Ask HN: What do you use for user management/IAM in your SaaS app?

Hi! I'm biased as one of the Stytch founders but wanted to share my POV in case it's helpful. As others mentioned, any of the open source options are not going to be low management overhead, but can be great in terms of cost and flexibility. I worked with Keycloak in a previous role and I think it's a really great option if you do go the open source route, just be prepared to spend time managing it.

> True multitenancy Many of the paid options you mentioned (workos, clerk, etc same goes for auth0) aren't actually multitenant, they've tacked on a concept of organizations to a user first data model. This presents some limitations as a result of users as the first class entity versus organizations, for example, membership across multiple organizations with different auth requirements (ie I can log into my personal with sign in with email/google but to log into a company account I need 2fa or SSO), multiple SSO connections per organization or a single SSO connection across multiple organizations (both common in enterprises where there's lots of M&A).

Happy to go into more detail on any of this or answer any specific questions you have!

Feels like you might be overthinking this. Most of the tools you listed already cover 90% of what you’re asking for. If you’re starting a SaaS from scratch and haven’t got a single user yet, sinking too much time into picking the “perfect” auth solution will slow you down more than making a “wrong” choice ever will. The bigger risk is not shipping at all.

I’ve worked with Supabase, Clerk, Keycloak, and Kratos on different projects. None of the open-source options truly deliver on “low management overhead”. You’ll always have to deal with updates, patches, and some manual babysitting.

If you refuse to compromise on your feature list, your realistic options shrink fast. In that case, Zitadel is a solid choice, but be ready for higher costs from day one. My advice is to trim the must-have list, go with a managed service, get real users, and revisit the decision when scale actually becomes a problem.