Investigate ways to speed up Ruby builds

[RDIL]

Currently, building Ruby from source takes > 2 minutes. This is way too long. The scope of this issue is to investigate ways that this can be sped up.

Perhaps we need to pre-build modern ruby versions with YJIT, targeting Railpack's base image?

[iloveitaly]

Yeah, I'd love this as well. I looked into this, here are some notes:

• mise, which is what railpack is using under the hood for runtime installs, can use ruby-install or ruby-build
• ruby-install does not support binary installs
• ruby-build does not seem to support these either
• Seems like RVM supports binary installs, but this does not look to be supported by mise right now.
  • The binary builds available via RVM seem to pretty limited and not updated frequently.

The maintainer of mise stated:

In Python the astral team is working on portable binaries we use in mise. People have attempted this with Ruby but nobody is currently maintaining an active project for portable ruby

@RDIL this is all to say, it seems like there isn't a reliable way for using binary builds with ruby. Am I missing something here?

The only alternative, which you mentioned, is building a new base image for each ruby version (this could work, but I'd need to think about it more as it's a big departure from how other languages are managed).

[RDIL]

@iloveitaly my thinking was that we could maintain pre-built versions targeting the Railpack base image. That way you get the best of both worlds. It could always fall through to using Mise if a pre-build is not available, but my thinking is that if there were pre-builds of the most common versions, it shouldn't be that big of a problem.

[iloveitaly]

@RDIL Yup, that makes sense. I'll chat with the team about this one: this does seem like the best option that's available, but it would be a departure from how every other language is setup (and therefore some additional maintinance + complexity). I'll get back to you on this!

[coffee-cup]

Agree it is slow which sucks. I think there are a few options

• Platforms like Railway could specify cache layers using --cache-from and maintain a set of built "vanilla" images with the latest Ruby binaries preinstalled
• Use a custom base image for Ruby that pulls from the official ruby images on DockerHub. Similar to PHP
• Copy the built binaries directly from the official Ruby images. Similar to composer