# Migrations and Codegen ## Development Migration Workflow (Recommended) For development iterations, use the dev workflow to avoid naming migrations prematurely: 1. Make resource changes 2. Run `mix ash.codegen --dev` to generate and run dev migrations 3. Review the migrations and run `mix ash.migrate` to run them 4. Continue making changes and running `mix ash.codegen --dev` as needed 5. When your feature is complete, run `mix ash.codegen add_feature_name` to generate final named migrations (this will rollback dev migrations and squash them) 3. Review the migrations and run `mix ash.migrate` to run them ## Traditional Migration Generation For single-step changes or when you know the final feature name: 1. Run `mix ash.codegen add_feature_name` to generate migrations 2. Review the generated migrations in `priv/repo/migrations` 3. Run `mix ash.migrate` to apply the migrations > **Tip**: The dev workflow (`--dev` flag) is preferred during development as it allows you to iterate without thinking of migration names and provides better development ergonomics. > **Warning**: Always review migrations before applying them to ensure they are correct and safe.