What happens when AI becomes a true coding collaborator? OpenAI co-founder Greg Brockman and Codex engineering lead Thibault Sottiaux talk about the evolution of Codex—from the first glimpses of AI writing code, to today’s GPT-5 Codex agents that can work for hours on complex refactorings. They discuss building “harnesses,” the rise of agentic coding, code review breakthroughs, and how AI may transform software development in the years ahead.
Chapters
1:15 – The first sparks of AI coding with GPT-3
4:00 – Why coding became OpenAI’s deepest focus area
7:20 – What a “harness” is and why it matters for agents
11:45 – Lessons from GitHub Copilot and latency tradeoffs
16:10 – Experimenting with terminals, IDEs, and async agents
22:00 – Internal tools like 10x and Codex code review
27:45 – Why GPT-5 Codex can run for hours on complex tasks
33:15 – The rise of refactoring and enterprise use cases
38:50 – The future of agentic software engineers
45:00 – Safety, oversight, and aligning agents with human intent
51:30 – What coding (and compute) may look like in 2030
57:40 – Advice: why it’s still a great time to learn to code
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