Might I suggest NixOS. Same benefits. Auto-updates are disabled by default. But even if they do happen it's not going to try to mess with currently running proc

Might I suggest NixOS. Same benefits. Auto-updates are disabled by default. But even if they do happen it's not going to try to mess with currently running processes. In fact, the old version will still be installed just no longer to default. You could even run both simultaneously (using two separate config directories otherwise you get warnings). Snap seems like a huge regression in the Linux ecosystem.