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, the standard library is there to help. But what if there’s some Python code you would like to keep or worse, some you can’t get rid of? When we chose to port the Datadog Agent to Go, we had a requirement to maintain our plugin system in Python. During the talk we will share stories about cgo, the GIL and the quest for performance as we bridge multiple languages in a single application.