Spec-Driven Development

Field reports from running a product team where AI agents build from my specs

Spec-driven development (SDD) is the practice of writing a specification so detailed, unambiguous, and complete that an AI coding agent can implement it with zero human clarification. I run a product team built entirely on this idea: I write the specs, agents write the software, and a human still reviews every merge. The essays below are field reports from that work, in reading order, with the caveats left in. The six operating principles underneath the practice are on the expertise page.

Part 1

The Skills You Didn't See Coming

Spec-driven development is a real, teachable skill, and almost nobody starts with all of it. A map of the four skills it rewards, who sits where, and how any role grows into the work.

Work Part 2

One of My Teams Has No Engineers

I manage four product teams. Three are conventional. The fourth has no engineers: I write the specs and artificial intelligence agents build the software, with a human still reviewing every merge. A field report on what spec-driven development actually changes about the product job.

Work Part 3

Evaluation Is the New Code Review

In spec-driven development, writing the spec gets the attention. The skill that actually decides quality is evaluation: designing the tests that prove the output is right, which takes domain truth and failure sense at the same time.

Work Part 4

The Org Chart Lags Reality

With an agent, a lot of a role becomes automatable fast. What holds it up is rarely the technology. It is the organization: the last stretch of a job someone is unwilling to hand over, and a structure built for the old distribution of work.

Work Part 5

This Website Runs Itself

This site publishes a post every Sunday, sends the newsletter, and pings search engines with nobody pressing a button. A small, honest case study in spec-driven automation, told through the two nights it broke.

Work Part 6

The Marathon Session

Agents have no sense of time; ask one to work eight hours and it may finish in twenty. Stop estimating hours, write a real plan, and tell it to run a marathon session to the finish.

Work