Slide contents

1. 1. Harness engineering: agent environments

   Five months in which Codex wrote all of a product’s code while people built its environment

2. 2. Five months without hand-written code

3. 3. Humans steer; agents write everything

4. 4. Agent failures signal a missing capability

5. 5. Human QA became the bottleneck

6. 6. Every change boots its own app

7. 7. Codex queries logs, metrics and traces

8. 8. What Codex can’t see doesn’t exist

9. 9. AGENTS.md is a table of contents

10. 10. Repo knowledge is versioned and machine-checked

11. 11. Domain layers are enforced mechanically

12. 12. Lint errors tell the agent the fix

13. 13. Enforce invariants, not implementations

14. 14. One prompt: from bug to merge

15. 15. At high throughput, fixing beats waiting

16. 16. Pay down debt daily, not on Fridays

17. 17. The numbers show scale, not cause

18. 18. Five months observed; years remain open

19. 19. Measure each environment capability you add

20. 20. Count accepted tasks and human time

21. 21. Discipline moves from code to scaffolding