Very interesting. The options it proposed were Keycloak, Dex, and Ory. Has anyone used any of these tools for custom OIDC and can speak to how difficult or easy it was to setup and maintain?

Keycloak comes with the full IAM stack, so if you need that good; if you just need the OAuth server, its a bit much in my opinion. Have not tried Dex so can't speak to that.

https://github.com/ory/hydra https://github.com/keycloak/keycloak