I’ve read the Crystal for Rubyist wiki page, and this Reddit comment about some of the challenges. But I can also think of a lot of examples that could be easily automated and save some time: Rename all file extensions from .rb to .cr Translate methods / operators with different names, e.g.: i…

I decided to fork rufo and created a ruby_crystal_codemod repo on GitHub. Haha I just started working on a few of the easy changes, and then @asterite popped up in the git history! [06%20AM]

[image] ndbroadbent: Haha I just started working on a few of the easy changes, and then @asterite popped up in the git history! :laughing: I created rufo! It was previously under my github account but I eventually gave up: maintaining one big open source project is already a lot of work! …

Initial commit committed 07:19PM - 19 Jun 17 UTC (UTC) [asterite] asterite +431 -0 …

Oh that’s awesome, I didn’t realize that! I’m also interested in converting Crystal syntax to Ruby, and I posted about that here . My idea was just so that I could run some simple Crystal code using Ruby’s interpreter, so I would have access to a real REPL where I can modify variables and define new…

When I give talks on Crystal this idea comes up a lot. It would be really nice to point people to something like this even if it only covers basic libraries.

Wow I just realized that I could translate many Sorbet type annotations into Crystal type annotations! I’m definitely going to add that to the roadmap. I’d love to make it as easy as possible for some of the engineers at these companies to start looking into Crystal: [36 PM]

if anyone is interested the repo is here. [image] DocSpring/ruby_crystal_codemod A codemod / transpiler that can help you convert Ruby into Crystal - DocSpring/ruby_crystal_codemod

I’m not confident that this is a good idea, at least not until Crystal passes the 1.0 point. Like many people I started out thinking it would be great to convert programs between ruby and crystal. At first you pick a few small-ish programs and it seems like this would be easy and very useful. But…

@drosehn You’re probably right, but it’s been a lot of fun to work on! I think I will probably keep working on as a hobby project / academic exercise to learn more about the Crystal language. I added this special #~# BEGIN / END comment syntax (inspired by the Rufo test suite!), so it’s now possibl…

Although I don’t expect to directly translate a full app it could lead to a translator assistant for snippets and scripts. It can help for users migrating from Ruby to Crystal to learn the delta in a more interactive way rather than reading. It might be more interesting if the criteria of the diff…

Has anyone started working on a Ruby => Crystal codemod / transpiler / converter?

Community

straight-shoota Split this topic January 26, 2026, 12:36pm 13

A post was split to a new topic: Lexing Crystal for a Crystal to Ruby transpiler

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Has anyone started working on a Ruby => Crystal codemod / transpiler / converter?

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