Ask HN: What do you about graduates from the University of Waterloo?

You say that you're about to hire one. That sounds like you're fairly certain about this person's skills. But, you're ambivalent, hence the post.

Are you looking for an excuse not to hire someone or for reassurance to do so?

Waterloo is a good school. But, like all good schools, it has a bell curve. Waterloo will produce amazing developers and also abysmal ones. If this person passed your process, he/she is probably good to go.