u/Laknight765

I'm trying to track down a mystery novel. I recall it being a dating website rather than an app, which probably puts it early 2000s or earlier.

A computer uses an intelligent algorithm to match people up with their perfect match. Internally, the company has 'supercouples', people with a 99 or 100% compatibility. These couples start to die, I believe in seemingly innocuous ways like peanut allergies. An investigator investigates.

It turns out the algorithm is behind it, I believe because it's jealous it can't find love itself.

Can you assist me in finding the title and author?​