It is a bit of a pain to test something out in development where you want isolated sessions. It is a common need to log in with two different users - the alternative being that you log in with the first user, do something, log out, log in with the other user, and then do something. Many people solve this by having a regular browser session and another incognito mode session. With Puma-dev this can be done pretty easily.

I’ve come to enjoy using Puma-dev for Rails apps I work on regularly. Basically you would access an app called myapp by going to http://myapp.test.
An added benefit over using rails s and accessing your app on http://localhost:3000 is that Puma-dev handles subdomains. So in addition to http://myapp.test you can also access your app via http://www.myapp.test, http://www2.myapp.test, etc. And because each subdomain by default will have separate cookies we get the ability to have multiple sessions open in the same browser. Recalling the common need of multiple users, you could log the first user in via http://www1.myapp.test and the other user via http://www2.myapp.test - all in the same browser window.

Easy! 🎉