Exploring a new way to build games with Codex
Games have long been a place where new technology changes not only what people create, but how they create it.
OpenAI Game Builders Seoul is OpenAI’s first game hackathon focused on building with Codex. This event brings builders together to turn ideas into playable games, experiment with AI-native development workflows, and explore what changes when Codex becomes part of the creative process.
The goal is not simply to build games faster. It is to see what more people can create when the distance between an idea and something playable gets shorter.
Why Seoul?
Korea has built one of the world’s most influential gaming ecosystems, shaped by generations of developers and players across MMORPGs, live-service games, mobile titles, and beyond. It is also one of the countries with a long-standing tradition of experimenting with how games are built, played, and operated.
New technology becomes meaningful when builders put it to work. Game Builders Seoul brings Codex to a community that has repeatedly pushed games in new directions and gives developers a place to explore where it can take them next.
From idea to game with Codex
Codex is OpenAI’s coding agent, designed to help developers write, modify, and test code using natural-language instructions.
At Game Builders Seoul, participants will use Codex throughout the development process: starting with an idea, building a playable prototype, testing it, and iterating toward a more complete game.
The workflow extends beyond development.
Through the Codex plugin for Hive, Com2uS’s game backend platform, participants can connect their games to capabilities needed for launch and live operations, including authentication, payments, user analytics, and security.
“Build with Codex, Play with Hive.”
From idea to prototype, and from prototype toward a live game, this event is designed to explore a more connected way to build with AI.
Experience the full potential of Codex
🕹️ Game Builders Seoul will explore that workflow through two tracks.
Track 1 : From Zero to One: Build with Codex
Participants can submit their games built with Codex for the online warm-up phase. Based on Track 1 submissions, 40 teams will be shortlisted and invited to the one day hackathon.
Shortlisted teams will deliver an elevator pitch presenting their idea and their journey of using Codex, including their game building process, how their ideas evolved through iteration, and what they learned along the way.
🏆 Prize and Reward
🎁 OpenAI One-Day Hackathon Reward
All shortlisted teams participating in the one-day hackathon will receive $100 in OpenAI API credits.
Track 1 Final Winners
$50,000 in total OpenAI API credits
One-year ChatGPT Pro subscriptions
Track 2 : Go Full Codex: 5 Hour Build
The second track is designed to push Codex to its limits in a short, high-intensity build session.
The shortlisted teams will have five hours to build a game on site, moving from an initial idea to something playable within a limited window.
🏆 Prize and Reward
Track 2 Final Winners
One-year ChatGPT Pro subscriptions
Building the next way to build
Game Builders Seoul is an experiment in what game development can look like when AI becomes part of the workflow from the start.
What happens when builders can test more ideas? When a prototype can become playable sooner? When smaller teams can take on work that previously required more time or resources?
We expect the answers to come from the builders themselves.
By bringing developers together to build, play, and share what they learn, OpenAI Game Builders Seoul is a place to explore the next way games get made.
Build with Codex, Play with Hive.