Post a longtime job out of grad school via on-campus interview (which is a bit of an irrelevant story itself), every other of my (few) jobs were through a professional network. Nothing formal, but people I ran into and maintained some connection with. I know there are a lot of people who (at least until recently) are they just ping a recruiter and get offers dropped in their lap. Or who are deeply resentful that it seems like "who you know" is the modus operandi for some. But without being anything like deliberate or cynical about the whole thing, it worked for me.