Self-hosted migrations

Plan a migration

npx @c15t/cli@alpha self-host migrate --config ./c15t-backend.config.ts --plan --json

The CLI reads the database option from the config file, loading .env from the file's directory, and reports what it would change. --plan changes no schema. Without --config, the CLI looks for c15t-backend.config.ts; in a terminal it can help you create one.

A v2 config that only has adapter fails with a message naming the field. Replace it with database, as the database setup guide shows.

Apply it

npx @c15t/cli@alpha self-host migrate --config ./c15t-backend.config.ts --apply --json

--apply is the only flag that writes. Without --plan or --apply, a terminal shows the plan and asks before applying; a script must pass one of them. --json alone never applies a migration.

The result reports planned, applied, already current or cancelled work. A database the migrator does not recognize fails with an explanation instead of being changed. The CLI closes its database connection when it finishes, also on failure.

Back up the database before applying against existing data, and run the migration against the same database and schema the server uses. Codemods do not migrate a database.