Auth & Payments
Authentication, authorization, billing, payment processing, and security.
10 topics
What this section covers
Most AI projects die somewhere between "it works on my machine" and "someone paid me for it." This section is the reference for the two features that close that gap: knowing who the user is, and taking their money without losing their trust. You'll find focused pages on Stripe (including the customer portal integration) and Polar for subscription billing, Clerk for managed auth and billing in one, Supabase Auth for the self-hosted-friendly path, and Login with Google for the single most-requested social provider. Deeper pages on authentication, authorization, and general application security cover the patterns you need when rolling your own — or reviewing something an AI built for you and flagged as "probably fine." It's aimed at developers who are about to put a paywall on their AI-powered product and do not want to explain a data leak to their first ten customers.
Authentication
Authentication is the process of verifying a user's identity, ensuring they are who they claim to be. In web applications, authentication systems manage user...
Clerk Billing for B2C SaaS - Vibe Code Tool Implementation Guide
> **Warning**: This feature is currently in Beta. The low-level JavaScript APIs exposed via `Clerk.billing` are experimental and may undergo breaking changes...
Payment Integration
Payment integration refers to the process of connecting your application with payment processing services to enable financial transactions such as subscripti...
Polar
Polar is a monetization platform built for developers and open-source maintainers. It provides tools for accepting payments, managing subscriptions, and sell...
Security
Web application security is the practice of protecting websites and online services from various security threats and vulnerabilities. Effective security mea...
Setting Up Google Authentication with Supabase in Next.js
Offical documentation: https://supabase.com/docs/guides/auth/social-login/auth-google
Stripe Customer Portal
Add a Stripe Customer Portal so users can manage subscriptions and billing themselves. Covers configuration, session creation, and redirect handling.
Stripe Integration Guide for Next.js/Supabase Applications
Integrate Stripe subscriptions into your Next.js and Supabase app. Covers products, prices, webhooks, billing portal, and checkout session setup.
Stripe Usage-Based Billing
Implement usage-based (metered) billing with Stripe. Meters, meter events, pricing models, proration, and common pitfalls for SaaS and AI products.
Supabase Auth
Supabase Auth is a complete authentication system built on top of Postgres — it stores users directly in your database, integrates natively with Row Level Se...