Next.js 15 AI SaaS Boilerplate — Production-Ready Starter Kit

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Use code **`LAUNCH50`** at checkout before the price doubles. Once the first 20 spots are claimed, the discount expires permanently!

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# Stop Rebuilding Auth, Billing & Credits. Launch Your AI Micro-SaaS This Weekend. ⚡

### The production-ready Next.js 15, Supabase & Lemon Squeezy boilerplate engineered with rock-solid security, atomic credit metering, and zero fluff.

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### The Problem With 90% of SaaS Starter Kits

Most boilerplate templates look great in screenshots, but fail the moment real users hit production:

- **They check credits in JavaScript:** Users open 5 browser tabs or run automated scripts to spend credits they never paid for.

- **Unprotected webhooks:** Forged billing payloads trick your API into unlocking premium tiers.

- **Outdated codebases:** Broken auth setups using deprecated Supabase helpers and messy Next.js Pages router patterns.

**You end up spending 3–4 weeks fixing infrastructure instead of shipping features and making sales.**

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### Enter the Zero-Trust AI Micro-SaaS Engine 🛡️

This boilerplate isn't just UI components glued together—it is an **enterprise-grade, production-audited foundation** designed to protect your bottom line from day one.

#### 🔒 1. Zero-Exploit Credit Metering (PostgreSQL Row Locks)

No client-side hacks. Credit deductions run through a transactional PostgreSQL function using `SELECT FOR UPDATE`. Even if a user spams your endpoint with concurrent requests, your database enforces atomic consistency. Negative balances are mathematically impossible.

#### 💳 2. Cryptographic Lemon Squeezy Integration

Handles both recurring subscriptions (monthly/annual) and one-time credit top-up packs out of the box. 

- Webhooks verified via **HMAC SHA-256** constant-time cryptographic checks (`timingSafeEqual`) to block side-channel attacks.

- Built-in **idempotency registry** prevents double-crediting when payment gateways retry events.

#### 🤖 3. Multi-Model AI Gateway (`/api/generate`)

Engineered to work with Gemini 1.5 Pro, GPT-4o, Claude, or any custom LLM.

- Tracks token consumption, logs execution latency, and records generation history.

- Includes a **Zero-Cost Simulation Fallback** so you can develop and test the entire user journey without burning your own API credits.

#### 🔑 4. Official Next.js 15 App Router & Supabase SSR

Built with the modern `@supabase/ssr` package. HttpOnly secure cookies, Edge middleware route protection, and 100% strict Row-Level Security (RLS) ensuring total data isolation between tenants.

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### 📦 What You Get Inside:

- **Complete Next.js 15 Codebase:** Full source code with TypeScript, Tailwind CSS, App Router, and Edge middleware.

- **Plug-and-Play Database Architecture:** Complete `schema.sql` that provisions tables, triggers, user defaults, and security functions in one click.

- **Conversion-Optimized UI:** Responsive marketing landing page, authentication flow, and modern user dashboard with real-time credit displays.

- **Production Architecture & Setup Guide (PDF):** Step-by-step checklist to deploy on Vercel and configure your database & billing in under 15 minutes.

- **Commercial License:** Build and monetize unlimited personal SaaS apps or client projects.

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### 🚀 The Stack:

- **Core:** Next.js 15 (App Router + Server Components)

- **Database & Auth:** PostgreSQL 15+, Supabase SSR (Strict RLS)

- **Billing:** Lemon Squeezy (Recurring + Top-ups)

- **Styling:** Tailwind CSS

- **Deployment:** 1-Click Vercel Ready

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### 💡 Frequently Asked Questions

**How long does setup take?**

Under 15 minutes. Run the SQL script in Supabase, add your environment variables in Vercel, link your Lemon Squeezy webhook, and your app is live.

**Do I need an active OpenAI or Gemini key to test it?**

No. The built-in developer simulation engine mimics real AI completions locally so you can build out your application logic for free.

**Can I use this for client or commercial work?**

Yes. You receive full commercial rights to build, launch, and monetize commercial SaaS applications.

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### 👉 Grab your early-bird copy now with 50% OFF, plug in your prompt or fine-tuned model, and launch your SaaS before the week is over!