alt.hn

6/9/2026 at 5:17:21 PM

What it feels like to work with Mythos

 https://www.oneusefulthing.org/p/what-it-feels-like-to-work-with-mythos

by swolpers

6/9/2026 at 7:32:51 PM

What I find fascinating that there is so little substance in this article about the quality of produced code and the medium. Is the code documented and tested? Is it understandable and extendable? Is it secure? What language, framework, database was used? Author mentions judgement and taste - well, is the code tasteful? Will the model rearchitecture the entire thing if I ask it to add new functionality, spending another 9.5h in tokens? I assume that the research part is domain knowledge = how different types of travel translate to time making it presentable; how did the author verify this?

These questions are even not about AI: if I were to give money to a human agency and were given something they tell me works, I would ask the same questions. If I did not know how to evaluate, I would hire people that do. With LLMs the verification part is what bothers me the most.

by eithed

6/9/2026 at 9:11:54 PM

These posts are never written by software engineers, it’s always some tech exec, retired engineer, or VC. This author is apparently a professor at the Wharton School of Management? None of these people have to ship or maintain real products, they’re just making side projects.

The only decent software engineering perspective I’ve seen has been from Mitchell Hashimoto.

by an0malous

6/9/2026 at 9:26:53 PM

Well that’s kind of the point.

They can just summon bespoke software out of the ether that only handles the use cases of themselves and a few of their collaborators.

Making “side projects” was mot possible for non-developers before powerful LLMs. Now it is.

by jimbokun

6/9/2026 at 10:32:04 PM

I don’t think that’s true, I think these authors are making a much stronger claim that AI is proficient or even an expert at software engineering. This author describes how complex and sophisticated their software is, and the only value he’ll concede to “coders” is that there might be a few bugs they’d need to fix.

Imagine not being an architect and using Claude to put together a building plan, then concluding it’s basically done but we might need a real architect to double check the measurements. It may even be true but I’d be skeptical if it’s always non-architects saying this.

by an0malous

6/10/2026 at 1:48:55 AM

Why do they even need coders to fix these bugs? It would be an order of magnitude (at least) to ask Claude to find and fix them, and it will likely be successful.

Building in the physical world has physical and time constraints that cannot be overcome, which is one of the reasons architecture (and engineering) are so important in this domain. In software development these constraints were only inherent when people were writing the majority of the software. I feel like I’m seeing what I thought were fundamental constraints being eroded by the increasing speed and correctness of these tools and it’s making me reconsider the importance of some of the values that are held by software engineering.

It’s obviously dependent on the domain and solution, but if your software can be extremely rapidly rearranged, bugs found and fixed with little effort, and features added with only a minimum prompt, I think the entire definition of technical debt has changed. I’ve been sceptical of these tools and still approach their output with caution. I also worry that, as a software developer, if more can be accomplished in less time there will be less room on this planet for software developers.

by bathtub365

6/10/2026 at 4:20:26 AM

> I think the entire definition of technical debt has changed. I’ve been sceptical of these tools and still approach their output with caution.

This very well summarizes my current thinking on the subject as well. And most of my career has been playing the role of technical debt nazi. Much to the detriment of my earning potential.

Does AI make incredibly inefficient code most of the time? Yup. But it does it at lightspeed with minimal effort.

I think many software engineers forget they exist to get real things done (in many cases at least) and they are a cost center for most businesses. If your end product is not selling software, very few people actually Doing the Thing(tm) will give a single solitary care about code quality or maintainability when they can just spend 30 minutes and $15 worth of tokens to fix it.

It won't take over everything, but I've already seen otherwise very intelligent go-getter type folks who are not technical or know how to code made extremely useful things for themselves and their small little enterprises. And this will seemingly only get better and more efficient.

For someone who really does love the idea of well architected and future-proof code this is just icky to even say or consider. But I'm coming around to this is the future for the majority of software for most places. And it may have the ability to seriously even the playing field for small enterprises in some industries.

I'm currently using it to implement a zillion side projects at home I've been "meaning to get to" for years. It makes incredibly silly unmaintainable code most of the time - but I learned to not care, and just tell the AI bot to fix it/add to it as I go along. Worst-case I spend a single night deleting it all and starting from zero to "refactor" an entire thing.

by phil21

6/10/2026 at 5:40:27 AM

> I think many software engineers forget they exist to get real things done (in many cases at least) and they are a cost center for most businesses. If your end product is not selling software, very few people actually Doing the Thing(tm) will give a single solitary care about code quality or maintainability when they can just spend 30 minutes and $15 worth of tokens to fix it.

I am suprised to hear people so naive they expect their token usage to stay flat if code quality and maintainability starts falling exponentially?

What if to fix 2 bugs your LLM starts adding 50 new ones? Will you tell your customers in supports channel "sorry software is finished, if we try fixing anything, everything else might break, not worth it". Or "we can probably fix it, but our AI usage will raise so much we need to up the subscription 3 fold, you choose".

The speed at which LLM codes is only comparable to the speed at which they add garbage to your repo. If you stop caring about maintainability, you also stops caring about your AI/LLM related bills and the viability of your project past the PoC stage.

by prmoustache

6/10/2026 at 6:30:00 AM

> Does AI make incredibly inefficient code most of the time? Yup. But it does it at lightspeed with minimal effort.

This hits the nail in the head.

Detractors often hang on to examples of coding assistants making mistakes or output subpar code, but they somehow miss the fact that coding assistants can also be prompted again and refactor whole swaths of code just as fast as they introduce oopsies. This means that the worst case scenario implies fast convergence to an acceptable outcome, and from there also fast iteration to improve upon that.

by locknitpicker

6/10/2026 at 10:04:32 AM

The problem is that this approach is not sustainable. Errors compound. The cost to fix one issue might seem small at first, but over a stretch of time all these "oopsies" become architectural spaghetti that can only be fixed with a complete rewrite, which will certainly become more expensive than getting the code "organically" developed.

The only way I see AI coding working in the long run is if we go back to a Waterfall/BDUF process and having actual engineering. Let engineers really own the architecture. Enforce that any new feature - no matter how small - to be specced out with complete sequence diagrams. Ensure that every new software package needs to be put on an UML component diagram for the team to review and see each addition interacts with the whole system, etc.

If we do that, then we can just give all the documents to a coding agent and say "go ahead and implement this" with a minimal amount of confidence. But in doing this, I bet we will realize the following:

    - the "effort" has never been about writing code itself. The code is just the material manifest of all the thought that went to think over a solution into the problems that the product is attempting to solve.

   - we will likely be better off by using code generation tools (i.e, UML-to-code) and a "weak" LLM (than can run locally) than by playing the token lottery at the Anthropic Casino.

by rglullis

6/10/2026 at 7:45:07 AM

I think this is overlooking the fact that assigning a coding assistant to fix the bugs it re-introduces for all eternity just leads to spiraling token costs, which might cost more than just hiring a competent engineer in the first place.

by asoderlind

6/10/2026 at 7:12:24 AM

Don't forget that you can adjust your requirements (either via plan or skill) to ensure the mistakes do not happen. The problem is that neither LLMs, nor humans (that don't work with the domain) will know they made these mistakes. Even coders don't think about everything all the time

by eithed

6/10/2026 at 7:15:04 AM

I haven’t used Fable/Mythos yet, but my experience with recent version of Opus, GPT 5.5 and recent Chinese models is that promoting again isn’t guaranteed to fix the underlying issues, nor is it guaranteed to not introduce more issues. I’ve seen SOTA models make ridiculously stupid architectural decisions that they were then unable to back out of without being prompted very specifically, instead adding a patchwork of “fixes” on top.

I’m not saying that you can’t use AI to do it because I believe that with carefully controlled workflows and context management you can, but it’s not a simple prompt away, it’s requires guidance and understanding, and isn’t the speed demon that raw prompting is.

by dkersten

6/10/2026 at 7:26:33 AM

> I haven’t used Fable/Mythos yet, but my experience with recent version of Opus, GPT 5.5 and recent Chinese models is that promoting again isn’t guaranteed to fix the underlying issues, nor is it guaranteed to not introduce more issues.

That's not really the point though. That presumes models are only useful if they are one-shot models. That is false.

I mean, what if your prompt successfully changes 20 source files and makes a mess in one? How much work did it saved?

And the elephant in the room is when models actually outperform whatever the prompter is able to deliver, and faster. That is somehow left out.

by locknitpicker

6/10/2026 at 7:49:55 AM

> That presumes models are only useful if they are one-shot models

That’s not at all what I’m saying.

I’m saying that in my experience across multiple models, the follow up prompts don’t fix prior underlying issues. They usually patch on top instead, unless you give them significant and time consuming guidance.

I want them to be more useful outside of one-shot uses, but I find that they currently miss the mark.

by dkersten

6/10/2026 at 7:34:08 AM

In my experience, the refactors are just as bad, just in different ways. All you end up doing is treading water with different iterations of shitty code. By the time you get somewhere acceptable, you could've just fixed it up yourself.

My preferred workflow these days is to pair program with an LLM until it gets close-ish and then manually touch it up. Without that, it just produces junk in different forms.

by vrganj

6/10/2026 at 9:13:27 AM

And - we kind of have been here before. The "proto"-type is almost complete. Its just a little slow, a little spaghettificated, just written in excel-vb, clicked together in node-graphs, or the next hot thing that makes coding unnecessary.

by 21asdffdsa12

6/10/2026 at 9:19:23 AM

> I think these authors are making a much stronger claim that AI is proficient or even an expert at software engineering.

The author specifically says:

> I am sure it is not perfect (I only spent an hour working with the results), but a software engineer would iron out the remaining potential bugs that I could not find quickly (which is one reason we may need more, not less, coders in the future, to help with the explosion of new uses for software)

which acknowledges pretty clearly that engineers bring a level of insight and experience still missing from Mythos. Saying that, I totally disagree with his contention that this will always be true. It's pretty weird that the author of an article stressing the steep improvements in a model's capability can't seem to imagine further improvements in that capability. As if Mythos is where development ends or whatever gap remains between models and experts won't steadily narrow or eventually widen in reverse.

by squidbeak

6/10/2026 at 6:07:18 AM

Well, right, but if the real use case for LLMs is "making software that wasn't economical to make before" that's bearish for the labs because it means they're only going to be chasing the low end of the market.

by bandrami

6/10/2026 at 3:15:01 AM

It is, and it's cool that it is, but the calibration is important. Statements like this:

> With Fable the spell has gotten powerful enough that I am no longer sure I am the wizard. I am closer to a patron. I describe what I want, I pay for it, and I judge the result. The conjuring happens somewhere I cannot watch, in hundreds of small choices I never get a vote on. The work has shifted from process to outcome. I no longer steer; I commission.

have a very different meaning coming from a non-technical researcher than they would from someone who builds software for a living.

by SpicyLemonZest

6/9/2026 at 10:24:27 PM

Making side projects isn't a trillion dollar industry tho, adding to the fact that we are facing another global supply chain crisis due to the Iran War; the US is about to commit the biggest self-own ever in the history of empire.

by shimman

6/10/2026 at 9:09:38 AM

The US has been on a course of self-owns ever since Trump got into office. That they still are a dominant power on the globe shows how much they were one before Trump, but it seems to be changing. At every self-own they commit, China laughs and inches up a little closer. I think we will see the day, when they are evenly matched in our lifetimes.

But which self-own exactly do you mean, of the many there are?

by zelphirkalt

6/9/2026 at 8:26:23 PM

I’m starting to realize that LLMs are really good at building low-stakes projects. Your questions mostly presume that the stakes are higher. The software will last a long time; the requirements will evolve; we can’t tolerate mistakes; etc.

The trick to getting good at using LLMs for software is to learn how to make _all_ projects low-stakes.

by cgearhart

6/9/2026 at 8:34:12 PM

You don't need LLM for that. You make _all_ projects low-stakes by working on green field project using (insert buzzword soup of the day) and leaving for a new green field opportunity (that requires experience with buzzword soup of the day) before the project ships.

by qaq

6/10/2026 at 2:26:09 AM

No, what you’re describing still requires you to do some actual work, and also, while you work there, there is still some level of accountability. A much, much better grift is coaching.

Like, an AI coaching session for executives at the yearly executive retreat. You show up, spend a few hours going through some nonsense slides ChatGPT put together for you, you charge an eye watering fee for it, HR or whoever organizes it will gladly pay for it because it will make them look all cutting edge in front of the CEO, by the next day everyone will forget about it. No accountability at all!

by DrJokepu

6/10/2026 at 5:07:58 AM

In the LLM world you never get a chance to get paid to work on those greenfield projects because the person with the idea is churning the prototyping and discovery work themselves.

If you want to get paid to work on software, you get involved after its found success and the stakes get higher.

(Which assumes there are still significant areas where economies of scale reward that vs everybody just having their own DIY version of everything.)

by majormajor

6/10/2026 at 5:21:05 AM

Or economies of liability and buck passing. I suspect managers and businesses will still want to be in the game of "not my fault, supplier is working on it, we can sue them if they don't meet SLA".

by owlbite

6/10/2026 at 2:12:22 AM

If there's a viable way to make all projects low-stakes we'd have done it. Consider this: microservices.

by dchftcs

6/9/2026 at 10:31:10 PM

This is really insightful, but I think it also extends to making the project either low stakes or low complexity. I have this lurking feeling that the preferable architecture for software will change as a result of LLMs because they're good at working on low complexity modular components more than they are on high complexity million-line code bases.

by rpdillon

6/10/2026 at 2:21:09 AM

You'll just shift complexity to the orchestration of the modular components.

Monoliths vs micro-services.

by ncruces

6/10/2026 at 5:08:43 AM

They aren't necessarily as great at building low-complexity high-modularity components, though. ;)

Unless you know enough to tell them to! And keep them honest about it...

by majormajor

6/9/2026 at 8:31:58 PM

> The trick to getting good at using LLMs for software is to learn how to make _all_ projects low-stakes.

this doesn't really work in the real world. There are many things that actually matter, engineering is fundamentally about handling them.

by acedTrex

6/10/2026 at 1:10:20 AM 

    the quality of produced code and the medium
A thought I have been tossing around in my head as the models get better is that it really may not matter what the code looks like.

If the observed behavior of the software is good, then the software is good. If a bug, of whatever kind, can be fixed by a model on a vibe-coded codebase, then that's a fixable bug. If there are no exploitable vulnerabilities, then the code is secure. If the performance is adequate, then the code is performant.

It simply does not matter what the code looks like if, from the outside, it does what its supposed to, and, from the inside, a model can fix the issue if one is found.

More than ever, software engineering is now really a job about making sure the code is doing what its supposed to.

And even if it DOES matter what the code looks like, you can have a model fix that too.

by spicyusername

6/10/2026 at 2:25:43 AM

The thing is that a lot of code rely on multiple layers of abstractions with their own correctness and failure states. And then you overlay the domain correctness and failure cases on top of that.

But all of those correctness are imaginary. The hardware only enforce a few (and it may be buggy). The OS adds some more (and it’s buggy). The compiler/interpreter may have bugs (but that’s rarely a nuisance) and the libraries are often brittle. There are cracks everywhere in the tower of abstractions.

The code has never mattered. What has always mattered is the knowledge of what is the model of correctness of the software (programming as a theory by NauR), so that you can discern where a program is wrong.

The thing is a crash or some other immediate errors are actually nice to have. You get to react immediately and can have a core dump or a stacktrace that points you the error. What is truly a terror is silent corruption (wrong order of operations, wrong values for a comparison that has expanded the idea of correctness, security issues that has been backdoored for years,…).

As Hoare said:

  There are two ways of constructing a software design: One way is to make it so simple that there are obviously no deficiencies and the other way is to make it so complicated that there are no obvious deficiencies.
  The first method is far more difficult.
LLM are very much the second kind. You write a lot of complicated code, and then you can no longer reason about their correctness.

by skydhash

6/10/2026 at 5:28:44 AM

> There are two ways of constructing a software design: One way is to make it so simple that there are obviously no deficiencies and the other way is to make it so complicated that there are no obvious deficiencies. The first method is far more difficult.

That is so real. Brilliant !

by gofreddygo

6/9/2026 at 9:01:53 PM

>What I find fascinating that there is so little substance in this article about the quality of produced code and the medium.

I clicked one of his examples intrigued "a snake game where the snake is self-aware and crazy things happen;". Played for 1-2 minutes, and it's the classic 1980s snake game. Am I missing something? What is "self-aware" about it? Some funny messages at the bottom of the screen? And what are the "crazy things"?

by coldtea

6/9/2026 at 9:57:46 PM

It sounds like you either didn't play enough or you are missing the new mechanics that get added over time. There's definitely more to it than just regular snake.

by starshadowx2

6/9/2026 at 9:35:20 PM

I had the exact same thought. To me, it feels like they just took the fairly common “sentient video game character” trope and bolted it onto a very conventional snake game.

I will say, the act of eating creates a "bulge distortion" that flows down the length of the snake is a nice touch though.

by vunderba

6/10/2026 at 2:24:37 AM

You didn't play long enough. There are layers and layers and layers of features in that game if you play for 10 minutes or more.

by kesor

6/10/2026 at 3:05:33 AM

Can you spoil it for us?

by nozzlegear

6/10/2026 at 1:41:05 AM

Welcome to every LLM discussion in the past 2 years or so. When asked for anything of substance, we're faced with a barrage of "but humans aren't good at this too!" Very few quantifiable evidence and lots of pure rhetoric.

by soraminazuki

6/10/2026 at 10:12:38 AM

Yeah, never concrete examples from these guys.

I am creating a game and I can say that with the coding part the models help a lot, mostly gpt 5.5 high. Tbh to me all the frontier models feel the same and they can all solve the stuff I do quite well with some guidance and prompting. But that kind of makes me appreciate the other stuff more like visual style, sound design, mechanics etc etc. Tons of work still.

For brainstorming I find the models bad nowadays or maybe I am just too critical of the results

by viking123

6/10/2026 at 1:51:04 AM

I’ve seen this pattern again and again, and I don’t bother replying. There’s also the “strong statement, and when you contradict it, they point out some particular circumstances that no one cares about”.

by skydhash

6/10/2026 at 9:56:48 AM

I think a lot of us have stopped talking to each other about this. I see it the other way round to you. I see constant scepticism and doubt that LLMs can build anything useful, and whenever provided with examples, the goalposts just move.

And at my own firm, I think every developer is generating most of their code using agentic coding. We're still sceptical enough that we are doing the usual heavy handed human review process, so we're not seeing a huge speed up in delivery times, but we are seeing a volume increase. That is because writing the changes and raising the PRs is much faster, but also a lot of boring admin and support work is now mostly done by LLMs. Reports of instability, vague client requests, etc? Throw the LLM at them and it usually figure it out why I continue to engineer.

So I know, first hand, that these things are very good. I also know second and third hand that pretty much every fintech in the industry is as heavily using agentic coding as we are.

And then I come to HN or reddit and I see people telling us that they cannot write decent production code, and this is just wrong. This isn't opinion wrong, it is objectively wrong. Any fintech that wants to keep up will tell you this.

I can't speak for other industries but I can't imagine they're different.

So, I'm not sure what to conclude from this. I don't want to be uncharitable, but when HN/reddit posts just don't match the reality I see for myself, I have no choice but to categorise them as being emotionally driven to stick to a particular narrative, and so I can dismiss them.

by munksbeer

6/10/2026 at 4:36:57 AM

These days it's uneconomical for human to verify AI generated code. So we ask the AI to do it. Like when we asked the FBI to audit itself and they found no problems :)

by andai

6/9/2026 at 7:36:15 PM

Being the first to release an article gives you great SEO or whatever. Doing the things you've mentioned takes time.

by hypfer

6/9/2026 at 7:50:29 PM

Less fascinating when you consider that this is a non-coders perspective.

by jstummbillig

6/10/2026 at 5:50:29 AM

It's still fascinating, but for a different reason. The "Concord" tool that got created bills itself as "Instrument-grade measurement of qualitative text. Explore in minutes, publish with honest statistics." Instrument-grade! How wonderful! That presumably means its accuracy has been ensured, and it's been carefully calibrated, right? What, nobody's ever measured or even examined the code? Well, no matter, let's go ahead and publish it and advertise it as "honest" "instrument-grade measurements."

by CobrastanJorji

6/9/2026 at 8:13:21 PM

Fair enough, but enterpreunership should, I guess, ask questions if given Next Big Thing has substance behind it or is it just snake oil.

by eithed

6/9/2026 at 8:27:32 PM

Ah, but billions of dollars depend on those questions not being asked in a genuine manner. Don't you want a slice of that or are you an... AI skeptic thunder clashes.

by munk-a

6/9/2026 at 9:08:19 PM

Yeah, this made it basically clickbait for me, in terms of time I wasted with the wrong expectation.

The lack of downvotes on posts on HN has always felt like more of a bug than a feature to me.

by unholiness

6/9/2026 at 8:41:20 PM

So, the perspective of the one that gains the most, that will value this the most, and that will pay the most? ;)

by nomel

6/9/2026 at 10:39:26 PM

You probably don't care about the ingredients or engineering of asphalt, only if the road does its job well or is filled with potholes. Outside of the software industry, nobody gives a shit about code or databases.

by chickensong

6/10/2026 at 6:16:39 AM

> You probably don't care about the ingredients or engineering of asphalt

Everyone does. You don’t think about it everyday because we’ve delegated it to experts which don’t come up with a new composition of Asphalt every time you press “generate”. It’s rigorously battle tested and short of intentional negligence, it’s consistent. I’m amazed how people are forgetting how the world actually works.

by geraneum

6/10/2026 at 7:20:35 AM

Exactly - the normalization of craft (?) is interesting

by eithed

6/10/2026 at 7:28:48 AM

You've missed the point.

by chickensong

6/10/2026 at 8:10:05 AM

The point doesn’t seem to have been thought through.

by geraneum

6/10/2026 at 10:02:46 AM

The point is, if road engineers changed their process and materials, and to you it felt like driving on the same road, with the same wear and tear and potholes, you wouldn't even notice.

If AIs can generate code that looks ridiculous to humans but over time has the correct performance, the correct behaviour, no-one outside of software engineers will know or care.

by munksbeer

6/9/2026 at 10:48:59 PM

I agree. But if I'm paying for the road (even as a taxpayer) I get angry that after a year it's full of potholes and that there are unnecessary signs warning about penguin crossing, making it cost 2 times more than it should have (and dont get me started why this road is really a highway leading to my house). I'd want certain qualities. And this article is basically = you will get a road, built quickly

But yes, you are right - I don't build roads and don't know what is a price to build a road and how to determine the quality of correctly built one, nor I will ever care or learn.

by eithed

6/10/2026 at 4:41:21 AM

> And this article is basically = you will get a road, built quickly

That's not how I am reading it. You will get a road built exactly to your spec, quickly. So no penguin crossings unless you ask for them.

I am also not entirely sure how the pothole argument translates.

by aix1

6/10/2026 at 6:05:16 AM

The road will be built to some specs, including features nobody asked for. If the corpus was trained for roads built in Arctic, you will get penguin crossings.

by eithed

6/10/2026 at 12:37:50 AM

The ingredients and composition of the tarmac is the difference between having the road full of pot holes after a week of use

by Tylerian

6/10/2026 at 2:43:25 AM

Sure, but if there's a trillion dollar company saying that it's going to replace all our road workers or engineers - I'd want to listen to the opinion of an expert. Some reporter from CNN driving over it like "yeah seems good to me, good this" has approximately zero persuasive power to me.

by fwip

6/10/2026 at 7:22:53 AM

It still does make errors, yes? Because it is not usable, if we need to verify everything. AI is only interesting if it can do things that humans can not do. If you can verify results because you can do it yourself, then why use AI? It will just bind highly skilled people to do verification work. Instead these people should do the actual work, results will come quicker.

So AI is only interesting to you / your org / humans if it can do things that you can not achieve. But if it still does errors, how could we ever know that super-invention by AI is not wrong?

If we can not rely on the correctness of the result, it is not usable at all. AI must create reliable and correct results always. That was a very fundamental requirement for computing. This problem has not been solved.

by sexylinux

6/10/2026 at 3:36:19 AM

So would you be more comfortable if the user them just prompted the AI to use a specific language, framework and database. Aren't we all just going to reddit and finding out what all goes best with what? But also I don't trust nothing from it, even though I've seen it.

by markoloko

6/9/2026 at 9:24:11 PM

Does it matter to the people requesting the software if it acts in the way they expect?

by jimbokun

6/10/2026 at 2:56:49 AM

We've lived in a software bubble for so long, most software engineers have completely forgotten that the purpose of (most) software is to solve a problem. If that problem solves the problem well and reliably it doesn't matter the quality of the code.

In fact, that's the entire reason we care about "quality code", because we assume that quality code is code that does what you expect well and consistently.

I say this as someone who hand writes code pretty much every night for fun, just to experiment with computation. Which, oddly, is more fun than ever because I don't feel like there's any need to connect this type of programming with "real world software", and I can really enjoy code for it's own sake, meanwhile my job is mostly just running agent loops (which I quite like as well).

by crystal_revenge

6/10/2026 at 10:06:11 AM

Exactly. Quality of code is a programming invention to make it easier to write and maintain correctly functioning applications.

That is the entire purpose of "quality of code".

If the end user experiences a correctly performing application, now, and in the future, they don't care at all what the code looks like.

AIs could resort to a single global array of primitives and forget all about functions, and just use gotos if it helped them (it probably doesn't).

by munksbeer

6/10/2026 at 3:26:48 AM

I haven't forgotten that, I affirmatively think it's false. High quality code is necessary to solve problems reliably. Perhaps some people call things code quality when they don't matter (I really don't care what most variables are named), but there have always been teams who try to increase velocity by disregarding code quality, and from what I've seen AI does not stop them from shipping outages constantly.

by SpicyLemonZest

6/9/2026 at 10:34:00 PM

True, but you should say that about every thing. Does it matter to you how the car drives, as long as it takes you to your destination? Well, yes, it matters: how will it deal with a crash, and if it's possible to replace a part and if anybody can just open it if you leave it outside. I will be amazed if somebody shows me their home-printed car, but if they'll try to sell it to me like a new one...

by eithed

6/10/2026 at 6:43:09 AM

Don't harsh my vibes, man.

by otabdeveloper4

6/9/2026 at 8:24:14 PM

It's an ad.

by grafporno

6/9/2026 at 7:58:02 PM

I'm becoming more convinced these are questions of the Before Times. Yes, yes—heresy, I know.

Yet, I can't deny the reality that I observe working with LLMs every day. If this truly is a step-function (as some are sgguesting), then I have absolutely zero concern for the quality of the code.

by adamtaylor_13

6/10/2026 at 2:46:41 AM

Kind of a circular argument, isn't it? "Some people are saying it's very good at coding. If that's true, I don't care if the code is good."

by fwip

6/9/2026 at 7:18:07 PM

Anecdote: I fed Fable some models I’ve been hand verifying (basically, I sketch out a scenario for Opus to model, it builds it, I ask it to show me the math, I correct it, we iterate like this, then I double check its code to make sure the math matches the model logic). Fable found almost every error I found, and then had some interesting suggestions for additional variables.

It also burned through my usage quota like a late-90s Hummer.

by JumpCrisscross

6/9/2026 at 9:23:21 PM

> It also burned through my usage quota like a late-90s Hummer.

Yeah. I have a Max 5x subscription and Fable burned through 16% of my weekly quota in a 40 minute code review session. It didn't even finish the review, it switched back to Opus 4.8 in the critical memory safety parts where I actually needed Fable.

I feel like I'm going to get priced out of these models soon. I should probably try to get the most out of Fable until June 22nd.

by matheusmoreira

6/9/2026 at 7:30:03 PM

now for the best question: whats your ROI here?

by cyanydeez

6/9/2026 at 8:19:49 PM

Humans are very expensive, so the equation almost always falls against them.

It's not just salary, but also safety/labor regulation, legal risk, vacations, sick time, personal conflicts, HR, benefits.

Even when automation is more expensive on paper, it's generally still cheaper

by Ferret7446

6/9/2026 at 11:10:54 PM

> Humans are very expensive, so the equation almost always falls against them.

You underestimate what these models cost. Uber's budget is $1,500/dev/month. I gather that was put in place because the dev's were going through $6,000/dev/month, which Uber decided could not be cost justified.

Fable costs at least twice as much, or $12,000/dev/month.

Fable can apparently work for hours without supervision, which means a skilled engineer can now have it working on many tasks concurrently. I would not be at all surprised if they can put a nought or two on that number. If you do that, you are well out of "what a human costs" territory.

by rstuart4133

6/10/2026 at 10:10:16 AM

> You underestimate what these models cost. Uber's budget is $1,500/dev/month

$1,500/month needs to be contextualised against the fully-loaded cost of a software engineer. Uber's average TC for a software engineer is around $350k, the fully-loaded cost is going to be in the $450k-$500k range. So we're talking around $38k/month for a software engineer.

$1,500/month isn't even a drop in the bucket. If LLM use lets them shave just one person off a team, that pays for tokens for the next 25 engineers.

by swiftcoder

6/10/2026 at 9:28:18 AM

Not to argue myself out of a job, but I cost around $20k/month, all costs considered(taxes, social fees, PTO, healthcare, benefits). If my efficiency is tripled(which it absolutely is, even before fable) for a mere 6k/month(in reality, 1k is more than enough though), that's ~10x ROI.

I kinda get why execs are excited

by amarant

6/10/2026 at 8:28:32 AM

These numbers don't mean anything without a denominator. You could burn $10 million/month of tokens if you want. We want to know how the cost per unit of useful output compares to a human. Does $6000 of usage buy you a man-month of work? Less? More?

by nearbuy

6/10/2026 at 6:23:02 AM

Minor note, 2x $/tok is not 2x cost. Personally, I see Fable being significantly more token-efficient than Opus 4.8. Then, there's also the compounding costs of quality.

by winwang

6/10/2026 at 9:28:04 AM

On top of which, as the article mentions, it delegates simpler tasks to cheaper models.

by squidbeak

6/10/2026 at 3:27:22 AM

> I would not be at all surprised if they can put a nought or two on that number.

People keep saying this and it keeps not happening.

ChatGPT Pro was $200/mo when it launched in '23 for a ~100B class model with 8k context. Claude Max is now the same price for practically unlimited access to a ~1T class model with 1M context.

Moore's Law never died, it just switched architectures.

by ramesh31

6/10/2026 at 10:13:01 AM

Not to mention, the cost/performance of the baseline keeps falling. The cost-effective Deepseek V4 Flash is better than frontier models from a year ago, at a fraction of the cost.

by swiftcoder

6/9/2026 at 9:56:20 PM

Good to know that LLMs will be removing all regulatory and legal risks, as well as creating a consumer economy that no longer employs or pays consumers.

I can't help thinking there might be some kind of strategic issue here.

Perhaps someone should ask Mythos about it.

by TheOtherHobbes

6/10/2026 at 1:56:42 AM

By the point where we have work hours regulation for AI, all of our current debate about AI will be long irrelevant because we've clearly achieved AGI

by Ferret7446

6/9/2026 at 10:50:44 PM

One of the large (and enjoyable IMHO) challenges in this line of work is developing a de facto understanding of your process and the context it's in service to, and that's only possible if you're actually on your industry equivalent of a "shop floor" for each domain the project touches.

As far as I can tell this part of the job isn't really on anyone's radar anymore.

by gopher_space

6/9/2026 at 8:35:30 PM

That's the beauty of these AI advancements. You, a human, will have to compete against a model for the same job.

If you get $100,000 per year as a SWE, and Anthropic offers a coding model for $100,000 per year (but working 24/7), then you'll have to give up all of those addons that make the fully burdened cost of the employee. Say goodbye to vacation, sick time, benefits, etc.

by warkdarrior

6/10/2026 at 2:47:41 AM

> "What have you got against machines?" said Buck.

> "They're slaves."

> "Well, what the heck," said Buck. "I mean, they aren't people. They don't suffer. They don't mind working."

> "No. But they compete with people."

> "That's a pretty good thing, isn't it--considering what a sloppy job most people do of anything?"

> "Anybody that competes with slaves becomes a slave," said Harrison thickly, and he left.

Kurt Vonnegut, Player Piano

by rspeele

6/10/2026 at 5:41:06 AM

They will do it for far less. Once manufacturing catches up and they have the data centers built out tokens are going to be dirt cheap.

by dyauspitr

6/9/2026 at 8:12:19 PM

It just got released, it shouldn't matter.

We know this model will be cheaper and faster with time.

And we have not even reached the timespan/timeframe were we have ASIC style models.

OpenAI has to do something which will beat Fable otherwise Anthropic won. China currently overtakes cars, pv, batteries and very soon silicon chip making, it has all the incentive to also take over AI.

by Qhemlomo

6/10/2026 at 1:33:21 AM

> We know this model will be cheaper and faster with time

Why? Demand for AI compute seems to be increasing faster than new production is due to come online for the foreseeable future, particularly if more-intensive models induce demand.

by JumpCrisscross

6/9/2026 at 8:16:40 PM

LOL magical thinking

by camillomiller

6/9/2026 at 8:19:59 PM

I'm happy to discuss arguments if you want to add any?

by Qhemlomo

6/9/2026 at 9:05:37 PM

Not OP, but for me, this model will get VERY expensive in 2 weeks. Now it is part of Pro plan, after 22nd it will get excluded and I will pay by token API usage (~10x more expensive).

I find it good for code reviews.

by throw939494555

6/10/2026 at 7:16:03 AM

Yeah my time scale is 'a handful of years' :)

by Qhemlomo

6/9/2026 at 8:32:48 PM

The only thing they’ve overtaken is arguably batteries, and even that is questionable if the quality is as good as Korean manufacturers. I think it’s more likely that the Chinese chip industry overtaking competitors will remain like nuclear fusion, forever “just 5 years away”

by Our_Benefactors

6/10/2026 at 9:45:31 AM

The best batteries are currently from CATL. No one in the industry is doubting this.

Huawei just showed LogicFolding and have a roadmap for 1.4 nanometer by 2031; SMIC is going for 5nm.

And all of this WITHOUT EUV.

by Qhemlomo

6/10/2026 at 8:43:30 AM

They mostly have overtaken in cars too. Their EVs are just cheaper, and they have built the infrastructure around it, even in more rural provinces. Building infrastructure is something they excel at anyway.

by zelphirkalt

6/10/2026 at 3:01:50 AM

The parent comment is describing a test they ran so they could assess their trust in the model for scenarios they don't have time to fully understand.

Do you not believe in running tests, evaluations, or experiments at all to better understand your environment?

The ROI in the case of a positive outcome is the reduced time needed to inspect the results in the future (the entire point of AI is to know what you can trust it on, so you can delegate everything at that level with less oversight). The ROI in the negative case is the tokens not wasted on tasks to ambitious for the model.

by crystal_revenge

6/9/2026 at 7:38:25 PM

It will be great when the price of compute/memory drops to normal level!

by PunchyHamster

6/9/2026 at 9:27:46 PM

>Sam Altman has signed another Memoranda of Understanding: Buying all SDRAM till the heat death of the universe OR Musk relocates to mars.

by cyanydeez

6/9/2026 at 8:00:13 PM

This little line from the article scares me: "but a software engineer would iron out the remaining potential bugs that I could not find quickly"

Every sw dev knows this is a very dangerous, and unrealistic, assumption.

by olafmol

6/10/2026 at 6:22:13 AM

it's basically a tiny statement that kind of hand waves all the 'actual stuff'.

by bluegatty

6/10/2026 at 7:23:16 AM

It's "I did the first/easy 90% now someone else do the second/hard 90%". Same as it ever was.

by BigJono

6/10/2026 at 8:49:53 AM

We're not supposed to be crude on HN but that's some real Dilbert level stuff right there. Like spit out my coffee laughing, cringing. It's too bad the Dilbert guy seemed to have lost his mind in meta level cynicism (and maybe his legacy as well) and also passed away, because we kind of need him now. Dilbert is almost made more for the AI age than the computing age.

by bluegatty

6/10/2026 at 5:29:12 AM

Desperate to know what the prompt for the poem is. The idea of it felt familiar so I went down the rabbit hole and found: 14 years ago, a poem on reddit [https://www.reddit.com/r/RedditDayOf/comments/tjjw2/may_12_a...] . Nowhere near the length of the one the author shared but the same idea.

> This is from "The Cyberiad", a collection of science-fiction fairy tales by Polish author Stanislaw Lem ... In one of the stories, a robot constructor named Trurl creates a machine that writes poetry. A jealous rival named Klapaucian challenges the machine to compose "...a poem about a haircut! But lofty, noble, tragic, timeless, full of love, treachery, retribution, quiet heroism and in the face of certain doom! Six lines, cleverly rhymed, and every word beginning with the letter s!!"

And the computer responds with:

"Seduced, shaggy Samson snored.

She scissored short. Sorely shorn,

Soon shackled slave, Samson sighed.

Silently scheming,

Sightlessly seeking

Some savage, spectacular suicide"

The author had to be referencing this moment in their challenge to Fable/Mythos. I'm curious to know what their exact prompt was.

by nstart

6/10/2026 at 9:41:33 AM

What's fascinating is that this is the difficulty of English translation -- which uses a different start letter and different words than the Polish one:

  Cyprian cyberotoman, cynik, ceniąc czule
  Czarnej córy cesarskiej cud ciemnego ciała,
  Ciągle cytrą czarował. Czerwieniała cała,
  Cicha, co-dzień czekała, cierpiała, czuwała...
  ... Cyprian ciotkę całuje, cisnąwszy czarnulę!!
You can consider the job of a translator as compared to LLM. Both derivative works, working within some constraints but with room for creativity.

by Erwin

6/10/2026 at 8:53:35 AM

> the author had to be referencing this moment in their challenge to Fable/Mythos.

Or it just swept it up in the training data given Anthropic license Reddit comments.

by philipwhiuk

6/9/2026 at 7:57:20 PM

Reading the first few paragraphs of what he calls "the most sophisticated academic social science paper I have yet seen from an AI" does not impress as much as I hoped.

"Posterior beliefs about market demand are purely referencedependent: holding dollars raised constant, they track only performance relative to the founder’s self-chosen goal—jumping half a standard deviation at the threshold, responding steeply for the first ten points past it, and flattening thereafter"

Humans generally don't verbalize data this way. The summary document is also very fluffy.

by ecocentrik

6/9/2026 at 8:35:57 PM

[dead]

by huflungdung

6/10/2026 at 7:50:16 AM

As a software engineer and solution provider, I do not feel threatened by this.

I do not fear that management will get tools like Mythos and then not need people like me. Most of the value I provide is in translating what the management/client _thinks_ they need into what is the real problem and solution.

That's not an insult to them, it's just pointing out that they see only their problem, and they imagine what would be the solution. They then ask for that solution. Quite often, what they want built isn't what they need. And I've seen so many problems, from so many domains and scenarios, that I can usually recognize the core need and propose (and build or direct building of) a solution which resolves that need AND has an eye toward the likely future needs.

Mythos may do an excellent job providing a high quality result based on what is asked of it. But the result will only be as good as the quality, clarity, and presentation of the request.

If I hire a home builder to build me a custom home, that builder is going to ask me a thousand questions - questions I had never even thought of. Mythos isn't going to ask all those questions - it's going to make the best choices it can without the consultant's level of interaction. And the buyer will get what they get. Sure, the buyer can then say, "oh, I don't want any hallways - just connected spaces." Then the house gets demolished and rebuilt to the new, clearer spec. Repeat, repeat repeat. Maybe eventually the buyer gets what they really want. More likely they give up before reaching that point, and they go and hire a real builder.

I'll sum it up like this: You can get great results with minimal effort if you don't really care too much about the details. But if you don't care much about the details, then your need probably wasn't very significant.

by michaelteter

6/10/2026 at 8:33:18 AM

I currently see the problem as follows: The knowledge worker like you sees the need for people like themselves to still be hired, and can reasonably argue for it. However, the management dudes and investors do not understand it, and it is difficult to make them understand, when their (short to medium term) profits depend on not understanding it. So whether you feel threatened or not, is just a matter of you feeling bad or not, but doesn't really matter, when it comes to finding a job.

by zelphirkalt

6/9/2026 at 5:56:41 PM

> It worked for nine and a half hours.

> Again, it wasn’t perfect. As an expert, I was able to spot some errors and omissions (some as a result of the design I had asked for) that I had the AI correct

That's the bit that stuck out to me - that's longer than I would expect to work on a problem in a day or even expect to go back & fix the output of something that has a core reward loop of hours.

My customers are currently clamoring to push down my agent response times from 85 seconds down to below the 20s mark.

At the same time, it is very dissonant to see the industry heading towards hour+ long workflows with an agent.

by gopalv

6/9/2026 at 6:00:58 PM

In Claude's defense (and I cannot believe I'm defending it), I know no single dev who could create what it did (Concord), from a 19-page design document, in 9.5 working hours.

We're gonna go back to the days where our bosses ask why we're just sitting around, but instead of saying "compiling," we'll just say, "waiting for Claude."

by matneyx

6/9/2026 at 10:30:01 PM

I tried to read the 'design doc' - its slop full of vague platitudes and impressive sounding but impossible to pin down management speak - in short, it's slop, and I still don't really get what its supposed to do exactly.

It's some prompt engineered AI harness, that guides the AI to create stats after it researches a subject and ingests the data, but I'm not sure what is it that the tool actually does on top of this.

by torginus

6/9/2026 at 7:22:46 PM

This. I get told things like "you can't build all that on your own?" I've had Claude poop out full feature web apps in under 30 minutes, to a spec. Was it perfect? No, but sometimes even in a simple setup phase you can burn 15 minutes to some obscure setup step that's failing. I cannot just code nonstop at 900WPM or whatever ridiculous speed, and poop out an entire full feature web app, with maybe a few bugs here or there. If you can, come show me, I'll gladly have you race against my Claude prompting capabilities.

Will Claude's code be perfect in one shot? Probably not, will it get you 80 to 90% of the way there with your chosen design patterns in under a few hours? Absolutely.

by giancarlostoro

6/9/2026 at 9:42:36 PM

>>If you can, come show me, I'll gladly have you race against my Claude prompting capabilities.

Sounds like we've nearly reached in coding the point where Paul Bunyan [0] has his epic competition with the chainsaw... and loses by 1/4" and history forever changes...

[0]https://www.britannica.com/topic/Paul-Bunyan

by toss1

6/10/2026 at 5:45:26 AM

And honestly, it will get you the rest of the 10-20% with a little bit of yelling at it once it’s done

by dyauspitr

6/9/2026 at 7:39:50 PM

Sadly I didn't get very many answers to my Ask HN, "What are you doing during inference?": https://news.ycombinator.com/item?id=47944917

by petesergeant

6/9/2026 at 7:44:03 PM

I alt-tab to a MMO and farm XP.

by ModernMech

6/9/2026 at 8:24:00 PM

Which one?

by mattbettinson

6/10/2026 at 4:12:36 AM

Drawing.

by magarnicle

6/9/2026 at 7:21:14 PM

> At the same time, it is very dissonant to see the industry heading towards hour+ long workflows with an agent.

At this point, pay me significantly more, and I'll do it.

by giancarlostoro

6/9/2026 at 8:38:28 PM

> pay me significantly more

Ha ha, that's how you negotiate yourself out of a job!

by warkdarrior

6/9/2026 at 10:40:01 PM

Fire me then, I can bring someone else drastically more value with AI tooling.

by giancarlostoro

6/10/2026 at 5:00:04 AM

"I can bring your competitors drastically more value with AI tooling"

by swader999

6/9/2026 at 6:02:49 PM

My Opus 4.8 regularly works for 10+minutes on a single non-trivial coding request.

by PeterStuer

6/9/2026 at 6:52:31 PM

Your Opus 4.8? Is it now usual to refer to LLMs like that?

by ASalazarMX

6/9/2026 at 7:21:45 PM

Isn't it common to refer to all software like that? "Let my look at my JIRA", "I can't find anything using my Outlook's search function", "My Powerpoint is acting up today", "My browser just crashed" are all sentences I might say during a normal work day

by wongarsu

6/9/2026 at 7:27:03 PM

Depends on the demographic I think. And also tells you surprisingly much about how the brain of person uttering it works.

There are people that almost feel physical pain if something is unnecessarily incorrect.

+ That if the mental model of something is accurate, it is actually _more_ work to say something that is incorrect than just saying the correct thing.

by hypfer

6/9/2026 at 7:41:00 PM

In my mental model, "my Outlook" is the outlook instance running on my computer, on my data. My outlook crashed today. Yours might not have crashed. Similarly, my Jira contains tickets about my work, your Jira does not contain those same tickets. That might be technically the same instance on the same SaaS server, but the server I'm routed to accessing my data with my credentials turns it into "my Jira". My Jira is slow. Maybe you are lucky and get routed to a faster server, or your company is self-hosting. Then your Jira might be reasonably fast

by wongarsu

6/9/2026 at 8:01:44 PM

This is completely fine, as those are your own installs, but LLMs can't be owned by the users, your Opus is the same Opus as everyone else's, your only difference is the suscription tier to their API.

If you had your own on-premises LLM, that would indeed be your LLM, and it would make sense to compare it to the on-premises LLMs of other people, as your setup particulars would affect the result.

by ASalazarMX

6/9/2026 at 8:28:14 PM

The copyright to the Outlook binary isn't owned by the users either, even if they're running it on local hardware. The Opus 4.8 weights are (we assume) the same between users, but the conversation/tooling state is not shared between them by default. I prefer to route around this construction myself, since I do think there's some ontological slippery-slope potential, but from a lexical perspective I think “my” is a perfectly defensible abbreviation in context.

by dasyatidprime

6/9/2026 at 8:43:03 PM

> The copyright to the Outlook binary isn't owned by the users either, even if they're running it on local hardware

There was a time where one actually bought software to own it.

This time is.. actually it is right now. Please leave at once.

by hypfer

6/9/2026 at 7:44:21 PM

Hmm, good point. "My outlook" might actually be correct. Depending on if it is a webapp or the real one running on your device that is.

Similiar to "My game just crashed".

Jira otoh is not yours, because it's in the cloud. It might be "my internet connection", "my browser" or "my account" that is having trouble.

___

Hm. "My train got delayed" is interesting in this context. I don't find that offensive. But that also might be because trains don't seek rent the way SaaS does? Not sure.

I guess trains do not hold me hostage. They might just be a container in which someone does that.

Jira, cloud LLM inference or similar otoh..

by hypfer

6/9/2026 at 9:35:48 PM

The "my train" convention is an interesting argument. It's not actually yours, you're buying a train-as-a-service single-use license, and there are tiers to that too.

I guess the main difference is that TAAS has many different trains where the experience varies wildly, so it helps to be specific on which train you're licensing; but LLMs are the same product for everyone, and you can't stay with say, ChatGPT 1.0, you get the same choices as everyone else.

by ASalazarMX

6/9/2026 at 8:56:57 PM

> tells you surprisingly much about how the brain of person uttering it works

That's ridiculous. You wouldn't respond to "I went to visit my doctor yesterday" with "but slavery has been illegal since forever!" Similarly it would be foolish to respond to "where should we meet? my place or yours" with "but we both rent!"

by RugnirViking

6/9/2026 at 7:32:57 PM

better than "The JIRA" , or "The Google" or "The Spotify"

by calvinmorrison

6/10/2026 at 7:30:35 AM

I probably should have used 'Opus 4.8 in my Claude Code configuration'. The model and harnass might be yhe same for everyone, but the .md's, hooks, skills, agents, MCP ... configurations make everyone's setup fairly unique.

by PeterStuer

6/9/2026 at 7:17:20 PM

You don't have your Opus 4.8 ? I got mine yesterday !

by w4yai

6/9/2026 at 9:24:23 PM

I didn't get mine, but I suspect I might be using yours when I use it.

by ASalazarMX

6/9/2026 at 7:31:37 PM

That's pretty tame, if you want to be disturbed check out r/MyBoyfriendIsAI

by giancarlostoro

6/9/2026 at 9:08:53 PM

Or dog lovers. All sorts of licking, anal cleaning... full intimate relationship.

by throw939494555

6/9/2026 at 10:39:28 PM

You what now? lol

by giancarlostoro

6/9/2026 at 6:11:42 PM

Work duration is also not that valuable of a measure, you're usually better off defining the process yourself in code and having that delegate chunks of work to the models. The only real issue there is that it's harder to take advantage of the providers' subscription discounts, but on the other hand it's easier to do your own model routing, and there's no way I've seen for the normal chatbots to maintain coherence on streams of work measured in days and weeks.

by hedgehog

6/9/2026 at 7:28:54 PM

I think we hit the sigmoid back when the QWEN models were released. By properly structuring my project, I can point it at any extension I want and get it going for 30 minutes to extend whatever. It can't effectively do 'god mode' on all the code, but being a mindful observer and code "professional" I don't need more than what a 128GB VRAM needs.

I'm amazed we're so far into SOTA bloat that the chinese will kill once they start etching silicon with these models.

by cyanydeez

6/9/2026 at 7:43:55 PM

I have been using it for less than an hour so take this with a grain of salt of being excited for the new tech.

In a project like mine (https://github.com/tsz-org/tsz) I am constantly frustrated that models were not doing enough research and were not taking into account other situations. Again and again models would produce code that would fix one thing and break 2 other tests that were "unrelated".

With Fable it seems like tasks are taking much longer (I have not seen a pull request from Fable sessions yet) but reading the transcription of those sessions I can see how it is doing the right thing by not leaving any stone unturned.

As the article says, it's hard to communicate this "feeling" about models because it is very project specific but I thought I share

by mohsen1

6/9/2026 at 8:12:01 PM

Does this not indicate that the project might not be structured in an appropriate way that allows incrementally adding features?

by anematode

6/9/2026 at 8:32:35 PM

In general, sooner or later you need to restructure one thing or another when requirements are changing. Good code lets you reason about a refactoring, and experience tells you when it is necessary or appropriate. Coding agents aren’t very good at the latter.

by layer8

6/9/2026 at 8:27:52 PM

the setup is solid. there are thousands of tests and CI won't let things to merge if tests are failing.

But overall, this is pretty normal for compilers to have this sort of "unexpected" tests failing due to some work in an area. It happened to me when I was coding everything manually back in the day too

by mohsen1

6/9/2026 at 9:57:52 PM

> there are thousands of tests and CI won't let things to merge if tests are failing.

That's not what a clean setup means... I mean good separation of concerns, established invariants, etc.

by anematode

6/10/2026 at 7:48:09 AM

A compiler and type checker is very special case where you can fix something in the lexer or parser and break another thing in AST walker etc. tsz is well architected but those things can happen if you're not careful and that's precisely what I meant in my original comment. Fable can think how changing parser can impact checker etc...

by mohsen1

6/9/2026 at 7:48:45 PM

[dead]

by nxmxksisksnssb

6/9/2026 at 7:25:34 PM

What are people working on that they see such a substantial difference between Mythos and Opus? I'd say I'm working with advanced stuff and more than often Deepseek is even more than enough. Why is everybody a genius in here?

by selfawareMammal

6/9/2026 at 8:19:43 PM

Just depends what you are working on. If you are trying to make a video game that's at a level of a decent indie game (think Hades/Baazar/etc), making UI elements/VFX/complex shaders/etc that are organic/interactive/animated that don't feel like a little dogshit vibeslop web-game, then none of the models are even close to good enough to get it done easily. Huge percentage of problems in top 3% games is really hard for any of the models to do with simple prompting.

Personally I don't really care, because I like coding and learning myself and DeepSeek Flash is all I really care about. But it's really easy to have a ton of benchmarks where the top models can't get anywhere close - and I like to test them on these problems to see how good they are getting.

Fable 5 is def a little better than 4.8 btw.

by jenniferhooley

6/9/2026 at 7:31:03 PM

We see the same thing when new laptops are announced and every employee all of a sudden needs to upgrade, despite the fact that 90% of people would be able to make do with a Macbook Neo.

by mervz

6/9/2026 at 9:08:09 PM

> despite the fact that 90% of people would be able to make do with a Macbook Neo.

Myth. Total myth! I recently had to beg for more RAM after continually hitting swap space which causes tools like dictation to stop working, failure to load certain websites without rebooting, and so on. Devs do in fact need powerful machines and the ~$500-1000 an employer saves upfront in machine costs is dwarfed by productivity losses.

Giving your engineering employees new machines in a 2-year cycle that are between the middle and high end is one of the cheapest ROI decisions that a tech org can make.

by Our_Benefactors

6/9/2026 at 9:44:28 PM

Surely devs could just uninstall Slack, and get the same combined RAM & productivity boost?

by oarsinsync

6/10/2026 at 2:06:47 AM

I'm working on my own programming language. I've also been exploring open source projects to contribute to. Maybe something that helps me pivot from hobbyist to professional. If such a thing is even possible in this day and age.

Fable 5 found quite a few issues Opus 4.8 missed on code review, even though the stupid cybersecurity nonsense downgraded it. I can't tell you more, I only get a single session per 5h window on Max 5x. Only ran two sessions so far.

by matheusmoreira

6/9/2026 at 7:39:55 PM

I’ve been working on implementing some common web infra type projects in Rust lately. Basically trying to use a lot of the great primatives in Rust like rustls (modern openSSL) and Tokio (async) to build memory safe or close, nginx drop in replacements.

A small portion of this effort is having a high quality Lua in Rust repo. I’m using mythos to fix some of the performance issues with my Lua interpreter that gpt 5.5/ opus 4.8 had stone walled on.

Not sure if Mythos will be able to crack this but it has been running for a couple hours now with some promising results.

Performance charts linked here if your curious https://github.com/ianm199/lua-rs

by ianm218

6/9/2026 at 10:31:49 PM

What’s wrong with mlua?

by mplanchard

6/9/2026 at 11:05:13 PM

Mlua works for many use cases but is a wrapper around the C code, so you need to bundle C as part of the build. So this is worse for cross compilation and makes it so you can't easily use mlua projects in wasm32-unkown-unknown. An example is that it would be hard to run a game in the browser that exposes Lua scripting with mlua.

The other reason is that because mlua is just a wrapper around the C code, it has unsafe you can't really get around. So for example Lua is used in Redis, which has this critical CVE https://github.com/redis/redis/security/advisories/GHSA-4789... that a memory safe version of Lua wouldn't have to deal with.

Mlua is still fine or even better for many other cases though!

by ianm218

6/9/2026 at 11:21:09 PM

The WASM thing makes sense. Do you need unknown-unknown? Seems like support exists for emscripten and wasi: https://github.com/mlua-rs/mlua/issues/366

It just seems like a lot of hassle to write a lua interpreter, although it would be nice to see a high quality one in Rust :)

Hematita was promising, but looks abandoned.

by mplanchard

6/9/2026 at 11:27:55 PM

Yeah an example is that currently you can't build Bevy games in the browser with scripting in Lua, so I've gotten a little traction there.

And yes it seems like there has been many attempts to get a solid Rust Lua over the years and most never reached parity so hoping some people can find use case for it! This one is at full parity in terms of behavior and performance is getting to within striking distance.

by ianm218

6/9/2026 at 11:35:11 PM

Best of luck! We used mlua at $JOB for scripting support, and it worked great, but we’d have preferred a pure rust solution if one existed with the right performance profile

by mplanchard

6/9/2026 at 9:54:17 PM

I am sure you would not find it hard to exhaust any model, if you kept upping your ask enough times.

On the margins, suppose the prompt is literally: "Build a feature complete, high polish Facebook clone". Facebook is complex but likely not super complicated tech, and still I would assume that (after having burned through a substantial amount of tokens) you would find substantial enough differences in the outcomes between different models on that prompt on various fronts.

The above ask is obviously not useful, but what's preventing you from taking on bigger chunks until you approach the limit? At some point you would hit a boundary, where the diff will be obvious.

by jstummbillig

6/9/2026 at 7:45:17 PM

I had a few of the benchmarks left alone and was working on tech debt knowing that a new model is going to be released soon. For my project (tsz.dev) Opus 4.8 was running in circles without producing results for a while for those tasks

by mohsen1

6/10/2026 at 9:35:19 AM

Probably just a model that was trained on high code bases, tuned to find security breaches and bugs by being "smart" enough to actually test the code by itself / manually going through the app / website feels easy for Fable so Mythos is just a better version.

by dmzxnico

6/9/2026 at 7:24:39 PM

This is what he built:

https://isochronic-passage-chart.netlify.app/

Doesn’t work too well on mobile but looks interesting

by theturtletalks

6/9/2026 at 7:55:42 PM

It is hallucinating many flights in my region, some that never existed (so it is not an outdated data problem).

I also see some logic flaws. It overlooks the option of going to a major hub to access faster aircraft, rather than hopping on local hubs.

Also, immigration and customs are cleared at the first airport you arrive at in the country, not at the last one.

In some countries, you need to clear immigration even while going to a third country, so 1 hour is not enough to do it.

by jampa

6/9/2026 at 7:39:35 PM

It looks interesting but, like a lot of AI, looks correct but is not. Most of northwestern Canada says you can get there by road. If you look at Google Maps, there's no roads there for quite awhile. I see one highway between Inuvik and Tuktoyaktuk but that's about it.

by skipants

6/9/2026 at 8:45:52 PM

Reminds me of a fun story. Some 20 years ago when I moved from Fort Frances to Toronto for college, my high school best friend was also going to college in Toronto, and his dad offered to drive us together in his truck with all our stuff in the back. We were saying our goodbyes and my buddies dad said to my dad "We'll get there a lot faster, I found a shortcut!" My dad, confused says "shortcut? there is no shortcut, just highway 1..." and his dad insists he found an alternative route, much shorter by kms and we'll fly up there 6 hours faster! Get into the truck and he pulls out 5 pages of printed mapquest... I assure you, having done it, Sault Ste. Marie to Sudbury via Elliot Lake on logging roads, may look interesting, but not correct, added a good 8 hours to the trip.

by neom

6/10/2026 at 4:20:48 AM

It put the chart title directly on top of Australia.

Which just about sums up my experience with using LLMs to code, really (though not with these state-of-the-art models, admittedly) - it's amazing what they can do, but left to their own devices they'll make boneheaded decisions.

by rgmerk

6/10/2026 at 8:25:52 AM

I believe thats why they put 'Sydney' as an option at the top to recenter the map.

The real issue with the title is that it doesnt fit in the box!

by alt227

6/10/2026 at 3:46:05 AM

It's fun and it looks good regardless of whether its 100% correct (It would certainly take me more than 9 hours of work to do better than this). Making these bespoke tools possible for most people is a big deal.

by ImaCake

6/10/2026 at 4:54:16 AM

The UI is full of glitches: the legend that's placed right on top of Australia, the title that doesn't fit in the box, the crosshair that doesn't accurate track the cursor, the pixellated fonts along the perimeter, the unreadable colour combinations in the overlay, the rendering glitches along the axes when you flip from tab to tab and so on and so forth.

It's like someone took a beatiful, intricate piece of vintage jewellry and made a slapdash imitation out of cheap plastic.

by aix1

6/10/2026 at 6:06:47 AM

Yep. People are creating garbage with AI that looks passable at first glance, or maybe acceptable if you have no taste. This is the kind of software we can expect to receive in the next few years.

by bschwindHN

6/10/2026 at 9:06:37 AM

The Balatro game that Fable spit out (Flipside) https://play-flipside.netlify.app/ is buggy but fun. Fable also fixed one of my personal pet peeves. Unlike Balatro, it comes with a calculator to preview the score!

by shadytrees

6/9/2026 at 7:57:13 PM

Man, that poem it made is terrible. Like just incredibly bad. Sure it's neat that software can make an incredibly bad poem but there is enough bad poetry in the world that we don't need it.

by neaden

6/9/2026 at 9:38:07 PM

How good can a rhyming poem about a haircut where every word starts with S be?

by Kiro

6/10/2026 at 5:53:02 AM

A whole lot better when written by a human, such as Michael Kandel. This was one of the tests of the electrobard in a story from the Cyberiad ("fables for the cybernetic age"). The key point about Samson was his suicide, which despite the obvious isn't mentioned in the six pages of this rubbish. Perhaps guardrails are throttling this corporate "fable"s ability to comment on the human condition.

The poem Kandel translated from the original Polish was, for artistic reasons, completely different. I will be impressed when machine translation can duplicate that!

by electroweak

6/9/2026 at 8:24:41 PM

I wonder what Vogons would think of it.

by layer8

6/10/2026 at 9:54:37 AM

on the places I've checked, mostly Paris to places in Ireland or Britain, the times are off by an order of magnitude

looks nice but deeply flawed

classic LLM output

by brockVond2021

6/9/2026 at 8:20:48 PM

I am… underwhelmed by the artifacts in the post.

I don’t see why working longer is a pro. The results don’t seem much better than you’d get from putting Opus in a long loop.

by wxw

6/9/2026 at 8:40:56 PM

> The results don’t seem much better than you’d get from putting Opus in a long loop.

Care to share the results you got from Opus working on the same prompt? It should be easy to compare quality.

by warkdarrior

6/10/2026 at 4:16:08 AM

Most depressing thing I've read in weeks, and that's a high bar. Hooray to humanity for creating the thing which has destroyed all the value of of being good at creating things.

by Ameo

6/9/2026 at 7:28:54 PM

What it feels like to work with Fable:

> Switched to Opus 4.8: Fable 5 has safety measures that flag messages on most cybersecurity or biology topics. They may flag safe, normal content as well. These measures let us bring you Mythos-level capability in other areas sooner, and we're working to refine them. Send feedback or learn more.

by thepasch

6/9/2026 at 9:41:18 PM

Same experience here. The parts of my project that actually could have benefited from Fable's code review got this instead.

by matheusmoreira

6/9/2026 at 5:41:59 PM

Mollick runs the Generative AI Lab at Wharton, with all the corporate sponsors.

He is a professor but sadly also an AI shill. He should switch to advertising washing power.

by asdK120

6/9/2026 at 5:45:19 PM

So...no engagement with the substance? Not even to explain why it is that this is not a useful description or test of capabilities? Ok.

by MostlyStable

6/9/2026 at 5:50:34 PM

I would like to see it do something useful, like converting pytorch to golang.

by dthread3

6/9/2026 at 6:12:56 PM

Hot damn - is that the floor of what you consider useful?

by lijok

6/9/2026 at 6:00:30 PM

This newfangled car thing is useless. It can't even properly shoe a horse.

by fdsdfsdfzxczxc

6/9/2026 at 6:47:21 PM

Why not get a plan from Anthropic and get that done yourself? Probably is going to cost you as much as a coffee.

by cadamsdotcom

6/9/2026 at 7:39:00 PM

Ethan is a booster but I wouldn't call him a shill. He cites data and mostly in a fair way, though you could argue the sources he chooses to focus on are biased.

by CuriouslyC

6/9/2026 at 6:08:01 PM

Instead of attacking the author, please respond to the content of the article. That is the HN way, and it leads to more substantive and interesting discussions.

by whyenot

6/10/2026 at 6:12:27 AM

No question the capability jump is real, but in my experience it correlates with shortcut-taking. Fable 5 (and Opus 4.8 before it) hallucinates more than any Claude model I’ve used. The most common failure mode is asking it to modify existing code and watching it skip reading the original file, reconstruct that section from imagination, and then apply edits on top of its own invention, even with full context provided.

Maybe my prompts are too vague, but it’s worth noting that every example in the post is a greenfield build, and vague prompting seems to hold up fine when there are no existing constraints to respect.

by xavierforge

6/9/2026 at 11:51:19 PM

I took a brief look at the code for one of the projects (https://github.com/emollick/concord/) he breathlessly praises and says "a software engineer would iron out the remaining potential bugs that I could not find quickly". The code looks like an unmaintainable mess.

Other commenters have pointed out that his isochrone map contains a lot of nonsense as well.

So the most charitable interpretation here is that this is a case of Gell-Mann amnesia.

by SupremumLimit

6/9/2026 at 8:35:29 PM

The snake game is legit very fun. Once I got the ability to pick up the apples and plant apple trees, I was sold.

by mjamesaustin

6/9/2026 at 8:04:57 PM

Isn't it weird that we started to gauge the quality of a model by checking the vibe of the vibe coding?

by mawadev

6/10/2026 at 6:29:09 AM

You can see this all over the place. Under the Fable post in HN, you have simonw talking about the “feel” of working with Fable and how much better it is. If I believed in conspiracies, I’d have said it’s all orchestrated marketing…

by geraneum

6/9/2026 at 6:21:24 PM

would it be possible for mythos to make the space bar scroll the pages on your website properly?

by recursivedoubts

6/9/2026 at 7:18:08 PM

Seems to be hijacked the video of some game they generated. :(

by mulr00ney

6/9/2026 at 9:03:31 PM

If you delete the video from the DOM, then click back into the content area, it reattaches the video lol.

by albedoa

6/10/2026 at 4:00:51 AM

> It also created a 10-page epic rhyming poem about a haircut where every word starts with the letter s

Wow

by philipswood

6/9/2026 at 8:24:15 PM

Nice, but I'm really curious about how many tokens have been used.

There is only one hint: 475k tokens in the screenshot when OP asked the model to fix some behaviour, but it would be fascinating to know the total tokens amount.

by vb-8448

6/9/2026 at 5:48:02 PM

I think Qwen 3.7-Plus is better at reasoning than Mythos, and I've used both for quite a while.

by 382hi

6/9/2026 at 7:32:42 PM

Would love to see samples of the kinds of prompts you use with both. I sometimes wonder if the specific wording is the secret sauce, I have very few issues with Opus / Claude, but when I try premier GPT models, I get weird output from what I've grown to expect with Claude.

by giancarlostoro

6/9/2026 at 7:46:43 PM

> This is a map that shows the distance you can travel in a given length of time, and the first one was created in 1881 showing travel times from London.

The first item on the article, the first thing it showed, was wrong though.

It is 100% faster to go from London to New York in 1881 than Volgagrad. Or any of the Russian hinterland colored green or Turkey or Egypt.

by Aperocky

6/9/2026 at 8:08:22 PM

> faster to go from London to New York in 1881 than Volgagrad

the map is for 2026, yeah?

by patcon

6/9/2026 at 11:36:41 PM

yeah the original map was not for this purpose. Though I would say there are heavy assumption made for 2026 too, namely the flights are available immediately upon demand.

by Aperocky

6/9/2026 at 10:11:23 PM

Loved the article!

And I'm excited to try it, but also have a fear that I will like it too much and then won't have access to it in 2 weeks... But maybe I will and maybe it will be worth it and I'll just pay a bunch of extra for it and it'll be great!

I think the article could be improved by actually sharing more feelings. I clicked on the article for feelings but I didn't see that many feelings described.

by ElijahLynn

6/9/2026 at 9:51:11 PM

Who can afford to use this damn thing though? They're pricing everyone out of the market with stuff like this.

by ComplexSystems

6/9/2026 at 5:39:49 PM

I just can't stand this type of fawning language.

by root_axis

6/10/2026 at 8:52:41 AM

Given that token counts are easily available not providing how much any of his examples cost is lunacy.

by philipwhiuk

6/9/2026 at 8:12:01 PM

>Ethan Mollick

Just an FYI this guy is an AI hype-beast. Some of his tweets are truly out there.

by catigula

6/9/2026 at 8:30:59 PM

Huge fanboy for sure

by dogmayor

6/9/2026 at 8:35:06 PM

> it is indicative of AI solving a hard problem involving research, math, visual development, taste, judgement, complex coding, and more.

Is it a hard problem or is it just labor intensive?

by steve1977

6/9/2026 at 8:36:28 PM

Depends on the skill of the person working on it.

by warkdarrior

6/9/2026 at 10:04:52 PM

> The work has shifted from process to outcome. I no longer steer; I commission.

by ElijahLynn

6/9/2026 at 8:32:24 PM

My wife likes to say "feelings aren't facts"

by PaulHoule

6/9/2026 at 5:53:44 PM

More Mythos Marketing.

by the_doctah

6/9/2026 at 7:22:08 PM

The mythos of Mythos is marketing.

by boringg

6/9/2026 at 7:56:03 PM

What it feels like to work with Mythos? Feels like am poor

by ThejaCH

6/9/2026 at 8:38:39 PM

I'm using Fable this afternoon and it's definitely a step up from Opus 4.8, finding and fixing things Opus 4.8 was blind to even perceiving. The next 13 days are going to be fun IMO. And Opus 4.8 was less annoying than Opus 4.7 FWIW.

Edit: A couple hours in and I just got my first gaslighting attempt from the model. Good times!

by LogicFailsMe

6/9/2026 at 7:44:02 PM

Was the condition of being granted early access to this castrated model writing a post praising it?

by zb3

6/9/2026 at 7:40:43 PM

> First, how good is Fable? In experiment after experiment I conducted, it outperformed basically every other public model I have used by a considerable margin.

What makes me excited is that GPT 5.6 (its actually GPT 6) is going to be crazy

by zuzululu

6/9/2026 at 8:11:36 PM

>What it feels like to work with Mythos >Looks Inside >So I did this with fable...

What?

by younglunaman

6/9/2026 at 8:43:07 PM

Fable is Mythos with extra guardrails, so the analysis holds.

by warkdarrior

6/10/2026 at 6:38:32 AM

Considering all the initial Mythos hype (before they released Fable) was for things that Mythos explicitly can't do, no, not really.

by Chu4eeno

6/9/2026 at 7:56:50 PM

Reading it, I can't help but feel he's being paid to write this. Or maybe he hopes to be paid. The language he uses makes him sound like he's fawning over the lost days of his childhood. Pardon me for being skeptical, but a trillion dollar company running a net-loss is hoping to IPO, and needs to sway public opinion by any means necessary. I would imagine that no dirty marketing scheme is off of the table, even from the self-proclaimed "good guys".

by honeycrispy

6/10/2026 at 9:23:17 AM

[flagged]

by Andy_Donner

6/10/2026 at 3:56:12 AM

[flagged]

by andrewvu0203

6/10/2026 at 7:09:35 AM

[flagged]

by aryehof

6/10/2026 at 5:49:35 AM

[dead]

by ath3nd

6/9/2026 at 5:46:41 PM

[flagged]

by et-al

6/9/2026 at 6:10:43 PM

It is not a sponsored article and he writes one of these every time a new model releases. Why would a professor at Wharton need to write sponsored Substack articles.

by astrange

6/9/2026 at 6:01:48 PM

"I don't care who the IRS sends I am not paying taxes!"

by 0x1ceb00da

6/10/2026 at 1:24:00 AM

So, Ethan Mollick has just broke an NDA he signed. Typical. Out of everyone participating in Project Glasswing it was, of course, the Uni to f*k it up.

by pbgcp2026

6/10/2026 at 3:25:00 AM

The model is public and none of the inputs/outputs contained biosecurity or cybersecurity prompts.

You can do all of this (and more) on Claude Fable 5, in-fact Fable 5 outperforms Mythos in most tasks (where the guardrails don't kick it at least).

by HDBaseT