latest / The new ratio of reading to writing code

Somewhere in the last eighteen months, the ratio of code I read to code I write flipped. It used to be maybe two-to-one — I’d read a fair bit of context before adding a function, but the bulk of the keystroke-time was mine. Now it’s more like eight-to-one. The bot writes a draft; I read it. The bot writes a test; I read it. The bot writes the explanation of why the test is right; I read that too, slightly suspicious.

The interesting thing is that the work hasn’t changed shape much. I’m still building the same kinds of systems, with the same kinds of bugs, on roughly the same kinds of deadlines. What’s changed is which part of the work is the bottleneck.

The bottleneck used to be typing the code. It really did. I would know exactly what I wanted to type, and the limit on my throughput was how fast my fingers could put it on the screen. That bottleneck is gone — not relaxed, gone — and what replaces it is something more like editing. Did the bot’s draft actually solve the problem I had? Or did it solve a problem that looked similar and you’d have to read carefully to notice the difference? That’s a reading problem, and reading is the slow part now.

Implications I’m still working out:

• The skill ceiling is higher, not lower. When the bot does the easy parts, the hard parts are all that’s left. Senior engineers are more valuable, not less.
• Code review has changed. It used to be partly a quality gate and partly a teaching mechanism. Now there’s also a third thing: a check that the human-shaped author actually understood the AI-shaped diff they’re submitting. That’s a new failure mode and we don’t have good norms for it yet.
• Comments matter more. A repo full of well-named identifiers and the occasional “why” comment is dramatically easier to navigate with AI than a clever one. The bot rewards legibility because legibility is what it eats.

I don’t have a tidy ending to this one. The shift is still happening. I notice it most when I’m tired and try to “just bash something out” the old way and find I’ve forgotten how. Which is fine, mostly. But I miss it a little, the way you miss handwriting.