OpenAI Build Week opened at 10 a.m. PDT today, July 13 (official event page). The global challenge runs through July 21, asks you to build with Codex, and has a $100,000 prize pool (official rules). If you have a project sitting in your backlog that’s Codex-shaped, this is the fastest path to shipping it with upside attached.
This is the entry guide.
What Build Week Is
Build Week is a structured, week-long hackathon organized around OpenAI’s Codex. It’s not a loose prompt competition — you submit a working project, judged on four criteria (below), and there are daily live sessions across the week to support builders.
The event is global. OpenAI has 40+ in-person and virtual community meetups running in parallel with the online challenge, organized by local ambassadors and community groups. Whether you attend one or work solo remotely, the submission funnel runs through Devpost.
Registration and submissions: openai.devpost.com
The Prize Pool
Total: $100,000, split across eight cash awards ($15,000 each for 1st place, $10,000 each for 2nd place) in four categories — Apps for Your Life, Work and Productivity, Developer Tools, and Education (official rules). Prizes and perks include:
- Cash awards (above)
- $100 in free Codex credits for all registered participants (not conditioned on winning)
- DevDay passes for winners (up to 2 per team, ~$650 value each)
- Promotion/spotlight from OpenAI Developers
- A meeting with the Codex team (1st place) and a one-year Pro account
(Full prize breakdown.) The winner announcement is around August 12 — roughly three weeks after submission close (official rules).
Session Schedule
OpenAI is running daily sessions with live participation (schedule). All times PDT:
| Date | Time | Notes |
|---|---|---|
| July 13 (today) | 10:00 a.m. | Opening session — Greg Brockman, Thibault Sottiaux, Corey Ching (source, source) |
| July 14 | 11:00 a.m. | |
| July 15 | 10:00 a.m. | |
| July 16 | 12:00 p.m. | |
| July 17 | 8:30 p.m. | |
| July 20 | 10:00 a.m. | |
| July 20 | 11:00 a.m. | |
| July 21 | 8:30 a.m. | Final day / submission close |
Daily: community office hours on Discord and OpenAI Academy sessions for onboarding.
What to Build
The event centers on Codex, OpenAI’s code generation system. Projects should use Codex meaningfully — not as decoration. OpenAI’s suggestion: “bring the idea sitting in your backlog.”
High-signal project shapes based on judging criteria:
- Automation tools: Codex managing repetitive dev workflows (CI scripting, test generation, PR summarization)
- Developer productivity: Building with GPT-5.6 + Codex for code review, documentation, or refactor suggestions
- Domain-specific code tools: Specialized coding assistants for a narrow vertical (legal contract templating, data pipeline generation, infrastructure-as-code)
- Agent scaffolding: Projects where Codex is the execution layer, not just a suggestion engine
The judges are looking for projects where Codex does meaningful work, not projects that technically invoke the API once.
Judging Criteria
Four dimensions, equally weighted (official rules):
- Technical implementation — Does it actually work? Is the Codex integration substantive?
- Design and UX — Can someone who didn’t build it use it?
- Potential impact — Does it solve something real, at meaningful scale?
- Quality of idea — Is the underlying problem worth solving?
Strong submissions communicate the problem, solution, and approach clearly. The Devpost description matters as much as the demo.
What Codex + GPT-5.6 Gives You
The event is aligned with the broader GPT-5.6 rollout — Sol, Terra, and Luna went generally available July 9. If your project involves:
- Long-horizon agentic code tasks → Sol ($5/M in, $30/M out)
- Production code generation at scale → Terra ($2.50/M in, $15/M out)
- Latency-sensitive routing, extraction → Luna ($1/M in, $6/M out)
(Launch-day pricing per OpenAI, effective July 9; OpenAI cut Terra and Luna pricing later in July.)
Codex itself sits atop this stack and adds the code-specific fine-tuning, context handling, and tool integration.
What This Signals
OpenAI launched Build Week the same week GitHub Models runs its first scheduled brownout (July 16) — part of GitHub’s wind-down toward full retirement on July 30 — and four days after GPT-5.6 went generally available on July 9. The sequencing is deliberate: OpenAI is pulling developers toward its own stack as the free-hosting alternatives disappear.
The Codex focus is also notable. Cursor’s enterprise spend share has slid from 41% in June 2025 to 26% by May 2026, driven largely by competition from Claude Code — a decline that predates but forms the backdrop to SpaceX’s $60B agreement to acquire Cursor’s parent company, Anysphere, announced June 16, 2026. OpenAI has an interest in showing that building with Codex directly, without an IDE intermediary, is viable. Build Week is partly a proof-of-concept campaign.
For builders: the competitive window on this hackathon is real. Seven days is short enough that deep-pocketed teams have limited compounding advantage. A sharp vertical tool with clear demo beats a broad platform with poor communication.
Submission deadline: July 21, 2026. Register at openai.devpost.com.