Installing pg gem - Can't find the 'libpq-fe.h header
Make sure PostgreSQL is installed. Find the pg_config file: find / -name pg_config 2>/dev/null gem install pg --version '0.18.4' -- --with-pg_config=PATH_TO_PG_CONFIG In my case: gem install pg --version '0.18.4' -- --with-pg_config=/usr/lib/postgresql96/bin/pg_config