It needs to have the .coffee extension (or two variants): https://github.com/github/linguist/blob/master/lib/linguist/languages.yml#L232 https://github.com/gith

It needs to have the .coffee extension (or two variants): https://github.com/github/linguist/blob/master/lib/linguist/languages.yml#L232 https://github.com/github/linguist/blob/master/lib/linguist/...