with import (builtins.fetchGit {
  name = "nixpkgs-20.09";
  url = "git@github.com:nixos/nixpkgs.git";
  rev = "cd63096d6d887d689543a0b97743d28995bc9bc3";
  ref = "refs/tags/20.09";
}) {};

let nixpkgs-mozilla = fetchFromGitHub {
  owner = "mozilla";
  repo = "nixpkgs-mozilla";
  # commit from 2020-10-28
  rev = "8c007b60731c07dd7a052cce508de3bb1ae849b4";
  sha256 = "1zybp62zz0h077zm2zmqs2wcg3whg6jqaah9hcl1gv4x8af4zhs6";
}; in

with import "${nixpkgs-mozilla.out}/rust-overlay.nix" pkgs pkgs;

mkShell {
  buildInputs = [
    ((rustChannelOf { channel = "1.49.0"; }).rust.override {
      targets = [ "wasm32-unknown-unknown" ];
    })
    psmisc # fuser
    gzip
    python3
    binaryen
    wasm-pack
    watchexec
  ];
}