[oleg2025]

FastAPI pattern works very well with Pgbouncer, when it is in transaction pool mode.

Your Python application maintains a connection to Pgbouncer during the lifecycle of the request, but the physical Postgres connection is allocated only during the DB transaction. You will need open/close transactions in your code though.

[frollogaston]

This is why I said PgBouncer is a sign of something being wrong. Devs aren't managing connections right, they try to paper over it with PgBouncer, it's not really easier cause they now need to be conscious of xacts instead, and now there's an extra moving part in the DB that most of the team doesn't really understand. PgBouncer has its other uses, but I really don't like this one.

I also get it, xact should be 1:1 with connection in a lot of these backend applications. Sometimes I have a few little helpers for that, like pool.sql() will take conn, open xact, execute, close xact, return conn. If the DB driver doesn't already have that.