The product needs it now
- 01Users need personal accounts or profiles
- 02You need to store user-specific data
- 03Access control is required
- 04Personalization features are planned
Core capability
User Authentication
Secure login and registration systems including email/password, social auth, and passwordless options.
2-5 daysTypical timeline
$500 - $2,000Typical range
4Approaches compared
SCOPE DECISION
Does this belong
in the first release?
A capability is only essential when the product promise depends on it. Use these signals to keep the decision tied to user value.
The release works without it
- 01Public-only content with no user data
- 02Simple landing pages or brochure sites
- 03Anonymous-first products (add later)
IMPLEMENTATION OPTIONS
Choose the approach
that fits the product.
The right technology depends on ownership, scale, integration depth, and how much operational responsibility the team wants to carry.
Supabase AuthOpen-source Firebase alternative with PostgreSQL backend
Strengths
- Free tier available
- Built-in row-level security
- Social auth included
- Self-hostable
- Smaller ecosystem than Firebase
- Less documentation
Firebase AuthGoogle backed authentication service
Strengths
- Massive scale
- Excellent documentation
- Many auth providers
- Free tier
- Vendor lock-in
- NoSQL only
- Google dependency
Auth0Enterprise-grade authentication platform
Strengths
- Highly customizable
- Enterprise features
- Compliance certifications
- Expensive at scale
- Complex for simple needs
NextAuth.jsOpen-source auth for Next.js applications
Strengths
- Free
- Highly flexible
- Database agnostic
- Great Next.js integration
- Requires more setup
- Self-managed security
DELIVERY SEQUENCE
A practical path
through the work.
- 01Choose authentication provider based on requirements
- 02Set up user database schema
- 03Implement registration flow with email verification
- 04Add login with session management
- 05Configure password reset flow
- 06Add social login providers (optional)
- 07Implement protected routes and middleware
- 08Add logout and session cleanup
WATCH FOR
Common implementation mistakes.
- 01Storing passwords in plain text (always hash)
- 02Not implementing email verification
- 03Weak password requirements
- 04Missing rate limiting on auth endpoints
- 05Not handling session expiration properly
- 06Exposing user IDs in URLs
QUESTIONS
Before you commit the scope.
Should I use social login or email/password?+
Start with email/password for ownership of user data, then add social login as a convenience. Social-only auth creates dependency on third parties.
How do I handle password resets securely?+
Use time-limited tokens (1-24 hours), one-time use, and send reset links via email. Never expose whether an email exists in your system.
Is passwordless auth worth it for MVPs?+
Magic links reduce friction but add email deliverability concerns. Consider it for B2B products where users have reliable email access.
RELATED DECISIONS
Continue mapping the release.
DISCUSS YOUR APP
Turn this decision
into working software.
Bring the product context and current scope. We will choose the approach after the release is clear.
Discuss your app