Very interesting talk! I was following along and had an issue reproducing the examples in your talk in my own source files, and now I see that I'm having the same issues in apigen's code.
Specifically, when I go get this repo then add a logging statement and run
$ go generate api/api.go
I see that os.Getenv("GOFILE") == "api.go", not "../api/api.go" . Any idea what I'm doing wrong?