{fetchgit}:
fetchgit {
  url = "https://github.com/mautrix/whatsapp";
  rev = "20e6d9e65903ae9e2b91bb81aa00c6cbe2ed3731";
  sha256 = "0mqq0xyjz6q9amhq2nx78kn4dd9r7badwbjyl0cx1bf8l7fms4a5";
  leaveDotGit = true;
}