Anyone using boost on the backend with a 1x setup? What cranks are you using and did you have to do anything to get the chainlink right?

Yeah, I am, but it all came on the bike!
In theory, Boost needs a specific crank with a +3mm chainline. SRAM and Shimano both make them.
It might work without but they are available, so maybe best to go the whole hog

https://www.evanscycles.com/shimano-xt-m8000-single-crankset-without-chainring-EV249119

https://www.sram.com/sram/mountain/products/xx1-x-sync-crankset

If your frame has chainring clearance, then a standard 50mm chainline works better. Not all frame/chainring sizes allow this though.

Running standard RF Next cranks and working fine with XT 11 speed cassette.

I’ve ran a non boost m8000 single ring on my boosted FS and it was fine, got the proper boosted crank now though so that’ll be going on.

I’m running standard XTR M9020 cranks on a Trek Stache and the chainline is better, it doesn’t drop down when back pedalling in the lowest gear, however, as suggested above this might not work if your chainstay is in a normal place.

running standard cranks also. It works

Had non boost on my boost bike for a couple of rides waiting for my specific hope ones, it worked fine