prisma-composer-core-concepts

Declare the dependency with `deps: { db: rawPostgres() }` or `postgres(dataContract)` in the service, then wire it at `provision()` in the parent module. The service reads the binding via `service.load()`, receiving `{ url }` or `{ url, client }` respectively.

Edit `contract.prisma`, run `prisma contract emit`, then `prisma migration plan --name <slug>` to author the migration, and commit `migrations/` before deploying. Deploys are replay-only and refuse with `MIGRATION_PATH_NOT_FOUND` if no authored path reaches the target contract.

Composer mints per-binding service keys at deploy, and `serve()` rejects any caller that is not a wired consumer with 401. This is expected behavior, not a broken deploy; debug through a wired consumer or locally where nothing is enforced.

Use `mockService` from `@prisma/composer/testing` to substitute typed dependency doubles and input values, or `bootstrapService` from `@prisma/composer-prisma-cloud/testing` to boot the real built entry against a chosen config over real HTTP.

The alchemy engine pins an exact `effect` version, and a hoisted different version from your app halts every command. Match your app's `effect` to Composer's pin or force it with package.json `overrides`, then reinstall.

RPC over HTTP is the only contract kind; there is no gRPC, WebSocket, or streaming support, and no in-memory bindings without HTTP. The CLI also has no interactive login, authenticating deploys only via a static `PRISMA_SERVICE_TOKEN`.