I have a demo of this for CF workers https://github.com/hntrl/eventkit/tree/main/examples/workers-chat-demo https://github.com/hntrl/eventkit/tree/main/examples

I have a demo of this for CF workers https://github.com/hntrl/eventkit/tree/main/examples/workers-chat-demo https://github.com/hntrl/eventkit/tree/main/examples/workers... (it's not SSE in particular, but it demonstrates that you can have a long running stream like SSE)