In Buffalo v0.9.4 the built in generator for github.com/markbates/goth was removed in favor of this plugin.
$ buffalo plugins install github.com/gobuffalo/buffalo-gothGenerate Users, Routes
$ buffalo generate goth-auth facebook twitter linkedin etc...Generate Routes only
$ buffalo generate goth facebook twitter linkedin etc...For more detailed usage visit https://gobuffalo.io/docs/generators#goth.