This is seriously awesome!! I was just chatting with a co-worker today on PhantomCSS and how I felt visual diffing could possibly be replaced with diffing the actual dom tree. Does anyone know of an open source project working on this? If not, I'd love to start one (although I'm sure it would be incredibly difficult)

Too bad they didn't open source this implementation, but they did link a bunch of papers that inspired it.

We will probably open source it in the future. It's a bit hacked together right now, and it depends on code running in different places so it's not easy to deploy.

Those problems are surmountable though, so it's something we'll look at in the coming months.

I'm not sure I understand the pricing plan - limiting on pages tested seems like a bad way to get customers. I would plan on testing quite a few pages per site and testing those after each commit.