Extend the base recipe to configure SSH
Compile cookbooks with "berks vendor"
Add the yum cookbook

... so we'll be able to add a /etc/yum.repos.d file for PostgreSQL 9.3.
Compile cookbooks with "berks vendor"
Add the postgresql cookbook
Add the PostgreSQL 9.3 yum repo
Include postgresql in the appropriate recipes
Compile cookbooks with "berks vendor"