OpenAI Build Week Community Hackathon - London

Welcome to London’s Codex Community Hackathon. Join us for a day of building with Codex, OpenAI's Coding Agent. This is a hands-on builder event designed to keep the room high-signal and focused on shipping. 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. How it works 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. Build something meaningful with Codex. You might: Start a new project from scratchExtend an existing open-source projectPrototype a new developer tool or agent workflow Prizes 🥇 1st Place — $5,000 USD in OpenAI API credits🥈 2nd Place — $2,000 USD in OpenAI API credits🥉 3rd Place — $1,000 USD in OpenAI API credits In addition, all members of the top five teams will receive one year of ChatGPT Pro. Event details 📅 Saturday 18th July 2026🕐 10am - 7pm📍 Location shared upon registration confirmation Registration Due to venue capacity, registration is subject to approval. Please complete the registration form carefully. Incomplete or inaccurate submissions may not be admitted. Teams may have up to 4 members. If participating as a team, each member must register individually and receive approval. Community note This event is organised by Andy Tyler in their capacity as Codex Ambassador, with support from the AI Demo Night Crew