What problem did you have? I had an issue getting an RoR project running on NixOS, but it was just a lack of understanding. I needed Ruby 2.7.4 for the project,

What problem did you have? I had an issue getting an RoR project running on NixOS, but it was just a lack of understanding. I needed Ruby 2.7.4 for the project, which is not available in current nixpkgs. Instead, I just imported the nixpkgs tarball with 2.7.4 and I was good to go. I found it by searching ruby_2_7_4 on hydra.nixos.org