Audit for Bun compatibility
• /bun – Full Bun migration orchestrator
• /bun-best-practices – When to use Bun (reference)