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

Which makes sense when you are one of 3 developers at ID software. There's absolutely no room for waste.

This is Meta. Let the kids build their operating system ffs. Is he now more concerned with protecting shareholder value? Who cares.

>Is he now more concerned with protecting shareholder value? Who cares.

It doesn't sound like he's concerned with waste. It sounds like it's a typical Carmack argument - distilled and hyper logical, and his conclusion is more to do with the pointlessness of it. He actually concedes the point that the project may have been highly efficient (which it may or may not have been, he was steelmanning).

His main points seemed to be:

If every cycle matters and efficiency is paramount, just make the project monolithic C++ code. If every cycle matters, that is somewhat incompatible with general purpose OSs, and if it doesn't, the existing landscape is more than good enough. Presumably, he's calling out the absurdity of counter-arguments which are being unrealistic about the objectives of creating a new general purpose OS, while also focusing on extreme efficiency. He states that the requirements to fully achieve these objectives would require a "monastic coding enclave" like Plan 9 OS, and it wasn't realistic even with the high talent in Meta.

And that plays into the second point, which seems to essentially be "new OSs aren't a draw for developers, they are a burden". This is painfully obvious when looking at the history of OSs and software, and it's the obvious reason why "let the kids build their operating system ffs" should result in a reflexive "noooo..." from the greybeards. The deeper point though is that if A. is achieved, the B. Burden on devs will be even more onerous. Therefore unless the entire project is committed to truly moving crowds to new paradigms (good luck, literally billions have been lost here), just use the proven, faily high performance options that have widespread support.

The conclusion is "on balance, it's a bad idea." He's arguing it sharply (although I understand a Carmack steelman is intimidating to attack), but in essence it's a fairly banal and conservative conclusion, backed with strong precedent.

Meta's AR/VR division has burned a huge amount of money and years of time, with relatively little to show for it. Now it seems to be on the verge of being cancelled or slashed back, and in response people are saying that this proves VR, something Carmack champions, is commercially untenable or even that Carmack himself is partly responsible for the failed initiative. I don't even entirely agree with him on the question of whether anyone should try developing a new OS, but he's been proven absolutely right that there was no room for him to be that complacent about the use of Meta's resources.

There were almost no kids on the XROS team. The bulk of the team were E6s with graying hairs, multiple kids, and very impressive history of work on other well-known operating systems -- and most of them wrote a lot of code. This was the senior-est team I ever was a member of. Also, the most enjoyable interview process I've ever been through, no bullshit whatsoever and a rare case that I actually had to implement the exact thing that I was asked about during the interview (took me 3 weeks compared to 20 minutes during the loop, go figure).

XROS was an org that hired for specific specialist positions (as opposed to the usual "get hired into FB, go through the bootcamp, and find your place within the company"). At one point we got two separate requests from the recruiting execs: - Your tech screen pass rate is way too low compared to other teams at FB. Please consider making your tech screen easier to expand the pool of candidates. - Your interview-to-offer rate is way too low compared to other teams at FB. Please consider making your tech screen more difficult to reduce time that engineers spend on interviewing and writing feedback.

Anyway, IMO it was a very strong team in a very wrong environment. Most of the folks on the team hated the Facebook culture, despised the PSC process (despite having no problems with delivering impact in a greenfield project), had very little respect for non-technical managers coming from FB proper (the XROS team saw themselves as part of Oculus), and the majority I believe fled to other companies as soon as the project was scrapped. The pay was good however, and the work was very interesting. My overall impression was that most people on the team saw XROS as a journey, not a destination, and it was one of the reasons why it was destined to never ship.

That’s what I’m saying. It sounds like a dream job. Like you said it’s a journey not a destination, but it’s also a journey on one of the wealthiest companies in the worlds dime, so it’s kinda lame when someone calls it out for being suboptimal. That’s why I said who cares. It’s not going to hurt meta in the long run.

I believe the suboptimality concern was more about time to market and innovation velocity, and less about money. At the time FB felt a real sense of urgency given the anticipated AR/VR explosion (in a good sense) and presence of competitors in the space, both real and imaginary.

No, no. If you want your VR apps running in two years on something that looks like an OS, just build an app that runs on an existing one.

If you want to be the dominant player in the market in 10-15 years, build the OS and keep funding it.

I chatted with someone on the language side of the project (I believe the same project) and it was fascinating how ambitious the concept was. I do wish it was finished or open sourced though

It did hurt Meta. No one has infinite resources even if it seems that way to us.

This is how megacorps die. You’re describing Intel-level complacency.

> This is Meta. Let the kids build their operating system ffs.

the problem was, it was holding back products. Because if youre going to make your own OS, it changes what chips you put in. If you don't know what chipset you're going to have, you don;t know what your pixel budget is, you can't plan features.

It takes about 2 years to get hardware out the door, and another 1.5 years to iron out the bugs and get a "finished" product.

Professional engineers cannot be made immune to criticism.

AR/VR was always a side project for Zuck (like the Aquila airplane or the Libra cryptocurrency or AGI) that he works on because he's bored. It was pretty clear from the product's popularity and Metaverse experience that it didn't have any legs. Carmack had little to do with that one way or the other, and the Apple Vision pro shows that it's not an execution or quality issue, it's product-market fit.

I just can't believe that an OS needs to be forked off for such a workload

iPhones and Macs share a kernel and a large portion of user space and syscalls, right?

If the GPL is a problem just fork some BSD like the PS3 did, and pretend you're maintaining code that you already spent five years on

I know you need low latency for XR + VR + AR - everyone needs low latency for everything. So they could build on whatever has been done for audio and networking and Android touch screens that all want low latency too

I'm speaking foolishly from outside but making "an OS for" something is more commonly marketing speak than a good idea. Like this fucking "OS for cities" and "OS for work" stuff. That's an OS the way a cookie recipe is an OS for a fucking oven. The casual insistence on misunderstanding important things really gets my goats

Side project that they renamed entire company after

Yep, and the common mantra is that "ambitious" and "v1" shall never occur together in the same sentence.