Installation

Installation

SkillFishOS 26.06 "Aetherium" ships as three installable editions, each ~6.2 GB, built with penguins-eggs and verified to boot the matching kernel. The live system boots in English; you choose your language during install.

Editions

Edition	Kernel	For
BC-250	7.2.0-skillfishos (-march=znver2)	The AMD BC-250 board (recommended)
Generic	7.2.0-skillfishos-generic (-march=x86-64)	Ordinary PCs & virtual machines
Slim	7.2.0-skillfishos-slim	BC-250 only, ultra-lean module set

Download from SourceForge.

Write the ISO

Flash to an 8 GB+ USB stick with your tool of choice:

sudo dd if=SkillFishOS-26.06-Aetherium-BC250-amd64.iso of=/dev/sdX bs=4M status=progress oflag=sync

(or balenaEtcher / Ventoy / Rufus). Replace /dev/sdX with your USB device — double-check it.

Secure Boot

Turn Secure Boot off before you write the stick. SkillFishOS builds its own kernel, and a machine with Secure Boot enabled refuses to start code it has no signature for: GRUB comes up, hands over, and nothing happens. The setting is in your firmware setup, usually under Security or Boot.

Once installed, you can turn it back on. The kernel we publish is signed with a SkillFishOS key, and skillfish-secureboot --registra enrols that key in your firmware — once, with a confirmation on the firmware's own blue screen, so the decision stays yours and in front of the machine. Booting the installer from a stick will always need Secure Boot off, because a key cannot be enrolled before the machine has run once.

See Troubleshooting#the-machine-stops-right-after-grub-secure-boot if you are already stuck.

Install

1. Boot the USB stick (the live desktop comes up in English).
2. Launch Install SkillFishOS (Calamares).
3. Pick your language, keyboard, timezone, disk and user.
4. On the BC-250, install to the internal NVMe/eMMC; the installer shows the release name "SkillFishOS 26.06 Aetherium".
5. Reboot and remove the stick.

First boot

• A first-boot service creates the Btrfs .snapshots subvolume and configures Snapper + grub-btrfs, so pre/post-update rollbacks appear in the GRUB menu after your first apt run.
• The signed APT repo is already configured — apt and the SkillFishOS Hub keep the kernel and every native app up to date.
• The SkillFishOS Tuner ships the safe Stock profile; opt into more performance whenever you like.

BIOS / UMA VRAM note

The amount of memory reserved for the GPU (UMA VRAM) lives in the BIOS CMOS. The Tuner can change it for you (it writes the CMOS and asks for a reboot). See Memory VRAM and GTT.

Updating

sudo apt update && sudo apt full-upgrade

…or use the SkillFishOS Hub / KDE Discover. A Btrfs snapshot is taken automatically before and after every update — if anything breaks, roll back from the GRUB menu. See APT Repository.