Every software engineer should be paying attention to Boris Cherny's Steps of AI Adoption.

The products and tools are obviously Anthropic Claude/Claude Code specific, but it should transfer generally to the likes of Codex, OpenCode and others as these harnesses continue to rapidly mature.

Level 0 and 1

Level 1 is really the entry point into agentic engineering. I'm surprised by the number of engineers I talk to that are still at level here. Things are moving too fast to be complacent at these levels.

The bottleneck things of level 0, in my opinion, apply at all the levels.

Level 2

Most software engineers are, or should at least be, operating at this level.

Level 3

This is where I spend most of my time. It's incredibly satisfying when Claude is fully autonomously cooking on something, or a few things. Automated maintenance tasks are something I can lean more into, but for features or larger improvements I just don't have enough work in a fully planned design/spec state to be running many things in parallel. The planning/design phase, knowing exactly what to build, consumes a very large portion of my time. The good news is this can be done while Claude is cooking on something else.

Below is an example of a recent feature build I ran using a dynamic workflow script that I have been refining. It's slow and meticulous, taking 13 hours to complete. It handled everything from writing its own implementation plan for a design I gave it, all the way through implementation and verification loops with unit, component and e2e tests, to creating a draft PR for me to review offering proof of completion and a ledger of work completed and decisions made. It was only 66 agents, but the nature of this particular piece of work meant not that many things could run in parallel without the agents stepping on each other's toes. Side note, Opus 5 on this workflow run smashed this piece of work out of the park. 73 files +3431 -1147 lines of code. After self-reviewing and self-testing, not a single thing needed changing; this was a straight 100% complete ready-to-merge change. Fable and Opus 5 are just incredible!

Level 4

To be honest, I was a bit surprised to see here that Claude Code isn't even used at this level, but instead building custom mini-harnesses with the Agent SDK. I can see how this works; it's basically the output of Claude Code creating a dynamic workflow, which is just a script built with the Agent SDK. I haven't tried running these without Claude Code yet, but it would appear these dynamic workflow scripts can be used in just this way.

Getting to this level must mean knowing exactly what the agents should be building. Who is planning this work and getting it into a ready state for the agents to just jump in and start building? Surely it can't be just one person — yet Boris Cherny says he is now operating at level 4. My guess here is that it's larger, more ambitious pieces of work that can run for days or even weeks at a time, provided the goal is clear to the agent and a harness exists to keep them on track on their mission.