Identity Providers and Services
Building authentication from scratch is surprisingly complex — password hashing, session management, email verification, password reset flows, multi-factor authentication, and security updates. Identity providers handle this complexity so you can focus on your application.
Dedicated Authentication Providers
Auth0 offers a comprehensive feature set including social logins, enterprise connections, and extensive customization. It's popular for its developer experience and scales from startups to enterprises. The free tier is generous for small projects.
Clerk takes a modern, developer-first approach with pre-built UI components and excellent React integration. It handles user management, organizations, and multi-tenancy out of the box.
Okta (which owns Auth0) focuses on enterprise identity management. If you need SAML, LDAP integration, or complex organizational structures, Okta specializes in these scenarios.
Backend-as-a-Service Authentication
Firebase Auth integrates seamlessly with Google's ecosystem. It's simple to set up, supports multiple providers, and works well for mobile apps. The trade-off is less customization compared to dedicated providers.
Supabase Auth provides open-source authentication built on PostgreSQL. You get row-level security integration and can self-host if needed. It's excellent if you're already using Supabase for your database.
AWS Cognito fits naturally into AWS infrastructure. It handles user pools and identity pools for accessing AWS services. The learning curve is steeper, but it's cost-effective at scale.
Self-Hosted Options
Keycloak is a full-featured, open-source identity server. It supports OAuth, OIDC, SAML, and LDAP. You maintain it yourself, but you have complete control and no per-user costs.
Authelia provides lightweight, self-hosted authentication with multi-factor support. It's simpler than Keycloak and works well as an authentication portal for multiple services.
Choosing a Provider
Consider cost carefully — free tiers have limits, and per-user pricing adds up. Evaluate features needed — do you need enterprise SSO, or just social login? Check ecosystem fit — Firebase Auth makes sense with Firebase, Cognito with AWS. Assess customization needs — some providers limit how much you can modify flows. Review compliance requirements — some industries require specific certifications or data residency.
Start with a managed provider unless you have specific reasons to self-host. The security expertise these services provide is worth the cost for most applications.