Code for Humans and Machines

Adam Tornhill · 3 Sept 2026

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Every claim below was made in this piece, quoted word for word and numbered in the order the piece makes them, so you can read it there rather than take our word for it. The sentence above each quote is our reading of the claim, not their wording. Each quote was checked against a stored copy of the page at build time; where the two differ, the quote is the fact.

Our reading
The incremental steps of Test-Driven Development are optimized for human cognition but do not survive the transition to agentic coding.

Their wordsThe incremental TDD steps were great for human cognition, but didn't survive the transition to agentic coding.
Our reading
In agentic coding, the primary audience for code is the machine rather than the human.

Their wordsWhat matters is that the code supports machine reasoning and change; the machine is the primary audience.
Our reading
Continuing to work in ways optimized for manual programming is unlikely to provide benefits in the era of AI agents.

Their wordsAgents are similar, and continuing to work in ways optimized for manual programming is unlikely to give us benefits.

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