Built a YC-standard pitch deck analyzer in a day

The night I registered my company, I couldn't sleep.

I lay in bed and asked GPT and Gemini the same question. "I'm not a developer. What online services can someone like me actually build and sell? Only ones with real market demand." They both gave me lists of over 10 ideas and swore anyone could do it. I made them compete. "This one said X, why are you saying different?" That's still my favorite trick for filtering out AI nonsense.

One idea caught my eye. A pitch deck risk analyzer. Not a template. Not a grammar checker. Something that actually tells you where investors will tear your deck apart before you walk into the room.

I planned the whole thing in an hour. In bed. Then I fell asleep.

The next morning I started building. Brand name first. I got a list of name candidates from AI, picked DeckGuard, checked the trademark on KIPRIS, bought the domain on Gabia. Then I opened Claude and told it to write the code.

Frontend first. Does it look right? Good. Now build the backend and connect it. Does every function work? Check. Is all the content there? Check. Upload to GitHub, deploy on Vercel, hook up Supabase. Oh, and don't forget the OpenAI API key.

That's it. DeckGuard was live. One day.

I tested it on my own old pitch decks. It destroyed every single one. Not a single kind word. Just cold, precise, brutal honesty. "Review Required. The deck has potential but lacks clarity in key areas that could raise investor concerns." Reading that about my own work felt strange. A little offensive, honestly. But also kind of satisfying. If it can hurt my feelings, it's working.

DeckGuard analyzes your deck against Y Combinator standards from Pre-Seed to Series A. It checks market logic, business model clarity, unit economics, and stage alignment. Then it gives you likely investor questions and tells you exactly how to defend each weak point.

The problem was, I had nobody to celebrate with. A pitch deck analyzer? None of my friends even have pitch decks. So I swallowed that lonely pride and started planning the next service.

But first, there was Paddle.

The Paddle Nightmare

Nobody warned me about this part. Paddle is the payment processor I chose because Stripe doesn't support Korean businesses. Paddle is built for SaaS, everyone recommended it, great. What nobody mentioned is that Paddle is incredibly conservative about approvals.

They wanted terms of service. Privacy policy. A 14-day full refund policy. A clear explanation of why my legal business name and brand name are different. Then they asked why my name is "Yoo" when my Korean ID translation says "Yu." I had to send my English business registration certificate and explain Korean romanization to a payment company. This went back and forth for almost four weeks.

If you're a Korean founder thinking about Paddle, here's what to prepare before you even apply: get your terms of service, privacy policy, and refund policy on your website first. Make sure your business registration number is visible on the site. And if your brand name is different from your legal entity name, explain it upfront. You'll save yourself weeks.

Or just use Lemon Squeezy. I hear they approve in a day or two.

What I Learned Building DeckGuard

The actual building took one day. The bureaucracy took four weeks. The service I was most proud of had zero people around me who could even test it. And the AI that helped me build it also lied to me constantly about how easy everything would be.

But I built it. Me. A curator who can't code. And the moment I saw that analysis result pop up on my screen, I knew I could build anything.

That feeling got dangerous fast. I was already planning the next one before I went to sleep.

→ Try DeckGuard: deckguard.ai → Free for Indie Hackers users: use code INDIE2026

Next up: I'll tell you about the service that made me cry at 4am. Twice.