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

I think people have forgotten about Google Fuchsia which I guess is a good sign for a new OS. They’ve done quite well in deploying it seamlessly to their consumer devices.

I thought they rolled back all of those efforts. What devices shipping today come with Fuchsia installed?

The reviews I've seen of its stability and usefulness have not been good.

Isn't that somewhat debatable? Originally they were aiming at much more (chromebook OS for example) but seems like they settled for Google Home only as their scope.

Still a very interesting project, but that feels like a similar story, for limited use cases (a smart thermostat/speaker with specific hardware) it works, but for wider use cases with heterogeneus hardware and complex interfaces (actual screen, peripherals) it didn't work.

Google Nest Hub

According to Wikipedia, looks like only the Nest Nub.

Yup it’s because they had to rewrite the drivers I presume. Always going to be the biggest issue with any new OS.

That was also frustrating in that sel4 was right there. Why not invest efforts in the existing thing?

Fun rumor: Google shut down the AR effort and transferred the team to project Fuchsia as a way to retain highly skilled employees. So essentially they didn’t have any real technical needs for a new OS.

It was so good Google cancelled plans to use it in meaningful products and instead delegated it to the bottom shelf products.

I think some of the Nest audio devices now run it as well.

"Quite well" by what metric? It shipped on one device. That's pretty much the lowest bar you can imagine! Did it provide any tangible benefit to anyone? Let alone a benefit commensurate with the enormous cost of developing it and continuing to maintain it?

I think it was insane to start a new OS effort written in C/C++. We have plenty of OSes written in C/C++! We know how that story ends. If you're going to spend the effort, at least try a new language that could enable a better security model.

Fuchsia is pretty much a dead product at this point. For things like Phones and Laptops google is using only Android going forward.

XROS was a Fuschia fork, actually.

The microkernel core isn't the buggy/hard part; Fuscia's got a similar microkernel that also works great. It's everything else that's hard.

While I agree with the sentiment given my bias towards safe systems languages, Genode OS is pretty much mostly C++, although they added some Ada/SPARK as well, which is relatively recent research OS.