diff --git a/packages/simplexmq/example/simplexmq_example.dart b/packages/simplexmq/example/simplexmq_example.dart
index ef6b175bc5..e69de29bb2 100644
--- a/packages/simplexmq/example/simplexmq_example.dart
+++ b/packages/simplexmq/example/simplexmq_example.dart
@@ -1,39 +0,0 @@
-import 'dart:typed_data';
-
-import 'package:simplexmq/src/buffer.dart';
-import 'package:simplexmq/src/crypto.dart';
-import 'package:simplexmq/src/rsa_keys.dart';
-// import 'package:simplexmq/src/transport.dart';
-// import 'dart:io';
-// import 'package:rsa_pkcs/rsa_pkcs.dart' show RSAPKCSParser;
-// import 'package:pointycastle/asymmetric/api.dart';
-// import 'package:ssh_key/ssh_key.dart';
-
-void main() async {
-  // final socket = await Socket.connect('localhost', 8080);
-  // socket.add([65, 66, 67]);
-  // await socket.flush();
-  final keyStr =
-      // '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';
-      'MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAvV/IhWtgS1CENNl38Jo9mJqeJ63agN8zo2PAIHNxuorlFUpaXOkLtHcASn3PiXwjNgFuO2FtiP1QRIz7Cg8bACHtdsA20moUCnfExOgwhHsePCFxxcWTfPTeYqb83OJXKJdc3t0ihPD9Zo2o75BY6ahSiNY4NLQHEnuqCK+P/ItUDa7QqqzHcinlRPVgO7HbE/5YsGafd7McHVmd8dv0nild0y29SILXvGKOvHIkUBthb32VaCI+75b9A1eNvLdUlF0kSmWzQTLjSYwWVSvfP0zAetZ1vlksFaohYrSZUtZ0PlTkti1rdyCMdvLpsS2A6g3vjuobm0oUKiRgikNYywIDAQAB';
-  // final pair = RSAPKCSParser().parsePEM('''
-//   final key = publicKeyDecode('''
-// -----BEGIN PUBLIC KEY-----
-// MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAzknLODTvx9LrwnWrgoe5zSF7olPnp20O/0PLw/WtvV9paLzkeyhf07RqBzYUEyGccpOMEwY98SsJk/8GJnVPUclAHj2rqxAkwYTKHbsMjbZ18VuL0vC5JTBwnvqMUa+fj3oi7QxHMWLY9w1iYLauYM/aYWBc/Fg5LZoawG0Yf3nuZ3rGWic88tf5y8BIVgSEeRovF/NQKX8LsFgaxXdpTMfMwu7xVh0jaFUU98T6ke+GADszmuqeUXFs9IRZoRUieTSafM8XQ+Xr7g513TYTpXuj9GQ04nmE+BEZ5O2MBNjYFle91SsvCyPwYxv0aFbFZ05/vZKZIdbhgpFxh03p3wIDAQAB
-// -----END PUBLIC KEY-----
-// ''') as RSAPublicKey;
-  // final key = RSAPublicKey((pair.public?.modulus) as BigInt,
-  //     BigInt.from((pair.public?.publicExponent) as int));
-
-  final key = decodeRsaPubKey(decode64(encodeAscii(keyStr))!);
-  print(key);
-  final Uint8List header = encodeAscii('hello');
-  //  concatN([
-  //   encodeInt32(4096),
-  //   encodeInt16(0),
-  //   SessionKey.create().serialize(),
-  //   SessionKey.create().serialize()
-  // ]);
-  final enc = decodeAscii(encode64(encryptOAEP(key, header)));
-  print(enc);
-}
diff --git a/packages/simplexmq/lib/src/crypto.dart b/packages/simplexmq/lib/src/crypto.dart
index 5a184c1142..46fa8943a9 100644
--- a/packages/simplexmq/lib/src/crypto.dart
+++ b/packages/simplexmq/lib/src/crypto.dart
@@ -36,7 +36,6 @@ Uint8List pseudoRandomBytes(int len) {
   return _randomBytes(len, sessionSeed);
 }
 
-// len should be divisible by 4
 Uint8List _randomBytes(int len, Random seedSource) {
   final bytes = Uint8List(len);
   for (int i = 0; i < len; i++) {
@@ -81,13 +80,13 @@ AsymmetricKeyPair<RSAPublicKey, RSAPrivateKey> generateRSAkeyPair(
 }
 
 Uint8List encryptOAEP(RSAPublicKey key, Uint8List data) {
-  final oaep = OAEPEncoding(RSAEngine())
+  final oaep = OAEPEncoding.withSHA256(RSAEngine())
     ..init(true, PublicKeyParameter<RSAPublicKey>(key));
   return oaep.process(data);
 }
 
 Uint8List decryptOAEP(RSAPrivateKey key, Uint8List data) {
-  final oaep = OAEPEncoding(RSAEngine())
+  final oaep = OAEPEncoding.withSHA256(RSAEngine())
     ..init(false, PrivateKeyParameter<RSAPrivateKey>(key));
   return oaep.process(data);
 }
diff --git a/packages/simplexmq/lib/src/transport.dart b/packages/simplexmq/lib/src/transport.dart
index 3e9f0213e1..031c77672f 100644
--- a/packages/simplexmq/lib/src/transport.dart
+++ b/packages/simplexmq/lib/src/transport.dart
@@ -115,7 +115,6 @@ class SMPTransportClient {
 
   Future<void> _sendEncryptedKeys_4(RSAPublicKey serverKey) async {
     final header = encryptOAEP(serverKey, _clientHeader());
-    // print(header);
     await _conn.write(header);
   }
 
diff --git a/packages/simplexmq/pubspec.yaml b/packages/simplexmq/pubspec.yaml
index 5b90e7c3f9..479d90ebce 100644
--- a/packages/simplexmq/pubspec.yaml
+++ b/packages/simplexmq/pubspec.yaml
@@ -8,7 +8,12 @@ environment:
 
 dependencies:
   asn1lib: ^1.0.2
-  pointycastle: ^3.3.4
+  pointycastle:
+    git:
+      url: git@github.com:simplex-chat/pc-dart.git
+      ref: nullsafety
+
+  # pointycastle: ^3.3.4
 
 dev_dependencies:
   lints: ^1.0.0
diff --git a/packages/simplexmq_io/test/simplexmq_io_test.dart b/packages/simplexmq_io/test/simplexmq_io_test.dart
index dc2a5e1e9f..861ff3513a 100644
--- a/packages/simplexmq_io/test/simplexmq_io_test.dart
+++ b/packages/simplexmq_io/test/simplexmq_io_test.dart
@@ -12,7 +12,7 @@ void main() {
   group('transport', () {
     Future<ServerSocket> startServer(
         void Function(Socket client) handleConnection) async {
-      var server = await ServerSocket.bind(localhost, 5223);
+      var server = await ServerSocket.bind(localhost, 8080);
       server.listen(handleConnection);
       return server;
     }
@@ -21,14 +21,13 @@ void main() {
       var completer = Completer<Uint8List>();
 
       var server = await startServer((Socket client) {
-        print('client connected');
         client.listen(
           (Uint8List data) async {
             completer.complete(data);
           },
         );
       });
-      var transport = await SocketTransport.connect(localhost, 5223);
+      var transport = await SocketTransport.connect(localhost, 8080);
       await transport.write(Uint8List.fromList([1, 2, 3]));
 
       expect(await completer.future, [1, 2, 3]);
diff --git a/packages/simplexmq_io/test/transport_test.dart b/packages/simplexmq_io/test/transport_test.dart
index d5bb789d45..11a68b89bc 100644
--- a/packages/simplexmq_io/test/transport_test.dart
+++ b/packages/simplexmq_io/test/transport_test.dart
@@ -5,13 +5,14 @@ import 'package:test/test.dart';
 
 void main() {
   group('SMP transport', () {
-    test('establish connection (expects SMP server on localhost:5223)',
-        () async {
-      // await Socket.connect('localhost', 5223);
-      final conn = await SocketTransport.connect('localhost', 5223);
-      final smp = await SMPTransportClient.connect(conn);
-      print('connected');
-      print(smp);
-    }, skip: 'requires server; pc OAEP impl is not compatible as it uses SHA1');
+    test(
+      'establish connection (expects SMP server on localhost:5223)',
+      () async {
+        final conn = await SocketTransport.connect('localhost', 5223);
+        final smp = await SMPTransportClient.connect(conn);
+        expect(smp is SMPTransportClient, true);
+      },
+      skip: 'requires SMP server on port 5223',
+    );
   });
 }