Did something change recently with what versions of libpq-dev are published to buster-pgdg? We have a dockerfile based on postgres:12.2 (which is based on buster-slim) that installs "libpq-dev=$PG_MAJOR.*" and it just recently (this week) started failing. running a brand new postgres container and checking the apt cache, I only see versions for 11 (coming from debian sources) and 13 (coming from buster-pgdg main). I have verified that the sources list includes both main and 12 -- was it removed from 12?