anchor.diff: -{ stdenv, lib, elixir, erlang, findutils, hex, rebar3, fetchMixDeps, makeWrapper, git }:
  +{ stdenv, lib, elixir, erlang, findutils, hex, rebar3, fetchMixDeps, makeWrapper, git, ripgrep }:
   
   { pname
   , version
  
positive.code:     # removing unused erlang reference from resulting derivation to reduce
      # closure size
      if [ -e $out/erts-* ]; then
        echo "ERTS found in $dir - removing references to erlang to reduce closure size"
        for file in $out/erts-*/bin/{erl,start}; do
          substituteInPlace "$file" --replace "${erlang}/lib/erlang" "$out"
        done
      fi
  
negative.code: in
  assert mixNixDeps != { } -> mixFodDeps == null;
  stdenv.mkDerivation (overridable // {
    # rg is used as a better grep to search for erlang references in the final release
    nativeBuildInputs = nativeBuildInputs ++ [ erlang hex elixir makeWrapper git ripgrep ];
    buildInputs = builtins.attrValues mixNixDeps;
  
    MIX_ENV = mixEnv;
  