Advanced guides

As your Rails application becomes more popular, it will inevitably grow in complexity, the number of people using it will increase, and pretty much everything else goes up and to the right. Fortunately Fly can reduce some of that complexity by making global deployments easy and provide some best practices for scaling a Rails application on Fly.

Phusion Passenger

This guide shows you how to replace the Puma web server with nginx and Phusion Passenger.

Multiple Fly Applications

At some point a Rails application will need to run additional services, like a Puppeteer server that takes screenshots of a webpage for your Rails application. Learn how to manage multiple applications from one Rails project to keep your monolith a monolith.

Machine API

This guide shows use the Fly Machine API using Rails


This guide shows you how to use SQLite3 as your database


This guide shows use LiteFS with Rails

Multi-region Deployments

Architect Rails applications so they can run closer to your customers on servers deployed around the world.


This guide shows you how to replace Action Cable with AnyCable.