What should I use instead of building OAuth from scratch?

Instead of building OAuth from scratch, use an established identity/auth provider or OAuth/OIDC library depending on what you need.

Best options

1) Managed identity providers

Good if you want the fastest, safest path.

• Auth0
• Okta
• Firebase Authentication
• AWS Cognito
• Clerk
• WorkOS (great for enterprise SSO)
• Supabase Auth (nice if you’re already using Supabase)

These handle:

• OAuth/OIDC login flows
• token issuance and refresh
• user management
• social logins
• SSO / enterprise connections
• security updates and edge cases

2) Open-source auth platforms

Good if you want more control or self-hosting.

• Keycloak
• ORY (Hydra/Kratos)
• Zitadel
• Dex (more for identity federation)

3) Libraries for implementing OAuth/OIDC clients or servers

Good if you only need protocol support in your app.

• AppAuth (mobile)
• passport.js (Node.js)
• oauthlib (Python)
• Spring Security OAuth2 / built-in Spring Security support
• openid-client (Node.js)
• Authlib (Python)

Important note

If by “OAuth” you mean “login with Google/GitHub/etc.”, you usually want OpenID Connect (OIDC) on top of OAuth 2.0, not raw OAuth alone.

Simple recommendation

• Startup / web app: Auth0, Clerk, Supabase Auth, Firebase Auth
• Enterprise SSO: WorkOS, Okta, Azure AD, Auth0
• Self-hosted: Keycloak or ORY
• Custom app integration: use an OAuth/OIDC library, not a hand-rolled implementation

If you tell me your stack (frontend/backend/cloud) and whether you need social login, SSO, or API access, I can recommend the best specific choice.