I'm not sure which db libs you've looked at, but the most used one is https://github.com/clojure/java.jdbc and it's just a wrapper for the Java JDBC API. The Postgres/MySQL connections are managed by the official org.postgresql/postgresql and mysql/mysql-connector-java driver libraries.

HugSQL hasn't seen much development, because it works well. I'm using it in all my projects, and it's been working perfectly for me. The library has a fixed feature set, which is taking SQL templates and generating functions that make JDBC calls based on them. Now that it's feature complete, the only time you'd see changes would be if the underlying API changed, or for a bugfix. The last commit actually happened 28 days ago, and it was a bump in dependencies.

Just because the repo isn't active is not an indication that the library is abandoned. My experience with Clojure libraries, is that this is usually an indication that the library works well and most bugs have been ironed out. Looking through the issues is generally a better approach of checking the health of the project I find.

If stability of database connection libraries has been your concern, I can assure you that it's misplaced.