This goal of this project lets you include local sources in your Nix projects, while taking gitignore files into account.

Note that although this project does a good job at emulating git's behavior, it is not the same implementation!

nix-env -iA niv -f https://github.com/nmattia/niv/tarball/master
niv init
niv add hercules-ci/gitignore

let
  gitignoreSrc = pkgs.fetchFromGitHub { 
    owner = "hercules-ci";
    repo = "gitignore";
    # put the latest commit sha of gitignore Nix library here:
    rev = "";
    # use what nix suggests in the mismatch message here:
    sha256 = "sha256:0000000000000000000000000000000000000000000000000000";
  };
  inherit (import gitignoreSrc { inherit (pkgs) lib; }) gitignoreSource;
in
  <your nix expression>

mkDerivation {
  name = "hello";
  src = gitignoreSource ./vendored/hello;
}

• Reads parent gitignores even if only pointed at a subdirectory
• Source hashes only change when output changes
• Not impacted by large or inaccessible ignored directories
• Composes with cleanSourceWith
• Reads user git configuration; no need to bother your team with your tool config.
• Also works with restrict-eval enabled (if avoiding fetchFromGitHub)
• No import from derivation ("IFD")

Please open a PR if you've found another feature, determined any of the '?' or found an inaccuracy!

This project isn't perfect (yet) so please submit test cases and fixes as pull requests. Before doing anything drastic, it's a good idea to open an issue first to discuss and optimize the approach.

A great shoutout to @siers for writing the intial test suite and rule translation code!