I am currently using Auth0 which has all the cool functionality of logging in with 3rd party services, user management, and so forth. I think I am paying them $25/m to use it, something fairly trivial but non-zero.

If I were getting started with logins again, I'd say I could pay you $250 one time just to download all the code, and roll it out on my own systems in minutes. This way I'd have user auth with easiest setup, and no need to reinvent it on my own. Probably.

But, are you just testing things, or is Login.land real? Since your own login system asks for password, instead of email-based auth like you are showing in the screenshots, I suspect that maybe this is just a test :)