Cyclone is a realtime push messaging library for Go that can be used with Server Sent Events (SSE) to provide asynchronous non-blocking broadcasts of server-sent events over HTTP. Cyclone-SSE is an open source project that combines Cyclone with SSE to provide a polyfill for broadcasting SSE messages using long-polling, HTTP, Redis, or AMQP. It aims to handle DOM exceptions and work around limitations of Nginx. An example shows logging message data received from an EventSource to the browser console.