# postgres_engine_required

HTTP 409 · Plan counts (SPEC §3.1, §3.2)

This project uses D1, so it has no Postgres database. Move it to Postgres first.

## Does retrying help?

Not until something else changes. The message says what: a plan, an add-on, a setting or a role. The same request then works.

## The response

Every Flatstack error has this shape. `details`, when present, says more about this case.

```json
{
  "error": {
    "code": "postgres_engine_required",
    "message": "This project uses D1, so it has no Postgres database. Move it to Postgres first.",
    "docsUrl": "https://flatstack.dev/docs/errors/postgres_engine_required"
  }
}
```

[All error codes](/docs/errors)