Selene OS

Modern installer built in .NET 10 – install Ubuntu 26.04 LTS directly from Windows, no USB stick required

In Development

Selene OS is a modern installer built in .NET 10: Ubuntu 26.04 LTS gets installed from within Windows – no USB stick needed – right next to Windows. In the wizard you choose the desktop (GNOME, KDE, …), user, root account, language, disk space and bootloader behavior; then a single reboot is all it takes.

No USB Stick Dual Boot Desktop Choice Secure Boot

One tool, one download, one reboot – Ubuntu straight from Windows, no USB stick needed

Core Features

Install from Windows

Selene OS runs as a single .exe on Windows, sets up partitions and the bootloader – one reboot is all it takes

Desktop Choice

GNOME, KDE Plasma and other desktops selectable directly in the wizard – one ISO for all desktops

Dedicated ext4 Partition

C: is shrunk and Selene OS gets a real ext4 partition – a proper installation instead of a risky loop file on NTFS

UEFI + Secure Boot

Signed boot chain with shim + GRUB (Microsoft/Canonical) – Secure Boot stays enabled, GRUB shows Ubuntu and Windows

USB Installation Stick

Alternatively Selene OS creates a pre-configured USB stick that installs automatically on any UEFI PC – reusable

Bootloader Management

Switch boot order, “Reboot into Ubuntu” and boot menu repair right inside the tool

Bootloader Concept

Installer Start (BootNext): One-time UEFI boot entry starts shim → GRUB → Selene OS menu → autoinstall (subiquity/curtin)
Installed System: UEFI → shim → GRUB menu with Ubuntu and Windows – Windows entry is created deterministically via ESP UUID
Failsafe: BootNext instead of BootOrder: if installation fails, the next boot automatically returns to Windows
Repair: If a Windows update puts the Windows Boot Manager first again, Selene OS restores the Ubuntu entry
Windows Protection: BitLocker is suspended for 2 reboots before restarting and fast startup is disabled – no data at risk

Two Installation Paths

Path 1: Install from Windows

Alongside Windows (shrink C:), whole disk or free space – targets detected precisely via GPT GUIDs, impossible variants greyed out with reasons

Path 2: USB Installation Stick

Pre-configured FAT32/MBR stick installs Ubuntu on any UEFI PC – with safety prompt or fully automated

Tech Stack

.NET 10 / WPF

Ubuntu 26.04 LTS

Autoinstall (subiquity)

UEFI + GPT

shim + GRUB

Single-File SeleneOS.exe

Roadmap

Phase 1 – Selene OS Core

WPF wizard, system checks, partitioning, bootloader setup

Current

Phase 2 – Autoinstall & Desktop

Autoinstall configuration (subiquity/curtin), desktop meta packages, user & locale setup

Phase 3 – USB Stick & Management

USB installation stick, bootloader management, repair tools

Phase 4 – Release

Hardware testing, documentation, first release of Selene OS