In case anyone is interested, I have written a STOMP client in Go. I have also written a fairly simple STOMP server.
The client has been tested against RabbitMQ. There are a reasonable unit test coverage, but it could do with a bit more I suppose.
In the server implementation, all queues and topics are in-memory, but all queue access goes via a QueueStorage interface. Alternative queue storage mechanisms such as file system or database should be straightforward. Having said that, I have only used the server for testing, and to date in-memory queues have been sufficient.
Cheers -- John