Rethinking microkernels: Towards a modern general-purpose OS
In 2024, I started creating a brand new microkernel-based operating system called Starina. It aims to be a modern general-purpose OS that is performant, secure, and developer-friendly, for production use. In other words, the third option in open-source general-purpose OS world besides Linux and BSD family.
Starina is still in the early stage of development, but it's already taking good shape - starina.dev is served by instantly-booted Starina VMs running on Linux hypervisor (QEMU) on Raspberry Pi! Visit the website to say hi to Starina :)
Microkernel is a kernel design where most of OS components (file systems, TCP/IP, device drivers, ...) are implemented as user-space processes, and the kernel provides only minimalistic features. It enables better fault isolation, better security, and better maintainability. All things aside, microkernel design is beautiful, cool, and elegant.
However, we don't see microkernel-based OS in general-purpose use today. Hybrid kernels like XNU (macOS) are the most microkernel-ish OS in the market. This is because, according to a folklore, microkernels are slow due to IPC overhead.
