Events sent over an sse stream should be in order. It’s a single tcp stream with messages separated by newlines. If you’re seeing messages arrive out of order,

Events sent over an sse stream should be in order. It’s a single tcp stream with messages separated by newlines. If you’re seeing messages arrive out of order, there may be a bug in whatever sse stream library you’re using. Http messages of course have no ordering guarantee. If you want ordering (and connection state), websockets might be a better choice.