using crypto libraries with dart2js

Question

I'm facing a challenge when using https://pub.dev/packages/dart_jsonwebtoken with Firebase Functions.

I used this article to enable Firebase Functions with Dart code, but when it comes to using crypto libraries, I'm getting following error:

Error: Value of "this" must be of type nullish or must be the global object

Here's sample code I'm using:

Future<void> simpleSign() async {
  String token;

  final jwt = JWT(
    {
      'id': 123,
      'server': {
        'id': '3e4fc296',
        'loc': 'euw-2',
      }
    },
    issuer: 'https://github.com/jonasroussel/dart_jsonwebtoken',
  );

  // Sign it
  final pem = rsaPrivKey;
  final key = RSAPrivateKey(pem);

  token = await jwt.sign(key, algorithm: JWTAlgorithm.RS256);

  print('Signed token: $token\n');
}

I'd appreciate any ideas how to move forward. I want to use this feature to create JWS for further usage.