Krubuntu 26.04.1 LTS (KDE Plasma Edition)

A Pure, Bloat-Free, Open-Source Linux Distribution Built on Ubuntu 26.04 LTS & KDE Plasma.
Engineered using professional Infrastructure-as-Code (IaC) standards — No Cubic, No Bloat, No Compromises.

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📖 Table of Contents

• Overview
• Key Features
• System Architecture
• Hardware Enablement
• Software & Packaging Policy
• Quick Start: Build & Test
• Documentation Guides
• Contributing
• License

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🌟 Overview

Krubuntu is an open-source Linux operating system designed for users who want the rock-solid hardware support and extensive software ecosystem of Ubuntu LTS, paired with the speed, beauty, and modern Wayland architecture of KDE Plasma — completely free of bloatware, telemetry, and background overhead.

Unlike ordinary remaster projects that rely on manual snapshot tools like Cubic, Krubuntu is built strictly from cryptographic root sources using clean, reproducible shell automation scripts on an ephemeral chroot pipeline.

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🚀 Key Features

• Ubuntu 26.04.1 LTS Minimal Core: Pure Resolute Raccoon upstream base without unnecessary legacy daemons.
• KDE Plasma 6 (Wayland-First): Sleek, lightweight Breeze interface with 100% Wayland compositing, fractional display scaling, and fluid animations.
• Modern Sound Architecture: PipeWire 1.6 + WirePlumber out of the box with Intel Sound Open Firmware (SOF), ALSA UCM profiles, and Bluetooth LDAC/AptX/AAC codecs.
• High-Throughput Network Engine: Google BBR TCP congestion control pre-activated for ultra-low latency web browsing and maximum bandwidth saturation.
• Adaptive Memory Management:
  • systemd-zram-generator: In-RAM zstd swap engine providing 100% RAM expansion without physical disk thrashing.
  • earlyoom: Pop!_OS style freeze guard that terminates runaway memory leaks before the desktop locks up.
• Day-to-Day Productivity Apps:
  • Browser: Native Mozilla Firefox (.deb) directly from Mozilla's official signed APT repository (Zero Snap daemon overhead).
  • PDF & Documents: Okular universal document viewer.
  • Media Playback: VLC and FFmpeg with hardware VA-API video decode acceleration.
  • Utilities: Dolphin, Konsole, KWrite, Ark, Gwenview, Spectacle, and KDE Partition Manager.
• Zero Bloatware: No pre-installed games, no telemetry, no third-party trial software, no duplicate utilities.
• User-Empowered Packaging:
  • Snap: snapd is installed with Discover integration, but disabled at boot by default to preserve RAM and CPU cycles.
  • Flatpak: Flathub remote is pre-configured in a disabled state, allowing instant 1-click activation from KDE Discover Settings without terminal commands.
• Modern Installer: Calamares 3.3+ with Krubuntu branding, automated partition erase option, and target rootfs cleanup.
• Hybrid Bootloader: UEFI (x86_64) and Legacy BIOS hybrid ISO compatible with NVMe, SATA SSD, and USB flash media.

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🏗️ System Architecture

Krubuntu is built as Infrastructure-as-Code:

flowchart LR
    A["Ubuntu Base Tarball"] --> B["Clean Chroot Environment"]
    B --> C["Curated Package Manifest"]
    B --> D["RootFS System Overlay"]
    B --> E["Mozilla Official APT"]
    C --> F["Sanitization & Cleanup"]
    D --> F
    E --> F
    F --> G["zstd Multi-Threaded SquashFS"]
    G --> H["Hybrid UEFI/BIOS ISO Image"]

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For the complete technical breakdown of the chroot lifecycle, memory subsystems, and kernel tuning, see Architecture Documentation.

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⚡ Hardware Enablement

Krubuntu provides out-of-the-box support for modern and legacy PC hardware:

Hardware	Support Level	Implementation
Intel / AMD Laptops	Full Native	PipeWire + firmware-sof-signed + ALSA UCM (alsa-ucm-conf)
Display & GPU	Vulkan 1.3 & VA-API	Mesa 24.x (mesa-vulkan-drivers), Intel VA-API (intel-media-va-driver)
Wi-Fi 6 / 6E / 7	Out of the Box	NetworkManager + Netplan delegation + wpasupplicant
External USB / Disks	Plug & Play	NTFS-3G (ntfs-3g), exFAT (exfatprogs), FAT32 (dosfstools)
Power & Battery	Dynamic Profiles	power-profiles-daemon with KDE battery applet integration

For detailed hardware specifications, see Hardware Enablement Guide.

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📦 Software & Packaging Policy

Packaging Backend	Default State	How to Use / Toggle
Native APT (.deb)	Enabled (Primary)	sudo apt install <package> or Discover
Mozilla Firefox (.deb)	Enabled (Official Key)	Directly from Mozilla signing server
Flatpak (Flathub)	Pre-configured (Disabled)	1-Click checkbox in Discover Settings
Snap (Canonical)	Pre-installed (Disabled at boot)	Discover Settings or krubuntu-backend-manager

For complete rationale, pinning rules, and offline catalog details, read the Package Policy Guide.

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🛠️ Quick Start: Build & Test

1. Build the ISO with Docker (Recommended)

You can build the ISO on any Linux distribution (Fedora, Arch, Debian, Ubuntu):

# Clone the repository
git clone https://github.com/krinry/krubuntu.git
cd krubuntu

# Build inside isolated Ubuntu 26.04 builder container
./build.sh --docker

2. Test in QEMU

Immediately verify the generated ISO with hardware-accelerated KVM virtualization, duplex audio, and virtual disk:

./build.sh --test

3. Verify Checksum

cd output
sha256sum -c Krubuntu-26.04.1-amd64.iso.sha256

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📚 Documentation Guides

• Architecture & Engineering - Deep dive into build pipeline, zRAM, BBR sysctl, and Calamares.
• Hardware Enablement - Audio DSP, Vulkan, Wi-Fi 6/7, and power profiles.
• Package Management Policy - Snap/Flatpak philosophy, Mozilla deb integration, and Discover.
• Installation & Setup Guide - Flashing with Rufus/Etcher/Ventoy, BIOS settings, and dual-booting.
• Contributing Guide - Code standards, testing workflow, and pull request guidelines.

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🤝 Contributing

Contributions are warmly welcomed! Please see CONTRIBUTING.md for full instructions on setting up your environment, running tests, and submitting pull requests.

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📄 License

Krubuntu is open-source software licensed under the GNU General Public License v3.0 (GPL-3.0). Upstream components remain under their respective open-source licenses (Ubuntu, KDE, Linux Kernel, Mozilla).