Migrations

Contento uses Drizzle ORM with a migration-first workflow. Migrations are SQL files generated from the schema and applied explicitly — never via db:push.

Workflow

1. Change the schema

Edit src/lib/db/schema.ts.

2. Generate the migration

pnpm db:generate

This creates a new SQL file in drizzle/ — e.g. drizzle/0003_add_transform_cache.sql. Commit this file alongside the schema change.

3. Apply the migration

pnpm db:migrate

In Docker Compose, the migrate service does this automatically before contento-app starts:

migrate:
  build:
    context: .
    dockerfile: Dockerfile
    target: builder
  command: ["pnpm", "db:migrate"]
  environment:
    DATABASE_URL: ${DATABASE_URL}
  restart: "no"

contento-app has depends_on: migrate: condition: service_completed_successfully, so migrations always run before the app accepts traffic.

Migration files

Generated files live in drizzle/. They are:

• Committed to version control — they are the authoritative record of schema history
• Never edited manually — always re-generate if you change the schema
• Idempotent via Drizzle's journal — drizzle/__drizzle_migrations tracks what's been applied

Rolling back

Drizzle does not support automatic rollback. To revert a migration:

1. Write a new migration that undoes the change (pnpm db:generate after reverting the schema)
2. Apply it with pnpm db:migrate

Never delete migration files from drizzle/ — this corrupts the migration history.