Known User Auth/Management Solutions?

Hey I have been working on a side project that will probably use AWS Cognito for the MVP. At my place I work they use Vault. I was curious if anyone knew other potential services like this?

Ideally I want something more minimal that can serve JWT’s and handle storing users creds in a secure way. Perhaps a lib to use on the front end to handle user registration/login.

So a frontend like Goauthentik maybe, or Authelia, … or are you simply looking for a secure backend to mint / sign stuff?

Backend mostly.