in the .net world I use IdentitySever 4 and have connected various other things into that environment without too much trouble. But the lingo/jargon of the identity world felt like a bit of a brick wall when trying to work out how things work. There's still a bunch of stuff I really am quite fuzzy on. There's a bit of massaging in the middleware that I need to do to get things to work nicely. But at least having ID4 as a isolation layer helps. Was very tedious.