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righthandyesterday at 5:36 PM2 repliesview on HN

But “are you really moving at speed after you generate the majority of your application?” is my other point. If you were to start working somewhere with an existing product the changes you would apply are more than likely incremental. What is the advantage of using LLMs to change 1-10 lines of code on average? How do you measure the ROI for that?

What did the time savings gain you? A quicker release date? How can you prove that? “This would have taken weeks” is the old problem of project time estimation. How can I take any engineer seriously that they think they know it saved weeks?


Replies

snomanyesterday at 6:33 PM

Considering that engineer never reliably estimated anything beyond a few days remotely accurately before… but now they can…

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hombre_fataltoday at 3:20 AM

> How can I take any engineer seriously that they think they know it saved weeks

Because we have experience doing things pre-AI.

For example, most projects had no tests before AI because tests are very time intensive and take a lot of forethought since you also need to engineer the code to be testable. Yet now tests are trivial. Every project I delegate to AI has tests. Good tests too. How do I know? Because I have 20 years of experience and I looked.

Or, fixing a bug in my codebase is as simple as copy and pasting the user's bug report email into Claude Code. The LLM verifies that the bug exists, writes a red test to ensure the bug exists, then proposes the best fix that will turn the test green. Meanwhile it did all this while I was doing something else.

Or, the projects I've built that would have taken me a lot of time because they are in domains I don't have much experience in. I built a macOS app around libghostty which involved bridging Swift to Zig, something I've never done before. And when Ghostty has new versions, I ask AI to look at the diff and find new features and APIs I can take advange of in my own project. I didn't write any code in this project myself. It would have taken me a lot of time because everything takes a lot of time. It makes progress on the project while I'm doing something else, yet I use the project as my main terminal every day, it's so good.

It's very wishful thinking to assume that nobody knows whether AI is helping them or not, probably coming from an understandable place where you hope all of this a fever dream and we'll go back to the old way any day now. But you owe it to yourself to believe others here so that you can take it seriously.