PostMaster is a beautiful web application to manage domains, users, and aliases on a Linux mail server. After setting up a Linux mail server using the guide from DigitalOcean or Linode, you start to see how tedious it can be to write raw SQL queries to add a new user to your Linux mail server. PostMaster abstracts the domain, user, and alias management of your mail server into a responsive web interface, that is both simple to use and secure.
Although PostMaster was built to work with the database schema instructed in the DigitalOcean or Linode guides, paid support is available for the developers of PostMaster to customize it to work in your environment.
PostMaster is written by Kevin Law and Matthew Prahl.