title: How to implement service with it's own authentication
body: <p>What's the best practice for implementing something like 'MatterMost', a slack-like service for messaging, with my own frontend/backend.</p>
  <p>They use an email and a password for logging the user in and then an access token for verifying the user, and my question is what's the most seamless way of implementing something like this with my own project where i already have a whole authentication system set up.</p>
  <p>Do i just register/login the user in the background manually or is there a better way to go about this?</p>