Default Kernel

The P03 Kernel

A Linux kernel obsessively tailored for efficiency and desktop interactivity, built on Fedora's base with the best patches from the performance-kernel community.

P03 is developed independently by CatPieLeaf and ships as RakuOS's default kernel — but it's a standalone project. You don't need to run RakuOS to use it; it's just a first-class citizen here.

Highlights

Automatic Secure Boot Signing

Local key generation and signing happen automatically at build/install time — no trusting distributed keys, no hand-rolled signing scripts.

Tailored, Not Blind Performance

Every patch is chosen for real efficiency and responsiveness gains, not benchmark chasing — tuned for how the kernel actually feels to use.

Firelzrd's Patch Set

Includes most of Firelzrd's work: LRU-Marie, BORE, ADIOS, PoC-Selector, Cambyses, Nap CPUIdle, ZRAM-IR, and more.

Handheld & Surface Support

First-class support for handhelds like the ROG Ally and Steam Deck, plus Microsoft Surface devices.

Modular Spec-File Build

Fully modular RPM spec build using patches on top of Fedora Koji SRPMs as the base source — an approach inspired by the TKG kernel.

Unfair By Design

Desktop-centric and interactivity-first, on purpose. (Future EL builds flip this: fair scheduling, server-centric.)

Best of Every Kernel

Pulls proven patches from XanMod, CachyOS, Clear Linux, TKG, and others — whichever approach works best.

dmemcg-booster

Free VRAM savings on AMD graphics via dmemcg-booster support.

AppArmor Support

Built with AppArmor support for systems that want mandatory access control without SELinux.

Building & Configuration

P03 is built from a modular RPM spec file, using Fedora's Koji SRPMs as the base source and layering patches on top — the same approach popularized by the TKG kernel. Expect roughly 1-2 hours to build and about 10 GB of free disk space, with an optional interactive xconfig step and extensive spec-file toggles for picking exactly which patches and options you want.

Pre-built packages are available via COPR for Fedora Workstation and Silverblue, independent of RakuOS.

Full source, build instructions & COPR repo →