As far as I have seen, so far in my career, this is all 'not invented here' stuff. Most things, like auth go from 'oh no mate, we need 10000x more complicated s

As far as I have seen, so far in my career, this is all 'not invented here' stuff. Most things, like auth go from 'oh no mate, we need 10000x more complicated stuff, that Keycloak thing will never fit!' and then, 6 months later there is something like keycloak but worse, far less features, more complex but replacable in no time by keycloak without touching the keycloak (no customizing) sourcecode. But we cannot because we now invested 6000 hours into it. So now it is ours and we will continue to say it is very complicated and so nothing fits our complicated use case. Alternatively, tell me your complicated auth flows that will not have users running away screaming and are, therefor, bad ideas and should be replaced by cookie cutter stuff. Because that is where all of these things end up.