let
  unstableTarball = fetchTarball
    "https://github.com/NixOS/nixpkgs/archive/nixos-unstable.tar.gz";
  pkgs = import <nixpkgs> { };
  unstable = import unstableTarball { };

in with pkgs;
pkgs.mkShell {
  name = "rust";
  buildInputs = [
    openssl
    pkg-config
    unstable.cargo
    unstable.rustc
    unstable.rustfmt
    unstable.rust-analyzer
    postgresql
  ];
}