Harness engineering: leveraging Codex in an agent-first world

What we don’t yet know is how architectural coherence evolves over years in a fully agent-generated system. We’re still learning where human judgment adds the most leverage and how to encode that judgment so it compounds. We also don’t know how this system will evolve as models continue to become more capable over time.

What’s become clear: building software still demands discipline, but the discipline shows up more in the scaffolding rather than the code. The tooling, abstractions, and feedback loops that keep the codebase coherent are increasingly important.

Our most difficult challenges now center on designing environments, feedback loops, and control systems that help agents accomplish our goal: build and maintain complex, reliable software at scale.

There's this very vocal camp of engineers on the internet who like to say things like "it was never about how fast I can type code" and share visceral takedowns of how sloppy and terrible vibecoding and agentic engineering codebases become over time.

I agree with their observations: over time, every vibecoded piece of software I've built becomes shelfware, artifacts of code which served a purpose but is no longer needed.

But I've been programming computers long enough to know that concerns about architecture and sane codebases end up bugging people so much that they invent new techniques to address them.

I am approaching agentic engineering just like I approached using a chainsaw for the second time in my life a couple weeks ago: by consuming a lot of videos and blog posts on how other people are doing it, and then running controlled experiments to see what works for me.