Writing SQL-Only Extensions for Postgres

Shaun Thomas writes an extension:

Recently at Postgres Conference 2026 in San Jose, I presented a talk called Let’s Build a Postgres Extension! Since that entire presentation was primarily focused on writing a C extension while exploring the Postgres source code, I only mentioned pure SQL extensions as an aside. But what’s more likely in the Postgres community in general: C devs, or people who know SQL?

It turns out that you can do a lot with functions, triggers, views, tables, and various other Postgres-native capabilities. The extension system doesn’t care whether the contents are compiled C or plain SQL. It just wants a control file, a SQL script, and an optional Makefile to help with installation.

So let’s build a relatively trivial extension article entirely in SQL.

It’s a fairly neat capability, for sure.