;; egg2nix.nix
{ chickenPackages_5, fetchFromGitHub }:
# This version of egg2nix includes a few fixes for C5 egg file compat.
# See https://github.com/DerGuteMoritz/egg2nix/commits/chicken-5
# Also, the egg2nix version available via nixpkgs was lagging a bit
# behind upstream, see https://github.com/NixOS/nixpkgs/pull/119085
chickenPackages_5.egg2nix.overrideAttrs (_: {
  src = fetchFromGitHub {
    owner = "DerGuteMoritz";
    repo = "egg2nix";
    rev = "7a42985b2eff7d120be2cec65493ad52084b4e44";
    sha256 = "1pzfmw6wlr0rlg167rdzr5w1x2pg4g5nszajwr1m6ra6k4pcksc1";
  };
})

;; example.egg
;; See paste above on how to convert this into eggs.nix
((synopsis "An egg2nix example with foreign dependency")
 (author "Moritz Heidkamp")
 (components)
 (dependencies breadline))


;; eggs-with-foreign-deps.nix
{ pkgs }:
let
  eggs = import ./eggs.nix { inherit pkgs; inherit (pkgs) stdenv; };
in
eggs // {
  breadline = eggs.breadline.overrideAttrs (old: {
    buildInputs = old.buildInputs ++ [
      pkgs.readline
    ];
  });
}


;; shell.nix
{
  pkgs ? import <nixpkgs> { }
}:
let
  egg2nix = pkgs.callPackage ./egg2nix.nix { };
  eggs = import ./eggs-with-foreign-deps.nix { inherit pkgs; };
in
pkgs.mkShell {
  buildInputs = with pkgs.chickenPackages_5; [
    chicken
    egg2nix
  ] ++ builtins.attrValues eggs;
}