For separation of concerns/isolation, DBOS does all its bookkeeping in a separate Postgres database from your app database (documented here: https://docs.dbos.dev/explanations/system-tables).

And yes, you can absolutely run this locally as a library! The bottom half of the quickstart covers how to do it: https://docs.dbos.dev/explanations/system-tables Just use a local (or Docker) Postgres.