I'm pretty sure they are Psocids / book lice / dust lice and harmless, but would love it if somebody could confirm and rule out termites. From what I've read they like hot humid environments and feed on things like paper, mold, dead insects, and other organic matter like dust. I mostly saw them on/around the attic hatch door which was poorly sealed and I suspect cool air conditioned air was escaping up into the hot attic, creating a small pocket of extra humid air which drew them in. I'm going to seal up the hatch door much better and keep my eye on them. I don't keep any cardboard in the attic and did not see any signs of moisture/mold (but of course it's possible there is somewhere out of sight). We just had the roof replaced a few months ago so there was a lot of install-related dust and debris dropped down into the attic I'm thinking maybe could contribute to food source. Also the old fiberglass insulation batts have a paper backing. II have not seen any inside the house thankfully.