How do I move an app from SQLite to Postgres?

Create the schema in Postgres, import the data into Supabase, and only then switch the app to the new connection string. A SQLite file lives on one machine’s disk, so once your app runs on more than one server or on serverless functions, it needs a database server it can reach over the network.

Most ORMs support both databases, so the app side is usually small: switch the provider or dialect to Postgres and read the connection string from an environment variable. Generate fresh migrations for Postgres rather than reusing the SQLite ones, because a few types behave differently. Booleans stored as integers should become boolean, and dates stored as text should become timestamptz. SQLite also accepts values that don’t match a column’s type, and Postgres won’t, so clean those up first.

If the app runs as a single process on one machine and nobody else needs the data, SQLite may still be the simpler choice.