Success stories about rewriting Python applications in Go are not big news anymore. The pros and cons are well known, best practices are in place, and the standard library is there to help. But what if you want to keep some of your Python code? When we chose to port the Datadog Agent to Go, we needed to maintain support for our existing library of plugins written in Python. During the talk we will share lessons learned from our experiences with cgo, the GIL and the quest for performance as we bridge multiple languages in a single application.