[sigfubar]

Start looking for that new job before the previous one has ended. This is just a slightly next-level variation of simple networking, where you don't merely make friends all over the place, but make it clear that you'd take a better offer if one were to come along.

[downerending]

+1 for this. In our industry, finding a job when you're unemployed can be quite difficult. Massively so if you're "old". Networking helps with that--definitely recommended.

Also consider gathering "knowledge" resources from your current job. Silly stuff like your dotfiles, but also things like config files from the hosts, parts lists for physical systems, phone directories, etc.

[fred_is_fred]

It's called "dig your well before you are thirsty".