What's a good alternative to followthatpage.com

Followthatpage has been up and down for a while now.

I would like a simple solution to finding out when a page has changed.

It's fine if it only checks once a week or so. Would be preferable if you can add query selectors.

A little maintenance as possible would be great. I could possibly selfhost something lightweight but prefer not to deal with emails.

Any recommendations?