I originates when a link is upvoted.

It's probably a syntax error. I just did this tutorial and it's working. You can check your code against their repo. The link is near the top of the first section where you start installing things.

thanks for chiming in @ehodges 🙂 @Jonathan, if you still have problems, feel free to report an issue here: https://github.com/howtographql/howtographql/