Bundix doesn't work with the ruby option in the Gemfile if bundix is built with a different ruby version

[edude03]

So I've been having a weird issue were I couldn't use bundix inside of nix shell using a bundlerEnv.

I'd get an error like couldn't find gem ruby 2.7.2 found 2.6.6 (going from memory, sorry).

Anyway, while debugging a different issue with bundix (why I had both ruby 2.6 and 2.7 in my closure) I found out the bundix derivation has a ruby option. Passing ruby = pkgs.ruby_2_7 into bundix makes this issue go away, which makes me assume bundix is using it's own version of ruby when bundling thus why it can't find the version of ruby the app is using.

I'm not sure if there is a better fix other than passing bundix the same version of ruby as your bundlerEnv, but I figured I'd open an issue to hopefully spark discussion or at least help people running into the same issue

[vmsp]

For anyone, like myself, who stumbles on this issue, you can do this:

nix-shell -p "ruby_3_0" -p "bundix" --run "bundle lock && bundix --ruby=ruby_3_0"