let
  moz_overlay = import (builtins.fetchTarball https://github.com/mozilla/nixpkgs-mozilla/archive/master.tar.gz);
  nixpkgs = import <nixos-unstable> { overlays = [ moz_overlay ]; };
  rustNightlyChannel = (nixpkgs.rustChannelOf { date = "2021-01-01"; channel = "nightly"; }).rust.override {
    extensions = [
			"rust-src"
			"rls-preview"
			"clippy-preview"
			"rustfmt-preview"
		];
  };
	rustStableChannel = nixpkgs.latest.rustChannels.stable.rust.override {
		extensions = [
			"rust-src"
			"rls-preview"
			"clippy-preview"
			"rustfmt-preview"
		];
  };
in
with nixpkgs;
  stdenv.mkDerivation {
    name = "moz_overlay_shell";
    buildInputs = [
      rustNightlyChannel
      coz
      cargo-flamegraph
      cmake
      gcc
      llvm_11
    ];
  }