The Living Codebase. Software in the Age of AI

For decades we built software by understanding it. With tools like Claude, Codex, and the chatbot now rewriting code almost as fast as we can read it.

Something has shifted in the way software gets made, and it happened quietly enough that most of us never stopped to name it. A few years ago, writing code meant designing it first: you held the shape of the thing in your head, argued with yourself about the structure, and settled the architecture before you typed a line. That deliberate, up-front way of working is fading fast. In its place is something looser and stranger, a process that has far more in common with tending a living thing than with drafting a blueprint, and it is worth being honest about how far the change actually goes.