Amazing project that spawned entire companies. We used it to build postgresml[0] and most Postgres extensions are built on top of it these days.

[0] https://github.com/postgresml/postgresml

I built https://github.com/k0nserv/plid with Pgrx and had a great time. I did have to scale back some of the magic (dropping derive PostgresType etc), but even so the support pgrx provides is excellent. I also talked to the maintainers a bit in discord and they were super helpful.

The one downside of custom extensions is that you aren’t, AFAIK, able to use them with many hosted Postgres installs, notably AWS RDS.

I thought this was abandoned?

Supabase is an interesting middle ground here — it runs on managed Postgres but gives you access to a curated set of extensions (pg_cron, pgvector, unaccent, PostGIS etc.) without needing to build your own. We used unaccent + GIN indexes for fuzzy city search and it worked well. Still not the same as arbitrary custom extensions, but covers a lot of practical use cases that RDS won't touch.