I won Claude Code Build Day with a Colombian Sign Language game. Here's what I built in one hour.

On October 5, 2026, I went to my first Claude Code Build Day, hosted at Universidad Santo Tomás in Bogotá. First event of its kind for me. I walked out with first place.

The project is called Aporta una seña (“contribute a sign”): a game for learning Colombian Sign Language (LSC) with your computer’s camera, where people who know the language can teach new words.

Here’s how I built it, what I changed that very morning, and what I took away. One caveat up front: it’s a prototype, and the signs haven’t been validated by the Deaf community yet.

Why sign language

I had more “useful” ideas for my business, like taking restaurant orders through WhatsApp voice notes. But events like this reward what moves people and can be tried live. And there’s very little out there for Colombian Sign Language.

What drives me is communication. Seeing and understanding people who are invisible to many of us.

What existed before the event

Honesty first: I didn’t build all of it in one hour.

In the days before, I’d built a base game with Claude Code and several agents:

• The camera reads your hand as 21 points, using MediaPipe in the browser. Video never leaves your device.
• Base signs come from LSC70, an open dataset from Universidad del Cauca with 70 signers. I calibrated the alphabet on 11,230 detected hands.
• Alphabet, greetings, your name and numbers.
• A diverse cast of AI-generated teachers, chosen on purpose so anyone could see themselves in the game.

I made mistakes worth sharing. The illustration for the letter P was actually a rotated K. I caught it, we checked it against 50 of 69 LSC70 signers and an academic paper, and redid it.

I also had to choose between an easy game and a correct one. With strict rules, fewer people pass some lessons on the first try. I chose strict. People should learn the signs right.

The pivot that morning

My plan was an “AI tutor”: Claude watches your hand and corrects you.

That morning I changed course after asking two questions:

1. Who should be teaching the signs?
2. How does this grow without me coding every word?

The answer wasn’t AI as the teacher. It was AI making it easy for the people who actually know the language to teach.

What I shipped in the hour

The event ran three hours, with one hour to build. In that hour, with Claude Code and a team of agents working in parallel on the base game, I built the contribution flow:

• Someone who knows LSC records a word three times.
• Only hand landmarks are stored. Never video.
• Claude tidies up the contributor’s explanation into a short description. It doesn’t invent or correct the sign. The contributor is in charge.
• The word is playable immediately, labeled “pending validation”.
• It only goes public once two Deaf signers or interpreters validate it.

With five minutes left, another attendee recorded PLEASE. It worked live in front of the judges. That one sign proved the idea.

How I pitched it

I opened in silence and signed HELLO, looking at a few people in the room.

“I just said hello. Who understood me?”

Almost no hands went up. That silence is everyday life for many Deaf people in Colombia.

Then the demo, and I closed with what’s missing: “We bring the technology. The Deaf community brings the language.”

The rules I set for myself

Same as my client work, clear rules:

• Say “learn”, never “translate”. The game doesn’t translate sign language.
• Say “based on LSC70”, not “teaches the full language”.
• Always say “pending validation”. I’m not Deaf, and I’m not an interpreter.
• Privacy first. Landmarks only, never video, and contributors can withdraw their signs.

How to build something like this fast

If you’re heading to a Build Day or hackathon, here’s what worked:

1. Arrive with a base. Use event time for the new idea, not scaffolding. Be clear about what you built before and what you built there.
2. Pick something that moves people and can be tried live. A demo judges can touch beats any slide.
3. Split the work across agents. One per piece, in parallel. You review and integrate.
4. Have a plan B. A short demo video in case the camera fails.
5. Name what’s missing. Turn your weak spot into your ask.

What I learned

That morning I thought AI should be the teacher. Now I think its best job is to help the people who know teach.

The same holds for business. A good AI system doesn’t replace your team. It lets your team do what they already do well, better.

And one more thing: I came to that event from a sales career, learning to build as I go. If you’re starting out, pick a problem you care about and start today.

Do you know a sign language?

I’m looking for Deaf signers and LSC interpreters to review and contribute signs, and for introductions to INSOR or Fenascol in Colombia. Reach me on LinkedIn.

Thanks to Universidad Santo Tomás, Claude Community Bogotá and the Claude ambassadors for opening the doors.