nixpkgs/pkgs/development/interpreters/elixir/generic-builder.nix

{ pkgs, stdenv, fetchFromGitHub, erlang, rebar, makeWrapper,
  coreutils, curl, bash, debugInfo ? false }:

{ baseName ? "elixir"
, version
, minimumOTPVersion
, sha256 ? null
, rev ? "v${version}"
, src ? fetchFromGitHub { inherit rev sha256; owner = "elixir-lang"; repo = "elixir"; }
} @ args:

let
  inherit (stdenv.lib) getVersion versionAtLeast;

in
  assert versionAtLeast (getVersion erlang) minimumOTPVersion;

  stdenv.mkDerivation ({
    name = "${baseName}-${version}";

    inherit src version;

    buildInputs = [ erlang rebar makeWrapper ];

    LANG = "C.UTF-8";
    LC_TYPE = "C.UTF-8";

    setupHook = ./setup-hook.sh;

    inherit debugInfo;

    buildFlags = if debugInfo
      then "ERL_COMPILER_OPTIONS=debug_info"
      else "";

    preBuild = ''
      # The build process uses ./rebar. Link it to the nixpkgs rebar
      rm -vf rebar
      ln -s ${rebar}/bin/rebar rebar

      patchShebangs lib/elixir/generate_app.escript || true

      substituteInPlace Makefile \
        --replace "/usr/local" $out
    '';

    postFixup = ''
      # Elixir binaries are shell scripts which run erl. Add some stuff
      # to PATH so the scripts can run without problems.

      for f in $out/bin/*; do
       b=$(basename $f)
        if [ "$b" = mix ]; then continue; fi
        wrapProgram $f \
          --prefix PATH ":" "${stdenv.lib.makeBinPath [ erlang coreutils curl bash ]}" \
          --set CURL_CA_BUNDLE /etc/ssl/certs/ca-certificates.crt
      done

      substituteInPlace $out/bin/mix \
            --replace "/usr/bin/env elixir" "${coreutils}/bin/env elixir"
    '';

    pos = builtins.unsafeGetAttrPos "sha256" args;
    meta = with stdenv.lib; {
      homepage = https://elixir-lang.org/;
      description = "A functional, meta-programming aware language built on top of the Erlang VM";

      longDescription = ''
        Elixir is a functional, meta-programming aware language built on
        top of the Erlang VM. It is a dynamic language with flexible
        syntax and macro support that leverages Erlang's abilities to
        build concurrent, distributed and fault-tolerant applications
        with hot code upgrades.
      '';

      license = licenses.epl10;
      platforms = platforms.unix;
      maintainers = with maintainers; [ the-kenny havvy couchemar ankhers ];
    };
  })