Perfectly true, gevent + pypy requires a separate build of gevent, but pypy comes with eventlet, so it might have warranted an investigation to see if it makes sense to switch.

However, I suppose without details of the service itself, it's hard to make a judgment call from the sidelines.

Still, glad you were able to improve performance. Why was 'Go' chosen?

Nevermind, I see that was answered in another thread.