John Carmack's arguments against building a custom XR OS at Meta • Hacker News Board

Re: John Carmack's arguments against building a custom XR OS at Meta

#361

Post by monkeyelite » Sat, Aug 30, 2025, 6:14 AM UTC

influx wrote: post #227

jamra wrote: post #202

Earlier quoted context omitted.

I followed his posts internally before he left. He was strict about resource waste. Hand tracking would break constantly and he brought metrics to his posts. His whole point was that Apple has hardware nailed down and it’ll be efficient software that will be the differentiator. The bloat at Meta was the result of empire building.

I followed his posts internally too. It's amazing how many people were arguing against fucking John Carmack. What a waste of talent.

I disagree that you should just defer - but it’s sad that politics was obviously consuming and inhibiting his ability to help the product.

Re: John Carmack's arguments against building a custom XR OS at Meta

#362

Post by monkeyelite » Sat, Aug 30, 2025, 6:17 AM UTC

sesm wrote: post #160

gmueckl wrote: post #130

Earlier quoted context omitted.

It matters who you communicate concerns to. Something as fundamental as "I think that your team shouldn't even exist" should go to the team leads and their managers exclusively at first. Writing that to the entire affected team is counterproductive in any organization because it unnecessarily raises anxiety and reduces team productivity and focus. Comments like this from influential people can have big mental and phy…

This entire situation looks very suspicious. Was Carmack even responsible for triaging research projects and allocating resources for them? If yes, then he should have fought that battle earlier. If no, then the best he could do is to refuse to use that OS in projects he controls.

That’s not how big companies work.

Re: John Carmack's arguments against building a custom XR OS at Meta

#363

Post by pjjpo » Sat, Aug 30, 2025, 6:17 AM UTC

throwaway2037 wrote: post #345

dist1ll wrote: post #200

Earlier quoted context omitted.

Intel still does it. As far as I can see they're the only player in town that provide open, detailed documentation for their high-speed NICs [0]. You can actually write a driver for their 100Gb cards from scratch using their datasheet. Most other vendors would either (1) ignore you, (2) make you sign an NDA or (3) refer you to their poorly documented Linux/BSD driver. Not sure what the situation is for other hardware…

Wow... that PDF is 2,750 pages! There must be an army of technical writers behind it. That is an incredible technical achievement. Real question: Why do you think Intel does this? Does it guarantee a very strong foothold into data center NICs? I am sure competitors would argue two different angles: (1) this PDF shares too much info; some should be hidden behind an NDA, (2) it's too hard to write (and maintain) this P…

In terms of (2), I wonder if it's even possible to write a driver without such a document. In the end, the vendor is on the foot for the driver for major platforms (let's assume Linux) - if they can write a Linux driver without a similar spec to this doc, then the doc probably doesn't need to exist since the business wins from hobbyist drivers will be low. If they can't though, then it's just a matter of formatting an internal document for public consumption - the doc itself has to be maintained anyways so the cost seems lower and maybe reasonable. I have a feeling the doc is necessary but I am not specialized in the field.

Assumptions, fair or not, about (1) seems more likely somehow.

Re: John Carmack's arguments against building a custom XR OS at Meta

#364

Post by monkeyelite » Sat, Aug 30, 2025, 6:20 AM UTC

os2warpman wrote: post #277

SgtBastard wrote: post #152

Earlier quoted context omitted.

Technically you are correct but the commenter you’re responding to means that with the amount of Western Governments spend on MS products and services, the are a d facto (if not de jure) state backed enterprise.

US government spending is (for now) easy to track, and you can get totals for spending by corporate entity. In total across the entire US federal government, $518.8 million was paid to Microsoft for products and services in 2024. That is approximately 0.21% of their total annual revenue. I assert that the threshold for "state sponsored" is well in excess of 0.21% of annual revenue. Federal Spending: https://www.usasp…

If you look at Ford and Intel you would find similar numbers - but they are clearly quasi state entities.

Re: John Carmack's arguments against building a custom XR OS at Meta

#365

Post by newlisp » Sat, Aug 30, 2025, 6:20 AM UTC

pipeline_peak wrote: post #66

Jonathan Blow is the world’s most successful hobbyist programmer. His whole thing is doing projects from scratch. Every game he made could be done in Unity with far less effort. Most opinions of this man exists in a vacuum space isolated from the real world software industry. Building an OS from scratch is one of those examples. It’s never seems like there’s a significant reason behind them other than………”I made dat :…

If he is selling his games, is he a hobbyist?

Re: John Carmack's arguments against building a custom XR OS at Meta

#366

Post by pjmlp » Sat, Aug 30, 2025, 6:22 AM UTC

1718627440 wrote: post #177

BiteCode_dev wrote: post #84

Earlier quoted context omitted.

Having worked in the valley, I've seen what critical feedback meant in many companies there, and it removes all usefulness of the info because there is a ceiling of what is socially acceptable to say; therefore, you can't know how bad or urgent things are. Everything is ASAP. They are super excited about everything. And nothing you do is wrong, it just could be improved or they like it but don't love it. You don't kn…

> In Germany, you can't even legally say somebody did a bad job at your company in a recommendation letter. Companies created a whole subtext to workaround that, it's crazy. I don't think it's just about legality. Whether the recommendation letter is included in the application is at the distinction of the applicant. When you want it to reach the next company, you must write is so, that the former employee considers…

It is, as Portuguese it surprised me a lot.

First of all, in southern countries we hardly do recommendation letters, if we do they usually ended up being written by ourselves and if the company agrees with the content, it gets signed.

Exactly because of this, you are supposed to give referrals that then talk whatever they feel like about the experience working with you was all about.

Having a whole legal process for recommendation letters, that have created a whole industry of hidden language that looks good on the surface but tells exactly otherwise, was a surprise to me.

https://www.betriebsrat.de/news/arbeitnehmer/achtung-arbeits...

https://www.zeugnisprofi.com/wissen/arbeitszeugnis-geheimcod...

https://www.orizon.de/de/karriereratgeber/arbeitszeugnis-ver...

Just some examples, there are lawyers that analyse recommendation letters as one of their services.

Re: John Carmack's arguments against building a custom XR OS at Meta

#367

Post by monkeyelite » Sat, Aug 30, 2025, 6:22 AM UTC

scared_together wrote: post #7

What if instead of writing the entire OS, a company were to pick up an existing “hobby” OS and refine it? For example any of the systems listed in Carmack’s post. Or perhaps Serenity OS, RedoxOS, etc.

How is that different than what they did? Meta stuff is on Linux. PlayStation and Nintendo on bsd, etc.

If you mean exotic ones then the answer is the parts that are written are the easy parts and getting support for hardware and software is hard.

Re: John Carmack's arguments against building a custom XR OS at Meta

#368

Post by monkeyelite » Sat, Aug 30, 2025, 6:23 AM UTC

numpad0 wrote: post #101

Is the difficulty in theoretical complexity of operating systems, or in project scoping/scope creep? It's probably not that hard to write bare metal code for a modern CPU that runs and crashes. It's obviously insurmountably hard to compete with Android in features with scratch built bare metal code. An "OS" can be anything between the two. But it's very easy to imagine an "XR OS" project snowballing quickly into the…

the thread lists examples like 3rd party software

Re: John Carmack's arguments against building a custom XR OS at Meta

#369

Post by pjmlp » Sat, Aug 30, 2025, 6:24 AM UTC

xantronix wrote: post #89

webdevver wrote: post #30

tbh linux has quite a bit of cruft in it these days at the syscall and interface layer. if youre apple, it does make sense to do stuff from scratch. i think in a way, software guys wind up building their own prisons. an api is created to solve problem X given world Y, but world Y+1 has a different set of problems - problems that may no longer be adequately addressed given the api invented for X. people talk about "re…

Apple doesn't do a lot of baremetal development from scratch that I'm aware of. The Lightning to HDMI dongle bootstraps an XNU kernel with an AirPlay decoder into 256MB RAM, for instance.

Boot loader firmware, initially done in a Safe C dialect, nowadays one of the reasons Embedded Swift came to be.

Re: John Carmack's arguments against building a custom XR OS at Meta

#370

Post by Joker_vD » Sat, Aug 30, 2025, 6:35 AM UTC

jnwatson wrote: post #23

I've written a lot of low level software, BSPs, and most of an OS, and the main reason to not write your own OS these days is silicon vendors. Back in the day, they would provide you a spec detailed enough that you could feasibly write your own drivers. These days, you get a medium-level description and a Linux driver of questionable quality. Part of this is just laziness, but mostly this is a function of complexity.…

> Modern hardware is just so complicated it would take a long time to completely document, and even longer to write a driver for.

You know, one'd think that having a complex hardware should make writing a driver easier because the hardware is able to take care of itself just fine, and provide a reasonable interface, as opposed to devices of the yore which you had to babysit, wasting your main CPU's time, and doing silly stuff like sending them two identical initialization commands with 30 to 50 microseconds delay between or whatever.