​Welcome to Vienna’s first Codex Community Hackathon.

​Join us for a day of building with Codex alongside our friends at Sentry.

​Who This Event Is For

​This event is designed for developers who already use AI coding tools regularly and are comfortable shipping production-grade code.

Build something new from scratch or push an existing project further using Codex. Run parallel tasks, experiment with Skills, and use worktrees to operate with greater speed and ambition.

This is a hands-on builder event designed to keep the room high-signal and focused on shipping.

​How It Works

​Build something meaningful with Codex. You might:

• ​Start a new project from scratch

• ​Extend an existing open-source project

• ​Prototype a new developer tool or agent workflow

​Teams may have up to 4 members.
To keep the event focused and collaborative, attendance may be capped.

​Build Directions

​If any of these themes excite you, apply:

🔹Agentic Coding
Build developer tools that maximise leverage from Codex as an AI coding agent.

🔹UX for Agentic Applications
Design AI-native interfaces and workflows for agent-driven software.

🔹Multimodal Intelligence
Create applications that reason across multiple modalities.

🔹Domain Agents
Build vertical agents that operate within real-world constraints.

🔹Building Evals
Develop tools to measure, debug, and systematically improve agent performance.

​Prizes

​🥇1st Place — $15,000 USD in OpenAI API credits
🥈2nd Place — $10,000 USD in OpenAI API credits
🥉3rd Place — $5,000 USD in OpenAI API credits

In addition, all members of the top five teams will receive one year of ChatGPT Pro.

​Event Details

​📅 Saturday, April 18
🕘 9:00 AM – 21:00 PM
📍 Location shared upon registration confirmation

​Registration

​Due to venue capacity, registration is subject to approval.

Please complete the registration form (https://codex-hackathons.com/hackathons/codex-vienna-2026-04-18) carefully. Incomplete or inaccurate submissions may not be admitted.

If participating as a team, each member must register individually and receive approval.

​Community Note

​This event is organized by Alex Gavrilescu in his capacity as OpenAI Codex Ambassador.

​Partners / Co-Hosts

​Sentry

​Build with AI, fix with Sentry.
Sentry helps developers detect, understand, and fix broken code fast, so they can get back to building. Used by 4M+ developers and 150K+ organizations including Vercel, Disney+, and GitHub.
Every participant receives $270 in Sentry credits, courtesy of our sponsor Sentry.