TL;DR

A codebase can be read as a field that attracts future changes, and a pull request can be read as a force applied to that field.

A good field makes good changes easier to make. A bad field repeatedly makes bad shortcuts look natural. In an era where AI can produce PRs quickly, this attraction becomes stronger.

I call the practice of designing where future changes are pulled Attractor Engineering .

CI/CD, tests, reviews, and harnesses can be read as dissipative systems: they remove unwanted force and shape the trajectory.

ArchSig, or Architecture Signature, is a tool for observing that trajectory along multiple axes.

The first half of this article is written for practitioners: it explains the intuition in terms of codebases, PRs, review, CI, and AI-assisted development.…