You're on that site right now!

I know you were joking, but responding in seriousness - while in general it's worthwhile asking "Quis custodiet ipsos custodes?", in this particular case, I don't see any issue with Down Detector detecting the Down Detector Down Detector. Assuming they are in different availability zones, using different code, with a different deployment cadence, this approach works quite well in practice.

Can down detector not detect whether down detector detector is down or not?

Maybe distributed down detection?

I know there are people here perfectly capable of running with that idea and we might just see a distributed down detector announced on HN :)

See, that's the joke, all of them are on cloudflare/us-west-1 so they all go down together anyway

Time for the META Down Detector - detecting which of the three is down

Or "Quis custodiet ipsos custodes?"

I think the original down detectors do

It's detectors all the way down.

There's always another asking, "Are you down?" It's a bit of a bop.

https://youtu.be/DpMfP6qUSBo