LaunchFast AI Starter Kit
Ship your AI SaaS in days, not weeks. Auth, protected routes, OpenAI + fal.ai FLUX routes, and Gumroad payment webhook — all wired up and ready to run.
Next.js 16 (App Router) · React 19 · Tailwind CSS 4 · TypeScript · Supabase
Secure checkout via Polar · 30-day money-back guarantee
What you get
Supabase Auth (Server Actions)
Sign-up, sign-in, sign-out built on Supabase with Server Actions. No client-side auth juggling — the session is read server-side from the start.
Middleware-protected dashboard
middleware.ts guards every /dashboard/* route. Unauthenticated requests are redirected before the page even renders.
Ready-made AI API routes
/api/generate wires up OpenAI (text) and fal.ai FLUX (image generation). Both endpoints ship with a working demo so you can see them run immediately.
Gumroad webhook handler
POST /api/webhook/gumroad verifies the sale and grants access to the buyer automatically. Swap in your own product logic without rewriting the plumbing.
Conversion-focused landing page
Hero, Features, Pricing, and Footer sections with SEO meta tags pre-filled. Replace the copy, keep the structure.
Modern stack — zero legacy
Next.js 16 (App Router), React 19, Tailwind CSS 4, TypeScript strict mode. No pages router, no class components, no outdated patterns.
What's inside the ZIP
- +src/app/(auth)/signin/page.tsx — sign-in form, Server Action
- +src/app/(auth)/signup/page.tsx — sign-up form, Server Action
- +src/app/dashboard/page.tsx — protected page (redirects if unauthenticated)
- +src/app/api/generate/route.ts — OpenAI text + fal.ai FLUX image generation
- +src/app/api/webhook/gumroad/route.ts — verified Gumroad sale handler
- +src/app/page.tsx — conversion landing page (Hero/Features/Pricing/Footer)
- +middleware.ts — route protection for /dashboard/*
- +src/lib/supabase/ — server & browser Supabase client helpers
- +.env.example with all required placeholders
- +README.md — 10-minute setup guide (Türkçe)
- +Commercial license (use in unlimited of your own products)
Requirements
- ·Node.js 18 or newer
- ·Free Supabase account (auth + database)
- ·OpenAI API key (optional — only needed for text generation demo)
- ·fal.ai API key (optional — only needed for image generation demo)
Who is it for
- ✓Solo devs who want to skip the auth + AI plumbing and start on the actual product.
- ✓Developers building a paid AI tool and need Gumroad access-gating from day one.
- ✓Anyone who wants a clean Next.js 16 + Supabase baseline without digging through docs for a week.
Honest note
This is a starter kit, not a magic money printer. It removes roughly 40 hours of boilerplate so you can focus on the part only you can build — the actual product. You still need to write the feature that makes your SaaS worth paying for.
Secure checkout via Polar · Instant download · 30-day money-back guarantee
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