To build a new OS, or not to build a new OS?

There's a fascinating debate in the software world about whether it still makes sense to create a new general-purpose operating system from scratch.

The Pragmatic View

On one side, you have figures like John Carmack. In a recent discussion on X, he argued that building a new OS is often impractical. The cost, short lifespan, and developer burden rarely justify the effort, a lesson he learned from opposing Meta's custom XR OS.

The Idealistic View

On the other side is the spirit of the ultimate craftsman. This is captured perfectly in a joke by DHH during this presentation:

"People who are really serious about software should make their own operating system."

He's riffing on a famous quote by Alan Kay about hardware, but the message is clear: the ultimate challenge for a software purist is to build the whole stack.

A Middle Ground: Omarchy

Interestingly, DHH's own work offers a third path. He hasn't built an entirely new OS. Instead, he created Omarchy, an "opinionated Arch + Hyprland Setup."

Omarchy is a customized version of Arch Linux, tailored for a keyboard-first, developer-focused workflow. It's a practical compromise: leveraging the stable foundation of Linux while building a bespoke user experience on top. It avoids reinventing the kernel but still achieves the goal of a perfectly tailored environment.

The End of the OS Wars?

This conversation raises a bigger question: have we reached the end of the line for general-purpose operating systems? For decades, the landscape has been dominated by two major families: Unix-likes (now primarily Linux and macOS) and Windows.

The sheer scale of these ecosystems is staggering. They have decades of development, vast hardware support, and millions of applications. For any newcomer to compete, they wouldn't just need a better kernel; they'd need to replicate this entire universe. The network effect is so strong that it creates an almost insurmountable barrier to entry.

I'm with Carmack on this one. The practical challenges of building a new OS are immense, and the likelihood of widespread adoption is slim. The only way I see this changing is if some hardware company decides to break the mold for new hardware, using a modern language (Rust?) and bridging the gap with existing ecosystems by using AI. But, even then, the odds are against them.