Rails Supported Versions?

Is Rails 7 the only version supported? There’s very little mention in the docs but trying to get anything but a vanilla rails 7 app going on fly.io has been impossible for me, including rails 6 apps upgraded to rails 7 that run locally fine and also run on heroku fine.

The crux of the issue with the few various apps I’ve tried seems to be that assets:precompile fails because the bundled gem environment doesn’t seem to be available.

Before I dig into it further I figure I might as well ask if any versions older than rails 7 will even work on fly.io, or if I’m just wasting time trying to get them to work and should head elsewhere. Thanks!

I’ve used Heroku · Launch on Fly.io to migrate my rails apps and all seems good for me.

ruby '2.7.2'
gem 'rails', '~> 6.0'

I’m running Rails 5.1 without any issues

I’ve run both Rails 6 and Rails 7 without much issue.

I could be wrong here. But I feel like fly.io’s use of Docker would make it so the version wouldn’t matter. Theoretically – all versions of ruby & rails are compatible with fly.io.