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Re:Vibe coding and agentic engineering are getting closer th... by devin on Wednesday May 06, 2026 @12:12PM (#48037915)
> If you can go from producing 200 lines of code a day to 2,000 lines of code a day, what else breaks? The entire software development lifecycle was, it turns out, designed around the idea that it takes a day to produce a few hundred lines of code. And now it doesn’t.

It is so embarrassing that LOC is being used as a metric for engineering output.

Re:Vibe coding and agentic engineering are getting closer th... by ilikebits on Wednesday May 06, 2026 @12:17PM (#48037982)
LOC is useful here not because it's a metric for output but because it's a metric for _understandability_. Reviewing 200 lines is a very different workload than reviewing 2000.
Re:Vibe coding and agentic engineering are getting closer th... by jazzypants on Wednesday May 06, 2026 @12:19PM (#48038009)
That's assuming the 200 lines are logical and consistent. Many of my most frustrating LLM bugs are caused by things that look right and are even supported by lengthy comments explaining their (incorrect) reasoning.
Re:Vibe coding and agentic engineering are getting closer th... by mcmcmc on Wednesday May 06, 2026 @12:24PM (#48038077)
Ok? No one is saying that all LOC are equal. Ceteris paribus, 2000 lines is 10x more time consuming to review than 200
Re:Vibe coding and agentic engineering are getting closer th... by jazzypants on Wednesday May 06, 2026 @12:45PM (#48038363)
The point is that LOC is never a good metric for any aspect of determining the quality of code or the coder because it ignores the nuance of reality. It's impossible to generalize because the code can be either deceptively dense or unnecessarily bloated. The only thing that actually matters is whether the business objective is achieved without any unintended side effects.
Re:Vibe coding and agentic engineering are getting closer th... by mcmcmc on Wednesday May 06, 2026 @01:11PM (#48038716)
> The only thing that actually matters is whether the business objective is achieved without any unintended side effects.

Objectives change; timeliness matters. The speed at which you deliver value is incredibly important, which is why it matters to measure your process. Deceptively dense is what I’d call software engineers who can’t accept that the process is actually generalizable to a degree and that lines of code are one of the few tangible things that can be used as a metric. Can you deliver value without lines of code?

Re:Vibe coding and agentic engineering are getting closer th... by jazzypants on Wednesday May 06, 2026 @01:25PM (#48038904)
> Objectives change; timeliness matters. The speed at which you deliver value is incredibly important, which is why it matters to measure your process.

This assumes that shorter code is faster to write. To quote Blaise Pascal, "I would have written a shorter letter, but I did not have the time."

> Can you deliver value without lines of code?

No, but you can also depreciate value when you stuff a codebase full of bloated, bug-ridden code that no man or machine can hope to understand.

Re:Vibe coding and agentic engineering are getting closer th... by mcmcmc on Wednesday May 06, 2026 @01:59PM (#48039352)
You seem determined to misinterpret. I’m not talking about LOC as a measure of productivity. The ratio of LOC needing review to the capacity of reviewers (using how many LOC can be read/reviewed over the sampling period) is what’s being discussed. Agentic AI/vibe coding has caused that ratio to increase and shows a bottleneck in the SDLC. It’s a proxy metric, get over yourself.

“All models are wrong, some are useful”. What’s not useful is constantly bitching about how there’s no way to measure your work outside of the binary “is it done” every time process efficiency is brought up.

Re:Vibe coding and agentic engineering are getting closer th... by jazzypants on Wednesday May 06, 2026 @02:26PM (#48039771)
Yes, reading this back, I definitely veered off-topic. I apologize. I still don't think that you can say how much time it will take to review code based on how many lines of code are involved, but my argument was not well crafted. I just hope that others can learn something from our discussion. Thank you for being patient with me, and I hope you have a good day! :)
Re:Vibe coding and agentic engineering are getting closer th... by embedding-shape on Wednesday May 06, 2026 @12:44PM (#48038351)
> 2000 lines is 10x more time consuming to review than 200

Very far from the truth in practice, every line of code isn't as difficult/easy to review as the other.

Re:Vibe coding and agentic engineering are getting closer th... by jimbokun on Wednesday May 06, 2026 @01:48PM (#48039193)
But why would the lines in the 2000 case be easier to review per line?
Re:Vibe coding and agentic engineering are getting closer th... by squeaky-clean on Thursday May 07, 2026 @01:53AM (#48045905)
Which of these programs is easier to review

  {x{x,sum -2#x}/0 1}
or

  def f(n):
      if n <= 1:
          return n
      else:
          return f(n-1) + f(n-2)
They're both the same program
Re:Vibe coding and agentic engineering are getting closer th... by jimbokun on Thursday May 07, 2026 @08:26AM (#48048536)
Good question.

But it is orthogonal to the question of evaluating 2000 lines of AI code vs 200 lines of human written code. Either the human or the AI could produce idiomatic code for either language, given sufficient training data in the AI’s corpus for the language.

My guess is that the first one is much quicker to review, for a human equally fluent in both languages.

Re:Vibe coding and agentic engineering are getting closer th... by mcmcmc on Wednesday May 06, 2026 @01:54PM (#48039283)
Holy shit, read the words I wrote. Ceteris Paribus. Assume the 200 lines and 2000 lines have a similar distribution of complexity.
Re:Vibe coding and agentic engineering are getting closer th... by badc0ffee on Wednesday May 06, 2026 @05:46PM (#48042296)
Romanes eunt domus
Re:Vibe coding and agentic engineering are getting closer th... by moregrist on Wednesday May 06, 2026 @12:32PM (#48038189)
It’s still a bad metric.

I have worked with code where 1000s of lines are very straightforward and linear.

I’ve worked on code where 100 lines is crucial and very domain specific. It can be exceptionally clean and well-commented and it still takes days to unpack.

The skills and effort required to review and understand those situations are quite different.

One is like distance driving a boring highway in the Midwest: don’t get drowsy, avoid veering into the indistinguishable corn fields, and you’ll get there. The other is like navigating a narrow mountain road in a thunderstorm: you’re 100% engaged and you might still tumble or get hit by lightning.

Re:Vibe coding and agentic engineering are getting closer th... by lelandfe on Wednesday May 06, 2026 @12:39PM (#48038279)
There’s still a limit on how far one can drive in a day, no matter the road.
Re:Vibe coding and agentic engineering are getting closer th... by jimbokun on Wednesday May 06, 2026 @01:53PM (#48039269)
The number of bugs tends to be linear to lines of code written meaning fewer lines of code for the same functionality will have fewer bugs.

So I’m pretty skeptical that reviewing 2000 lines of code won’t take any more time than reviewing 200 lines of code.

Furthermore how do you know the AI generated lines are the open highway lines of code and not the mountain road ones? There might be hallucinations that pattern match as perfectly reasonable with a hard to spot flaw.

Re:Vibe coding and agentic engineering are getting closer th... by moregrist on Wednesday May 06, 2026 @08:31PM (#48043881)
> The number of bugs tends to be linear to lines of code written meaning fewer lines of code for the same functionality will have fewer bugs.

It depends on the code. If you’re comparing code of the same complexity then, sure, 2000 lines will take longer than 200.

I was comparing straight linear code to far more complex code. The bug/line rate will be different and the time to review per line will be different.

> Furthermore how do you know the AI generated lines are the open highway lines of code and not the mountain road ones?

Again, it depends on the code. Which was my point.

Linear code lacks branches, loops, indirection, and recursion. That kind of code is easy to reason about and easy to review. The assumptions are inherently local. You still have to be alert and aware to avoid driving into the cornfields.

It’s a different beast than something like a doubly-nested state machine with callbacks, though. There you have to be alert and aware, and it’s inherently much harder to review per line of code.

Re:Vibe coding and agentic engineering are getting closer th... by mrbnprck on Wednesday May 06, 2026 @12:44PM (#48038352)
Its still posssible to run any LLM in a loop and optimize for LoC while preserving the wanted outcome.
Re:Vibe coding and agentic engineering are getting closer th... by mcmcmc on Wednesday May 06, 2026 @12:18PM (#48037998)
Is it? The whole point of the article is that the rate of output for writing code has surpassed the rate at which it can be reviewed by humans. LOC as an input for software review makes a lot of sense, since you literally need to read each line.
Re:Vibe coding and agentic engineering are getting closer th... by adtac on Wednesday May 06, 2026 @12:18PM (#48038002)
LOC is the worst metric for engineering output, except for all the others - Churchill
Re:Vibe coding and agentic engineering are getting closer th... by deadbabe on Wednesday May 06, 2026 @12:25PM (#48038083)
The amount of times an engineer says what the fuck while reading code still seems like a reliable metric for code quality assessment.
Re:Vibe coding and agentic engineering are getting closer th... by dyauspitr on Wednesday May 06, 2026 @02:15PM (#48039600)
We won’t be doing that for much longer, enjoy it while you can.
Re:Vibe coding and agentic engineering are getting closer th... by seanw444 on Wednesday May 06, 2026 @07:45PM (#48043410)
Two more weeks!
Re:Vibe coding and agentic engineering are getting closer th... by deadbabe on Wednesday May 06, 2026 @09:54PM (#48044479)
I’m sure an agent can audibly play “what the fuck” as it crunches tokens reading through a codebase
Re:Vibe coding and agentic engineering are getting closer th... by AnimalMuppet on Wednesday May 06, 2026 @01:30PM (#48038956)
Somewhat reliable, yes. Not objective, though, and hard to reproduce.
Re:Vibe coding and agentic engineering are getting closer th... by deadbabe on Wednesday May 06, 2026 @02:01PM (#48039385)
In a world where everything is vibes now that doesn’t matter much.
Re:Vibe coding and agentic engineering are getting closer th... by etothet on Wednesday May 06, 2026 @12:16PM (#48037969)
Agreed. And, LOC has historically been one of the things we've collectively fought against management for how to evalute a "productive" developer!
Re:Vibe coding and agentic engineering are getting closer th... by ButyTh0 on Wednesday May 06, 2026 @12:38PM (#48038269)
Why?

We should have gone the other way; generated a lot of code and demanded pay raises; look at the LOC I cranked out! Company is now in my debt!

If they weren't going to care enough as managers to learn and line go up is all that matters to them, make all lines go up = winning

You all think there's more to this than performative barter for coin to spend on food/shelter.

Re:Vibe coding and agentic engineering are getting closer th... by embedding-shape on Wednesday May 06, 2026 @12:48PM (#48038409)
Because not everyone is just out after earning the most money, some people also want to enjoy the workplace where they work. Personally, what the quality of the codebase and infrastructure is in matters a lot for how much you enjoy working in it, and I'd much rather work in a codebase I enjoy and earn half, than a codebase made by just jerking out as many LOC as possible and earn double.

Although this requires you to take pride in your profession and what you do.

Re:Vibe coding and agentic engineering are getting closer th... by ButyTh0 on Wednesday May 06, 2026 @01:40PM (#48039097)
All of human agency must prop up the vanity of you. Of all people.

Got it.

...ok fine; lack of political action to put us all on the hook for your healthcare is your choice to take a gamble on a paycheck. It's a choice to say your own existence is not owed the assurance of healthcare.

So I will honor your choice and not care you exist.

Re:Vibe coding and agentic engineering are getting closer th... by christophilus on Wednesday May 06, 2026 @06:38PM (#48042838)
> in my debt

Good way of putting it.

Re:Vibe coding and agentic engineering are getting closer th... by estimator7292 on Wednesday May 06, 2026 @12:16PM (#48037972)
At least "mentions of LOC" is now a great metric for "how clueless is this person"
Re:Vibe coding and agentic engineering are getting closer th... by kashyapc on Wednesday May 06, 2026 @12:23PM (#48038067)
Totally. I thought Simon was wiser than this; even he couldn't resist getting swept up by breathless hype. The moment you start typing "LOC as a metric", alarm bells should go off in your head.
Re:Vibe coding and agentic engineering are getting closer th... by simonw on Wednesday May 06, 2026 @02:22PM (#48039703)
This was a podcast, not a pre-scripted talk. I suggest listening to the audio version - it makes it more clear that this was thinking out loud, not carefully considering every word.
Re:Vibe coding and agentic engineering are getting closer th... by kashyapc on Wednesday May 06, 2026 @02:27PM (#48039782)
I see, fair point. Sorry for taking a dig at you. Please know that I do appreciate a lot of work that you do. I was just worried for a moment when just reading that bit.
Re:Vibe coding and agentic engineering are getting closer th... by Daishiman on Wednesday May 06, 2026 @01:08PM (#48038674)
LOC is very much an effective metric for general productivity for the median feature. You can't code golf most lines of code out of existence.

We're also assuming LOC vibe coded by competent engineers who should be able to tell when something is overengineered.

Re:Vibe coding and agentic engineering are getting closer th... by jbeninger on Friday May 08, 2026 @05:55AM (#48060920)
Having worked with LLMs, you absolutely can golf most (>50%) lines of code out of existence. I regularly do, because it picks the wrong abstractions and sticks with them.
Re:Vibe coding and agentic engineering are getting closer th... by vrganj on Wednesday May 06, 2026 @12:29PM (#48038157)
I read somewhere that measuring software engineering output by LoC is like measuring aerospace engineering by pounds added to the plane and I thought that was an apt comparison.
Re:Vibe coding and agentic engineering are getting closer th... by root_axis on Wednesday May 06, 2026 @12:31PM (#48038178)
He's not using LOC as a metric, he's making an observation about the impact of a change in the typical volume of LOC.
Re:Vibe coding and agentic engineering are getting closer th... by faizshah on Wednesday May 06, 2026 @12:33PM (#48038205)
I experimented with vibe coding (not looking at the code myself) and it produced around 10k LOC even after refactors etc.

I rewrote the same program using my own brain and just using ChatGPT as google and autocomplete (my normal workflow), I produced the same thing in 1500 LOC.

The effort difference was not that significant either tbh although my hand coded approach probably benefited from designing the vibe coded one so I had already though of what I wanted to build.

Re:Vibe coding and agentic engineering are getting closer th... by embedding-shape on Wednesday May 06, 2026 @12:46PM (#48038377)
Sounds like a great oppurtunity to understand your own development process, and codify it in such detail that the agent can replicate how you work and end up with less code but doing the same.

My experience was the same as you when I started using agents for development about a year ago. Every time I noticed it did something less-than-optimal or just "not up to my standards", I'd hash out exactly what those things meant for me, added it to my reusable AGENTS.md and the code the agent outputs today is fairly close to what I "naturally" write.

Re:Vibe coding and agentic engineering are getting closer th... by 8note on Wednesday May 06, 2026 @01:48PM (#48039186)
or go with this, and use the agent to prototype ideas, and write it yourself once you know what you want
Re:Vibe coding and agentic engineering are getting closer th... by hungryhobbit on Wednesday May 06, 2026 @12:39PM (#48038281)
Humans are also incredibly varied and different.

Do you reject all stats that treat the number of people involved (eg. 2 million pepole protested X) as "embarrassing" ... because they lump incredibly varied people together and pretend they're equal?

Re:Vibe coding and agentic engineering are getting closer th... by dyauspitr on Wednesday May 06, 2026 @02:14PM (#48039580)
Honestly it’s more like 200 to a 100,000 of pretty decent quality code at this point.
Re:Vibe coding and agentic engineering are getting closer th... by keeda on Wednesday May 06, 2026 @02:21PM (#48039689)
LoC is perfectly fine as a metric for engineering output. It is terrible as a standalone measure of engineering productivity, and the problems occur when one tries to use it as such.

It's still useful, however, because that is the only metric that is instantly intuitively understandable and comparable across a wide variety of contexts, i.e. across companies and teams and languages and applications.

As we know, within the same team working on the same product, a 1000 LoC diff could take less time than a 1 line bug fix that took days to debug. Hence we really cannot compare PRs or product features or story points across contexts. If the industry could come up with a standard measure of developer productivity, you'd bet everyone would use it, but it's unfeasible basically for this very reason.

So, when such comparisons are made (and in this case it was clearly a colloquial usage), it helps to assume the context remains the same. Like, a team A working on product P at company C using tech stack T with specific software quality processes Q produced N1 lines of code yesterday, but today with AI they're producing N2 lines of code. Over time the delta between N1 and N2 approximates the actual impact.

(As an aside, this is also what most of the rigorous studies in AI-assisted developer productivity have done: measure PRs across the same cohorts over time with and without AI, like an A/B test.)

Re:Vibe coding and agentic engineering are getting closer th... by sva_ on Wednesday May 06, 2026 @06:07PM (#48042530)
I wonder if '2000 LOC' was chosen to refer to this old anecdote from the 80s:

https://www.folklore.org/Negative_2000_Lines_Of_Code.html

Re:Vibe coding and agentic engineering are getting closer th... by moomoo11 on Wednesday May 06, 2026 @06:51PM (#48042943)
I follow Garry Tan on X and he’s a big proponent of LOCmaxxing using AI.

AI helps eng ship more and faster, I think that’s the takeaway.

Re:Vibe coding and agentic engineering are getting closer th... by autoconfig on Wednesday May 06, 2026 @07:42PM (#48043384)
The charitable interpretation here is obviously that the LoCs are equivalent in quality, in which case it is a very useful metric in the context that was presented. The inability to infer that should be embarrassing.
Re:Vibe coding and agentic engineering are getting closer th... by jwpapi on Wednesday May 06, 2026 @07:53PM (#48043514)
I deleted 75000 lines of code of my codebase in the last 2 months and that was tremendously more useful to by business than the 75000 AI has written the 2 months before...
Re:Vibe coding and agentic engineering are getting closer th... by np1810 on Wednesday May 06, 2026 @11:15PM (#48045023)
I just read somewhere on HN that "code is a liability, not an asset, the idea behind the code/final product is the actual asset." And, I can't agree more...

> It is so embarrassing that LOC is being used as a metric for engineering output.

In one of my previous org, LOC added in the previous year was a metric used to find out a good engineer v/s a PIP (bad) engineer. Also, LOC removed was treated as a negative metric for the same. I hope they've changed this methodology for LLM code-spitting era...