[fny]

As far as I'm aware, the port of pg 0.17.1 is alive and well: https://github.com/headius/jruby-pg

[ghufran_syed]

Is there any guidance out there about when to use activerecord-jdbc-adapter vs this gem (for postgres)?

[headius]

In general everything ActiveRecord does should be supported by JDBC. The pg port is for cases where you need features the JDBC driver does not support but the C driver does, like geocoding etc.