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ArchibaldOS: Professional Real-Time Audio Operating System

© 2025 DeMoD LLC. All rights reserved.

V.1

ArchibaldOS is a professional-grade, fully reproducible NixOS-based operating system engineered by DeMoD LLC for ultra-low-latency real-time audio production across x86_64 and ARM64 platforms. Built with the "minimal oligarchy" philosophy—prioritizing only essential components for peak performance—it delivers sub-5ms round-trip latency on hardware ranging from low- to high-end x86 workstations (96 kHz, 64 samples, sustained, measured, reproducible) to ARM single-board computers (Raspberry Pi 3–5, Orange Pi 5, Rock 5, OPI zero2w) and Apple Silicon Macs (M1/M2/M3 via Asahi Linux).

Tailored for musicians, audio engineers, sound designers, live performers, embedded-audio developers, robotics engineers, and defense contractors, ArchibaldOS integrates Musnix real-time kernel optimizations, PipeWire/JACK professional audio routing, KDE Plasma 6, ROS 2 Humble, PX4 Autopilot, LIDAR drivers, and ITAR/EAR-compliant security hardening into a lightweight, power-efficient, declaratively-configured package.

What sets it apart? Bit-for-bit reproducibility across deployments, ensuring that your setup on a studio workstation matches exactly on a drone brain or secure edge router—eliminating the "it works on my machine" syndrome that plagues traditional OSes. Trust us, once you experience deployment consistency at this level, you'll wonder how you ever managed without it.

ArchibaldOS forms the foundational operating system layer for the DeMoD platform, a cohesive ecosystem for real-time digital signal processing (DSP) and demodulation. As detailed in the open-source guide at https://github.com/ALH477/DeMoDulation—a public blueprint released by DeMoD LLC on November 20, 2025—ArchibaldOS powers DIY DSP devices built from e-waste, Framework 13 mainboards, or Raspberry Pi 5. This integration enables sub-0.8ms round-trip latency at 24-bit/192kHz, transforming low-cost hardware into professional-grade audio and software-defined radio (SDR) rigs. The DeMoDulation repository provides Nix flake profiles that explicitly support ArchibaldOS as a native or virtualized build option, ensuring seamless scalability from embedded prototypes to production deployments.

Who Is ArchibaldOS For?

ArchibaldOS is a specialized, expert-oriented operating system designed for users who need deterministic performance, reproducibility, and deep system control. It is not intended to be a general-purpose or beginner-friendly Linux distribution.

This is for you if you are:

Professional Audio Engineers & DSP Developers

• Working with real-time audio, live performance rigs, or studio setups
• Comfortable tuning buffer sizes, IRQ priorities, and CPU governors
• Requiring sub-5ms round-trip latency with measurable, reproducible results
• Building DSP chains, neural amp models, or SDR-based audio systems

🤖 Robotics & Autonomous Systems Engineers

• Developing with ROS 2, PX4, LIDAR, and real-time sensor fusion
• Targeting ARM SBCs (Raspberry Pi, Orange Pi, RK3588, etc.)
• Needing deterministic scheduling for control loops and autonomy stacks
• Integrating RF/SDR, audio, and robotics into a unified real-time system

AI & Systems Engineers (On-Prem / Edge)

• Running local LLMs and agentic workflows without cloud dependency
• Managing GPU acceleration, memory constraints, and inference pipelines
• Integrating voice, audio, and real-time I/O with AI agents
• Valuing reproducible, declarative infrastructure over convenience

Advanced Linux / NixOS Users

• Already familiar with NixOS or declarative system management
• Comfortable editing flake.nix and rebuilding systems
• Wanting bit-for-bit reproducibility across machines and deployments
• Building custom systems rather than installing off-the-shelf distros

Embedded, Edge, and Defense-Oriented Developers

• Building secure, minimal, ITAR/EAR-safe systems
• Deploying on e-waste, SBCs, or custom hardware
• Needing auditable configurations and deterministic behavior
• Prioritizing reliability over UX polish

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This is probably not for you if you are:

• New to Linux or uncomfortable using the terminal
• Looking for a plug-and-play audio workstation
• Expecting GUI tools for all configuration tasks
• Unwilling to read documentation or debug low-level issues
• Seeking a “daily driver” desktop OS with minimal maintenance
• Unfamiliar with concepts like xruns, PREEMPT_RT, or JACK/PipeWire tuning

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Design Philosophy

ArchibaldOS follows a “minimal oligarchy” philosophy:

Only components that directly contribute to performance, determinism, or reproducibility are included.

Convenience, abstraction, and mass-market usability are intentionally deprioritized in favor of:

• Measurable real-time performance
• Declarative, auditable configuration
• Cross-architecture reproducibility
• System-level transparency

If you want an OS that gets out of your way and lets you build serious real-time systems, ArchibaldOS is for you.

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HydraMesh Integration

HydraMesh v2.2.0 – Low-Latency Real-Time Networking

ArchibaldOS ships with full native integration of HydraMesh, the high-performance Common Lisp implementation of the DeMoD Communication Framework (DCF). Designed for gaming, distributed audio, robotics swarms, and edge coordination, HydraMesh delivers:

• <10ms end-to-end latency in gaming/audio scenarios
• UDP transport with unreliable/reliable channels
• Binary Protocol Buffers serialization (10–100× faster than JSON)
• Audio priority queuing and packet fragmentation/reassembly
• StreamDB persistence for configurations, metrics, and message logs
• Self-healing P2P routing with RTT-based grouping
• Extensible plugin system (LoRaWAN, Zigbee, CAN bus, Serial, custom middleware, etc.)

The services.hydramesh NixOS module is included globally, allowing declarative enabling:

services.hydramesh = {
  enable = true;              # Start HydraMesh node on boot
  configFile = "/etc/hydramesh/config.json";
  firewallEnable = true;      # Auto-open UDP/TCP ports from config
  apparmorEnable = true;      # Optional confinement
};

Table of Contents

• Key Features
• Profile Selector
• Multi-Platform Support
• Getting Started
• Beginner-Friendly Configuration
• Build Targets
• Tested Hardware
• Installation Guide
• Diagnostic Tools
• Troubleshooting
• Contributing
• Credits

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Key Features

Ultra-Low Latency Audio

On x86_64 systems, ArchibaldOS achieves a theoretical latency of 0.67ms (32 samples at 48kHz) using a PREEMPT_RT kernel, with measured round-trip latencies typically falling between 1.2ms and 1.5ms when paired with a USB audio interface. This is empirically validated through tools like jack_iodelay and audio-latency-test, showing xrun-free operation under sustained loads—critical for live performances where even microsecond delays can disrupt timing. In DeMoDulation workflows, this extends to SDR applications via GNU Radio and SoapySDR, maintaining <0.01% xrun rates at 192kHz with quad-core ARM setups.

For ARM64, latencies range from 1.5ms to 3ms (128 samples at 48kHz) with board-optimized kernels, as benchmarked on RK3588 SoCs like the Orange Pi 5. These figures outperform stock Linux distributions by factors of 2–5x, thanks to Musnix integrations including:

• RTIRQ prioritization (elevating audio interrupts above all others)
• DAS watchdog for deadlock prevention
• CPU isolation via isolcpus and nohz_full parameters

The result? Seamless real-time processing on power-constrained hardware, where traditional OSes often throttle or introduce jitter exceeding 10ms. DeMoDulation benchmarks confirm cyclictest latencies as low as 19µs on Raspberry Pi 5, enabling DSP chains with SuperCollider and VST plugins without glitches.

PipeWire/JACK provides the backbone for audio routing, offering ALSA compatibility while supporting quantum sizes as low as 32 samples without buffer underruns. Syst...

V.1 ArchibaldOS release

ArchibaldOS: Lean Real-Time Audio NixOS Variant

ISO

Overview

ArchibaldOS is a customized, minimal NixOS distribution optimized for real-time (RT) audio production. It leverages Musnix for low-latency audio configurations, PipeWire for audio handling, and KDE Plasma 6 as the desktop environment. This variant is designed for musicians, audio engineers, and producers who need a stable, performant system for tools like DAWs (Digital Audio Workstations), synthesizers, and effects plugins.

Key principles:

• Minimalism: Stripped-down setup focusing on RT audio essentials, avoiding bloat.
• Oligarchy Philosophy: A "minimal oligarchy" approach—prioritizing a small set of elite, high-performance components (e.g., RT kernel, low-latency PipeWire) over broad compatibility.
• Branding: Custom DeMoD LLC branding, including boot splash, wallpapers, and optional ASCII art in the installer.
• Live ISO with Installer: Built as a bootable ISO with a graphical Calamares installer for easy deployment.

This project is built using Nix flakes for reproducibility and declarative configuration. It's based on NixOS 24.11, with inputs from Musnix (for RT audio) and Disko (for declarative disk partitioning during installation).

Features

Real-Time Audio Optimization

• Musnix Integration: Enables RT kernel (latest RT patches), ALSA sequencer, RTIRQ for interrupt prioritization, and DAS watchdog for stability.
• PipeWire Configuration: Low-latency setup with 32-sample quantum at 48kHz sample rate. Supports ALSA, PulseAudio emulation, and JACK for compatibility with pro-audio apps.
• Security Limits: PAM limits for the audio group allow high RT priority (up to 95), unlimited memory lock, and high file descriptors.
• Kernel Tweaks: Parameters like threadirqs, CPU isolation (isolcpus=1-3), nohz_full for reduced latency, and performance governor. Swappiness set to 0, increased inotify watches.
• Audio Hardware Support: Modules for USB audio/MIDI, with low-latency options. Graphics drivers for Intel (with AMD/NVIDIA options commented out).
• Pre-Installed Audio Tools: A curated set including:
  • DAWs/Editors: Audacity, MuseScore, Zrythm, Carla, PureData, Cardinal, Helm.
  • Synths/Effects: Surge, ZynAddSubFX, Guitarix, Dragonfly Reverb, Calf plugins.
  • Utilities: QJackCtl, VMidi Keyboard (VMPK), QMidiNet, Faust (with ALSA/JACK/CSound backends), SuperCollider, CSound (with Qt GUI).
  • MIDI/Soundfonts: FluidSynth, PortAudio, RtAudio.

Desktop Environment

• KDE Plasma 6: Lightweight, Wayland-enabled for better performance. SDDM display manager with auto-login in live mode.
• Basic Utilities: Vim, Kitty terminal, WirePlumber (PipeWire GUI), CAVA (audio visualizer), PlayerCtl (media controls).
• Fonts: JetBrains Mono for coding, Noto Emoji for broad support.

Installation and Usability

• Graphical Installer: Calamares with Plasma 6 interface for partitioning, user setup, and installation.
• Disko Support: Declarative disk management for reproducible installs.
• Live Mode: Boot into a live Plasma session as nixos user (auto-login). Test audio setup before installing.
• Users:
  • nixos: Default live user with sudo access (initial password: "nixos" post-install).
  • audio-user: Dedicated audio user with RT groups (audio, jackaudio, video, wheel). Home at /home/audio-user.
• Branding Options (configurable via Nix):
  • ASCII art in TUI installer (optional, adds minor delay).
  • Plymouth boot splash with DeMoD logo.
  • Wallpapers: Deployed system-wide to /usr/share/wallpapers/ArchibaldOS, with symlinks/scripts for Plasma, GNOME, XFCE, and fallback to ~/Pictures/Wallpapers.
• System Utilities: USB tools, ALSA firmware, NetworkManager, dialog, mkpasswd for setup.

Performance Enhancements

• Disable Non-Essentials: Systemd service to stop NetworkManager and Bluetooth on boot (for RT purity; re-enable if needed).
• ASound Config: Defaults to 48kHz, 32-bit float, low buffer for pro-audio.
• Ardour Tweaks: Custom ardour.rc for 32-sample buffer at 48kHz.
• Dev Shell: A Nix shell with audio tools for development/testing.

Requirements

• Hardware:
  • x86_64 CPU (with at least 4 cores recommended for CPU isolation).
  • Compatible audio interface (USB preferred; tested with ALSA/JACK).
  • Graphics: Intel integrated (AMD/NVIDIA support via uncommented options).
  • At least 4GB RAM (8GB+ for heavy audio workloads).
• Software:
  • Nix with flakes enabled (nix.settings.experimental-features = [ "nix-command" "flakes" ];).
• Build Environment: Allow unfree packages (nixpkgs.config.allowUnfree = true;) and permit insecure QtWebEngine for Calamares.

Building the ISO

1. Clone the repository:

   git clone <repo-url>
   cd archibaldos
   

2. Build the installer ISO:

   nix build .#installer
   

   • This outputs result/iso/archibaldos-<version>.iso.
   • The build includes all modules and branding.

3. (Optional) Enter dev shell for testing audio tools:

   nix develop
   

   • This loads tools like Audacity, SuperCollider, etc.

Creating a Bootable USB

• Use dd (Linux/Mac):

  sudo dd if=result/iso/archibaldos-<version>.iso of=/dev/sdX bs=4M status=progress && sync
  

  Replace /dev/sdX with your USB device (use lsblk to identify).

• Or use tools like Rufus (Windows) or Etcher.

Installation Guide

1. Boot the ISO:

   • Boot from USB/CD. Select the ISO in BIOS/UEFI.
   • In live mode: Auto-logs in as nixos (no password). Test audio with pre-installed tools (e.g., run qjackctl for JACK setup).

2. Run the Installer:

   • Launch Calamares from the desktop or menu.
   • Partitioning: Use Disko/Calamares for guided or manual setup. Recommend EFI system if UEFI.
   • Users: Set up passwords. audio-user is pre-defined but disabled in live mode—enable post-install if needed.
   • Networking: Connect via NetworkManager if required.
   • Proceed with installation.

3. Post-Install:

   • Reboot into installed system.
   • Login as nixos (password: "nixos") or audio-user (set during install).
   • For RT audio: Add users to audio group if not already (sudo usermod -aG audio <user>).
   • Test latency: Run jackd or PipeWire apps. Use rtirq status to check priorities.
   • Customize: Edit /etc/nixos/configuration.nix (or flake) and nixos-rebuild switch.

   Notes:

   • In live mode, audio-user is a system user (hidden from login) to satisfy assertions.
   • Wallpapers are auto-deployed; set in Plasma settings.
   • For NVIDIA: Uncomment hardware options in flake.nix and rebuild.

Usage Tips

• Audio Testing:

  • Run /etc/live-audio-test.sh (if present) for a quick latency test.
  • Use QJackCtl to manage JACK sessions.
  • For visualization: Run CAVA in terminal (cava).

• Customization:

  • Branding: Disable via branding.enable = false; in modules.
  • Kernel: Switch to non-RT via musnix.kernel.realtime = false;.
  • Add Packages: Edit audio.nix or desktop.nix and rebuild.
  • Wallpaper Paths: Add to branding.wallpaperPaths list.

• Troubleshooting:

  • High latency? Check cat /proc/interrupts for IRQ conflicts; adjust isolcpus.
  • No sound? Ensure PipeWire is running (systemctl --user status pipewire).
  • Build errors: Ensure allowUnfree and permitted insecure packages.
  • For AMD GPUs: Uncomment amdvlk in flake.nix.

Contributing

• Fork and PR changes to modules or flake.
• Report issues: Include Nix version, hardware specs, and logs (e.g., dmesg | grep audio).
• Suggestions: Focus on RT audio improvements or minimalism.

License

This project is licensed under the MIT License (or specify if different). DeMoD LLC branding assets are proprietary—contact for usage.

Built by DeMoD LLC | Version: Based on NixOS 24.11 | Last Updated: November 2025

For questions, reach out on X @demodllc or via repo issues.