diff --git a/examples/posix/testing_nanopb.c b/examples/posix/testing_nanopb.c
index 79021558..4d70b61f 100644
--- a/examples/posix/testing_nanopb.c
+++ b/examples/posix/testing_nanopb.c
@@ -9,31 +9,37 @@
 
 int main() {
 
-  TaggedMessage original_message;
-  TaggedMessage deserialized_message;
+  FederateMessage msg;
+  FederateMessage deserialized;
+
+  msg.type = MessageType_TAGGED_MESSAGE;
+  msg.which_message = FederateMessage_tagged_message_tag;
+
+  TaggedMessage *original_message = &msg.message.tagged_message;
   unsigned char buffer[BUFFER_SIZE];
   unsigned char *message = NULL;
   int message_size = 0;
 
-  original_message.conn_id = MSG_ID;
+  original_message->conn_id = MSG_ID;
   const char *text = "Hello World1234";
-  memcpy(original_message.payload.bytes, text, sizeof("Hello World1234")); // NOLINT
-  original_message.payload.size = sizeof("Hello World1234");
+  memcpy(original_message->payload.bytes, text, sizeof("Hello World1234")); // NOLINT
+  original_message->payload.size = sizeof("Hello World1234");
 
   message = buffer;
-  message_size = encode_protobuf(&original_message, buffer, BUFFER_SIZE);
+  message_size = encode_protobuf(&msg, buffer, BUFFER_SIZE);
   if (message_size < 0) {
     printf("encoding failed!\n");
     exit(1);
   }
 
-  int remaining_bytes = decode_protobuf(&deserialized_message, message, message_size);
+  int remaining_bytes = decode_protobuf(&deserialized, message, message_size);
 
   if (remaining_bytes < 0) {
     printf("decoding failed!\n");
     exit(1);
   }
 
-  printf("o: %i d: %i\n", original_message.conn_id, deserialized_message.conn_id);
-  printf("o: %s d: %s\n", (char *)original_message.payload.bytes, (char *)deserialized_message.payload.bytes);
+  printf("o: %i d: %i\n", original_message->conn_id, deserialized.message.tagged_message.conn_id);
+  printf("o: %s d: %s\n", (char *)original_message->payload.bytes,
+         (char *)deserialized.message.tagged_message.payload.bytes);
 }
\ No newline at end of file
diff --git a/examples/posix/testing_posix_tcp_ip_channel_client.c b/examples/posix/testing_posix_tcp_ip_channel_client.c
index b795ffc2..38a3ce18 100644
--- a/examples/posix/testing_posix_tcp_ip_channel_client.c
+++ b/examples/posix/testing_posix_tcp_ip_channel_client.c
@@ -14,11 +14,15 @@ int main() {
   unsigned short port = 8902; // NOLINT
 
   // message for server
-  TaggedMessage port_message;
-  port_message.conn_id = 42; // NOLINT
+  FederateMessage msg;
+  msg.type = MessageType_TAGGED_MESSAGE;
+  msg.which_message = FederateMessage_tagged_message_tag;
+
+  TaggedMessage *port_message = &msg.message.tagged_message;
+  port_message->conn_id = 42; // NOLINT
   const char *message = "Hello World1234";
-  memcpy(port_message.payload.bytes, message, sizeof("Hello World1234")); // NOLINT
-  port_message.payload.size = sizeof("Hello World1234");
+  memcpy(port_message->payload.bytes, message, sizeof("Hello World1234")); // NOLINT
+  port_message->payload.size = sizeof("Hello World1234");
 
   // creating a server that listens on loopback device on port 8900
   TcpIpChannel_ctor(&channel, host, port, AF_INET);
@@ -28,13 +32,13 @@ int main() {
 
   for (int i = 0; i < NUM_ITER; i++) {
     // sending message
-    channel.super.send(&channel.super, &port_message);
-
+    channel.super.send(&channel.super, &msg);
     // waiting for reply
-    TaggedMessage *received_message = channel.super.receive(&channel.super);
+    const FederateMessage *received_message = channel.super.receive(&channel.super);
+    const TaggedMessage *received_tagged_message = &received_message->message.tagged_message;
 
-    printf("Received message with connection number %i and content %s\n", received_message->conn_id,
-           (char *)received_message->payload.bytes);
+    printf("Received message with connection number %i and content %s\n", received_tagged_message->conn_id,
+           (char *)received_tagged_message->payload.bytes);
   }
 
   channel.super.close(&channel.super);
diff --git a/examples/posix/testing_posix_tcp_ip_channel_server.c b/examples/posix/testing_posix_tcp_ip_channel_server.c
index 68bee971..5d5cbcf7 100644
--- a/examples/posix/testing_posix_tcp_ip_channel_server.c
+++ b/examples/posix/testing_posix_tcp_ip_channel_server.c
@@ -25,9 +25,10 @@ int main() {
 
   for (int i = 0; i < NUM_ITER; i++) {
     // waiting for messages from client
-    TaggedMessage *message = channel.super.receive(&channel.super);
-    printf("Received message with connection number %i and content %s\n", message->conn_id,
-           (char *)message->payload.bytes);
+    const FederateMessage *message = channel.super.receive(&channel.super);
+    const TaggedMessage *tagged_message = &message->message.tagged_message;
+    printf("Received message with connection number %i and content %s\n", tagged_message->conn_id,
+           (char *)tagged_message->payload.bytes);
 
     channel.super.send(&channel.super, message);
   }
diff --git a/examples/posix/testing_tcp_ip_channel_server_callback.c b/examples/posix/testing_tcp_ip_channel_server_callback.c
index c6a4e50c..b5651f85 100644
--- a/examples/posix/testing_tcp_ip_channel_server_callback.c
+++ b/examples/posix/testing_tcp_ip_channel_server_callback.c
@@ -5,9 +5,10 @@
 #include <unistd.h>
 TcpIpChannel channel;
 
-void callback_handler(FederatedConnectionBundle *self, TaggedMessage *msg) {
+void callback_handler(FederatedConnectionBundle *self, const FederateMessage *_msg) {
+  const TaggedMessage *msg = &_msg->message.tagged_message;
   printf("Received message with connection number %i and content %s\n", msg->conn_id, (char *)msg->payload.bytes);
-  channel.super.send(&channel.super, msg);
+  channel.super.send(&channel.super, _msg);
 }
 
 int main() {