Streaming Koa server-sent events on Bun: the four things that broke, and what Flight 3.0.1 changed

Bytewells by ThoughtPivot Flight is ThoughtPivot's open-source web framework. Since 3.0.0 it ships flight-bun, a server that runs on Bun.serve and mounts existing Koa backends (export default router.routes()) through a Koa-compat layer. On Oct 18 we pushed 3.0.1 to main. It fixes one thing that matters a lot if you stream: Koa server-sent events (SSE) on flight-bun were buffered until res.end(). The client connected, the server wrote events, and nothing arrived until the stream closed. The fix