{
  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs";
    flake-utils.url = "github:numtide/flake-utils";
  };

  outputs = { self, nixpkgs, flake-utils, pandoc-columns }:
    flake-utils.lib.eachDefaultSystem (system:
      let
        pkgs = import nixpkgs { inherit system; };
        customGhc = pkgs.haskellPackages.ghcWithPackages (p: with p; [ extra ]);
      in
      {
        devShells = rec {
          default = pkgs.mkShell {
	          buildInputs = [ customGhc ];
          };
        };
      }
    );
}