Agent Skills: SaaS MVP Launcher

SaaS MVP Launcher

Overview

This skill guides you through building a production-ready SaaS MVP in the shortest time possible. It covers everything from idea validation and tech stack selection to authentication, payments, database design, deployment, and launch — using modern, battle-tested tools.

When to Use This Skill

• Use when starting a new SaaS product from scratch
• Use when you need to choose a tech stack for a web application
• Use when setting up authentication, billing, or database for a SaaS
• Use when you want a structured launch checklist before going live
• Use when designing the architecture of a multi-tenant application
• Use when doing a technical review of an existing early-stage SaaS

Step-by-Step Guide

1. Validate Before You Build

Before writing any code, validate the idea:

Validation checklist:
- [ ] Can you describe the problem in one sentence?
- [ ] Who is the exact customer? (not "everyone")
- [ ] What do they pay for today to solve this?
- [ ] Have you talked to 5+ potential customers?
- [ ] Will they pay $X/month for your solution?

Rule: If you can't get 3 people to pre-pay or sign a letter of intent, don't build yet.

2. Choose Your Tech Stack

Recommended modern SaaS stack (2026):

| Layer | Choice | Why | |-------|--------|-----| | Frontend | Next.js 15 + TypeScript | Full-stack, great DX, Vercel deploy | | Styling | Tailwind CSS + shadcn/ui | Fast, accessible, customizable | | Backend | Next.js API Routes or tRPC | Type-safe, co-located | | Database | PostgreSQL via Supabase | Reliable, scalable, free tier | | ORM | Prisma or Drizzle | Type-safe queries, migrations | | Auth | Clerk or NextAuth.js | Social login, session management | | Payments | Stripe | Industry standard, great docs | | Email | Resend + React Email | Modern, developer-friendly | | Deployment | Vercel (frontend) + Railway (backend) | Zero-config, fast CI/CD | | Monitoring | Sentry + PostHog | Error tracking + analytics |

3. Project Structure

my-saas/
├── app/                    # Next.js App Router
│   ├── (auth)/             # Auth routes (login, signup)
│   ├── (dashboard)/        # Protected app routes
│   ├── (marketing)/        # Public landing pages
│   └── api/                # API routes
├── components/
│   ├── ui/                 # shadcn/ui components
│   └── [feature]/          # Feature-specific components
├── lib/
│   ├── db.ts               # Database client (Prisma/Drizzle)
│   ├── stripe.ts           # Stripe client
│   └── email.ts            # Email client (Resend)
├── prisma/
│   └── schema.prisma       # Database schema
├── .env.local              # Environment variables
└── middleware.ts           # Auth middleware

4. Core Database Schema (Multi-tenant SaaS)

model User {
  id            String    @id @default(cuid())
  email         String    @unique
  name          String?
  createdAt     DateTime  @default(now())
  subscription  Subscription?
  workspaces    WorkspaceMember[]
}

model Workspace {
  id        String    @id @default(cuid())
  name      String
  slug      String    @unique
  plan      Plan      @default(FREE)
  members   WorkspaceMember[]
  createdAt DateTime  @default(now())
}

model Subscription {
  id                 String   @id @default(cuid())
  userId             String   @unique
  user               User     @relation(fields: [userId], references: [id])
  stripeCustomerId   String   @unique
  stripePriceId      String
  stripeSubId        String   @unique
  status             String   # active, canceled, past_due
  currentPeriodEnd   DateTime
}

enum Plan {
  FREE
  PRO
  ENTERPRISE
}

5. Authentication Setup (Clerk)

// middleware.ts
import { clerkMiddleware, createRouteMatcher } from '@clerk/nextjs/server';

const isPublicRoute = createRouteMatcher([
  '/',
  '/pricing',
  '/blog(.*)',
  '/sign-in(.*)',
  '/sign-up(.*)',
  '/api/webhooks(.*)',
]);

export default clerkMiddleware((auth, req) => {
  if (!isPublicRoute(req)) {
    auth().protect();
  }
});

export const config = {
  matcher: ['/((?!.*\\..*|_next).*)', '/', '/(api|trpc)(.*)'],
};

6. Stripe Integration (Subscriptions)

// lib/stripe.ts
import Stripe from 'stripe';
export const stripe = new Stripe(process.env.STRIPE_SECRET_KEY!, {
  apiVersion: '2025-01-27.acacia',
});

// Create checkout session
export async function createCheckoutSession(userId: string, priceId: string) {
  return stripe.checkout.sessions.create({
    mode: 'subscription',
    payment_method_types: ['card'],
    line_items: [{ price: priceId, quantity: 1 }],
    success_url: `${process.env.NEXT_PUBLIC_URL}/dashboard?success=true`,
    cancel_url: `${process.env.NEXT_PUBLIC_URL}/pricing`,
    metadata: { userId },
  });
}

7. Pre-Launch Checklist

Technical:

• [ ] Authentication works (signup, login, logout, password reset)
• [ ] Payments work end-to-end (subscribe, cancel, upgrade)
• [ ] Error monitoring configured (Sentry)
• [ ] Environment variables documented
• [ ] Database backups configured
• [ ] Rate limiting on API routes
• [ ] Input validation with Zod on all forms
• [ ] HTTPS enforced, security headers set

Product:

• [ ] Landing page with clear value proposition
• [ ] Pricing page with 2-3 tiers
• [ ] Onboarding flow (first value in < 5 minutes)
• [ ] Email sequences (welcome, trial ending, payment failed)
• [ ] Terms of Service and Privacy Policy pages
• [ ] Support channel (email / chat)

Marketing:

• [ ] Domain purchased and configured
• [ ] SEO meta tags on all pages
• [ ] Google Analytics or PostHog installed
• [ ] Social media accounts created
• [ ] Product Hunt draft ready

Best Practices

• ✅ Do: Ship a working MVP in 4-6 weeks maximum, then iterate based on feedback
• ✅ Do: Charge from day 1 — free users don't validate product-market fit
• ✅ Do: Build the "happy path" first, handle edge cases later
• ✅ Do: Use feature flags for gradual rollouts (e.g., Vercel Edge Config)
• ✅ Do: Monitor user behavior from launch day — not after problems arise
• ❌ Don't: Build every feature before talking to customers
• ❌ Don't: Optimize for scale before reaching $10k MRR
• ❌ Don't: Build a custom auth system — use Clerk, Auth.js, or Supabase Auth
• ❌ Don't: Skip the onboarding flow — it's where most SaaS lose users

Troubleshooting

Problem: Users sign up but don't activate (don't use core feature) Solution: Reduce steps to first value. Track with PostHog where users drop off in onboarding.

Problem: High churn after trial Solution: Add an exit survey. Most churn is due to lack of perceived value, not price.

Problem: Stripe webhook events not received locally Solution: Use Stripe CLI: stripe listen --forward-to localhost:3000/api/webhooks/stripe

Problem: Database migrations failing in production Solution: Always run prisma migrate deploy (not prisma migrate dev) in production environments.