Buildable Python development environment shell in Nix

default.nix

with import <nixpkgs> {};
stdenv.mkDerivation rec {
  name = "env";
  # Mandatory boilerplate for buildable env
  env = buildEnv { name = name; paths = buildInputs; };
  builder = builtins.toFile "builder.sh" ''
    source $stdenv/setup; ln -s $env $out
  '';
  # Customizable development requirements
  buildInputs = [
    (python.buildEnv.override {
      ignoreCollisions = true;
      extraLibs = with pythonPackages; [
        pillow
      ];
    })
  ];
  # Customizable development shell setup
  shellHook = ''
    export SSL_CERT_FILE=${cacert}/etc/ssl/certs/ca-bundle.crt
  '';
}