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

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 "rewrite everything in rust" - I say, why stop there? lets go down to the metal. make every byte, every instruction, every syscall a commodity. imagine if we could go all the way back to bare metal programming, simply by virtue of the LLM auto-coding the bootloader, scheduler, process manager, all in-situ.

the software world is full of circularities like that. we went from Mainframe -> local -> mainframe, why not baremetal -> hosted -> baremetal?

You can still do “unsafe” stuff in rust, and people do. It’s perfectly possible to write safe C and C++ these days. And you don’t have to deal with a borrow checker, and a very small pool of developers available to hire.