[Nix-dev] gem nix writes sha256 = "no hash"

[Marc Weber]

ruby nix overlay:
1) ruby script to dump rubyforge to .nix files (50.000 packages)
   So no, I'm not going to ask to include them to nixpkgs.

2) nix code which generates nix derivations on the fly from the dump.

3) a bash script you can source to augment your shell env so that all
  packages are found.

4) some info about additional "C dependencies" which gets merged in.
Useful for accessing mysql, etc.

Problems:
- If you need very latest packages you have to rerun the dump (its experimental)
- If you need git based dependendies you might be in trouble
- If there are multiple versions of a package, you have to select a
  version eventually.

Great:
Its fast, because the dump is already there

Example:


      emproxyCollection =
          let ro = (pkgs.overlay "ruby");
          in ro.rubyEnv19 {
            name = "emproxy";
            p = {
            };
            names = [
              "eventmachine"
              "rspec"
              "em-http-request"
              "ansi"
              "rake"
              "posix-spawn"
            ];
          };

Problem: The versions might be little bit different from what bundlers
suggests.

If you want to know whether it solves your problem let me create an SSH
account on my server and grant you access (ping me on irc).

Then you can give it a try easily. Otherwise use the gem command (some
work with C dependencies) or fix the the tool causing trouble to you.

Marc Weber