let deps = {
      "haskell.nix" = builtins.fetchTarball {
        url = "https://github.com/input-output-hk/haskell.nix/archive/d8c50dcaf3d3d589829ee9be9d5dba8279b8cc59.tar.gz";
        sha256 = "0a5hgryz6nszmy67yf1aks399h2aw0nj845518c4prs5c6ns1z7p";
      };
    };

    haskellNix = import deps."haskell.nix" {};

    # Import nixpkgs and pass the haskell.nix provided nixpkgsArgs
    pkgs = import
      # haskell.nix provides access to the nixpkgs pins which are used by our CI,
      # hence you will be more likely to get cache hits when using these.
      # But you can also just use your own, e.g. '<nixpkgs>'.
      haskellNix.sources.nixpkgs-unstable
      # These arguments passed to nixpkgs, include some patches and also
      # the haskell.nix functionality itself as an overlay.
      haskellNix.nixpkgsArgs;

    project = pkgs: pkgs.haskell-nix.project {
      src = ./.;

      shell.withHaddock = if pkgs.stdenv.hostPlatform.isGhcjs then false else true;

      # Specify the GHC version to use.
      compiler-nix-name = "ghc910"; # Not required for `stack.yaml` based projects.
    };

in {
  ghc = project pkgs;
  ghc-js = project pkgs.pkgsCross.ghcjs;
}

let projects = import ./default.nix;
    project = projects.ghc;
in project.shellFor {
  tools = {
    cabal = "latest";
  };

  buildInputs = with project.pkgs; [
    nodejs-slim_latest
  ];

  # Sellect cross compilers to include.
  crossPlatforms = ps: with ps; [
    ghcjs # Adds support for `javascript-unknown-ghcjs-cabal build` in the shell
  ];
}