Pardon my ignorance, but how does lox relate to Pisces? I don't get the connection with cancer either, but the first thing that comes to mind on hearing Lox is liquid oxygen as it is used in rockets. So it's a connection between Rust language and astrodynamics. Is there something that makes Pisces more appropriate for this?

Sibling comment mentioned the connection between lox and Pisces, but the connection to Cancer is that the mascot for Rust is a crab.

I assume they’re making a reference to Lox the food (brined Salmon), so a fish is appropriate.