​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 scratch

• ​Extend an existing open-source project

• ​Prototype 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