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

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521 points OlympicMarmoto | 1 comments | 29 Aug 25 16:45 UTC | HN request time: 0.242s | source
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jnwatson ◴[29 Aug 25 17:46 UTC] No.45067216[source]▶
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.

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bbarnett ◴[29 Aug 25 21:03 UTC] No.45069349[source]▶
Modern hardware is just so complicated it would take a long time to completely document, and even longer to write a driver for.

That's what's claimed. That's what people say, yet it's just an excuse. I've heard the same sort of excuse people have, after they write a massive codebase, then say "Oops, sorry, didn't get around to documenting it".

And no, hardware is not more difficult than software to document.

If the system is complex, there's more need to document, just as with a huge codebase. On their end, they have new employees to train up, and they have to manage testing. So any excuse that silicon vendors have to deal with such immense complexity? My violin plays for them.

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makeitdouble ◴[29 Aug 25 22:57 UTC] No.45070341[source]▶
> "Oops, sorry, didn't get around to documenting it".

That's obviously the wrong message. They should say "Go ask the engineering VP to get us off any other projects for another cycle while we're writing 'satisfying' documentation".

Extensive documentation comes at a price few companies are willing to pay (and that's not just a matter of resources. Look at Apple's documentation)

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1. PeterStuer ◴[30 Aug 25 07:12 UTC] No.45072560[source]▶
With documentation one of the major hurdles is the maintainance. It is caring for a set of documents, created by people with different specializations, that describe the artefact from specific perspectives, but need to be kept in sync with the active creation and evolution of the artefact itself.

This is not impossible, but the effort and costs required are substantial and often lose out on a priority basis to just fixing or improving the product itself.