From prototype to market launch: A checklist for solopreneurs

You built an app with AI. It works. Users can sign up, do the thing, and see results. Congratulations, you are 95% there. This guide covers the final 5% that separates a working prototype from a product people will pay for.

Phase 1: Security Basics

Before anything else, make sure your app is not leaking data or exposing vulnerabilities. These are non-negotiable.

Move all API keys and secrets to environment variables. Check that .env files are in your .gitignore. Search your codebase for any string that looks like a key or token, if you find one hardcoded, move it immediately.

Enable database security. If you use Supabase, turn on Row Level Security for every table with user data. Write policies that restrict access to the data owner. Test this by trying to access another user's records.

Validate all inputs. Every form, every API endpoint, every URL parameter. Use Zod or a similar library. Set maximum lengths. Escape HTML output. Never trust user input.

Add rate limiting to your API routes. Even a simple in-memory rate limiter is better than nothing. It prevents automated abuse of your endpoints.

Phase 2: Payment Integration

If you want to get paid, you need a payment system. Stripe is the standard for most solopreneurs building with AI tools. Here is what to get right.

Use Stripe Checkout or Stripe Elements, never build your own payment form. PCI compliance is not something you want to handle yourself. Let Stripe manage the sensitive card data.

Implement webhook handlers to confirm payments server-side. Do not rely on client-side confirmation alone. A user could bypass the payment step if your app only checks on the frontend.

Test in Stripe's test mode first. Use test card numbers. Verify that subscriptions create, renew, and cancel correctly. Check that failed payments are handled gracefully.

Phase 3: Legal and Compliance

This is the phase most solopreneurs skip entirely. Do not be that person. Legal issues can kill a product faster than any bug.

Create a Privacy Policy. If you collect any personal data (names, emails, usage data), you need one. It must describe what data you collect, why you collect it, how you store it, and how users can request deletion. You can use a generator as a starting point, but review it carefully.

Create Terms of Service. This protects you legally and sets expectations with your users. Cover liability limitations, acceptable use, and your refund policy.

Add cookie consent if you serve EU users. This is not optional under GDPR. Use a consent management tool that blocks analytics cookies until the user accepts.

If you process payments, display your business details. Many countries require a business name, address, and registration number on commercial websites.

Phase 4: Performance and Reliability

Your app needs to be fast and stable. Slow loading times and crashes will kill conversions before your marketing has a chance to work.

Run Google PageSpeed Insights or Lighthouse on your key pages. Target a score above 90 on mobile. Common fixes: optimise images with next/image, use next/font for web fonts, remove unused JavaScript, and enable proper caching headers.

Add error monitoring. Use a service like Sentry or Vercel's built-in error tracking. You need to know when things break in production, not from angry customer emails.

Set up uptime monitoring. Use a free tool like UptimeRobot to ping your site every few minutes. Get alerted when it goes down so you can respond before most users notice.

Phase 5: Launch Readiness

You have secured the app, added payments, handled legal requirements, and ensured performance. Now prepare for launch day.

Set up a custom domain and configure HTTPS. This is standard with most hosting providers like Vercel or Netlify. Make sure www and non-www both work and redirect to a single canonical URL.

Configure email delivery. If your app sends emails (confirmations, notifications, password resets), use a proper email service like Resend, SendGrid, or Postmark. Do not send from your personal Gmail.

Test the complete user journey end-to-end. Sign up as a new user. Complete the core flow. Make a payment. Receive the confirmation. Try to break things. Have a friend try to break things.

Submit your sitemap to Google Search Console. Set up basic analytics. Prepare your launch post for Product Hunt, LinkedIn, or wherever your audience lives.

The 95/5 Rule

Here is the thing about vibe coding: the AI gives you 95% of a product. It is impressive, functional, and fast. But that last 5% (security, compliance, payment integrity, performance) is what separates a prototype from an operating business.

Most solopreneurs skip this phase because it feels tedious compared to the excitement of building. But this is where revenue lives. A secure, compliant, reliable product converts. A prototype with security holes does not.

If this checklist feels overwhelming, we can help. You can always start with a NEKOD free assessment and if needed, scan your code repo. We will identify every gap between your prototype and a launchable product, prioritised by severity and effort to fix.