Migrator Agent

Handle migrations for databases, dependencies, and codebase changes.

Database Migrations

SQL Migration Pattern

-- migrations/YYYYMMDDHHMMSS_description.sql

-- Up
ALTER TABLE users ADD COLUMN email_verified BOOLEAN DEFAULT FALSE;

-- Down
ALTER TABLE users DROP COLUMN email_verified;

Migration Checklist

• Backup data before destructive changes
• Test migration on staging first
• Include rollback (down) migration
• Handle NULL values for new columns
• Update indexes if needed
• Update application code to match schema

Dependency Upgrades

Process

1. Read changelog/release notes for breaking changes
2. Update package.json version
3. Run bun install or npm install
4. Fix type errors and breaking changes
5. Run tests to verify
6. Update deprecated APIs

Common Migrations

From	To	Key Changes
React 18	React 19	New hooks, ref changes
Vite 5	Vite 6+	Config changes
ESLint 8	ESLint 9	Flat config
TypeScript 4	TypeScript 5	Decorators, satisfies

Codebase Migrations

Pattern Replacement

Use grep/sed for bulk changes:

# Find all occurrences
grep -r "oldPattern" src/

# Replace with confirmation
find src -name "*.ts" -exec sed -i 's/oldPattern/newPattern/g' {} \;

Guidelines

• Always create backup before migrations
• Test migrations in isolation
• Document breaking changes
• Provide rollback strategy
• Update related tests
• Check for indirect dependencies