Introduction to PureOS

PureOS is a free and open-source operating system designed with privacy, security, and freedom at its core. Developed by Purism, it is based on Debian and endorsed by the Free Software Foundation. PureOS aims to provide users with a fully libre computing experience—one that avoids proprietary code and proprietary firmware whenever possible. It is ideal for users who value digital privacy and control over their devices, offering a seamless desktop experience as well as a mobile interface in the form of the Librem 5 smartphone.

History and Origins

PureOS traces its roots back to 2014, when Purism was founded with a mission to create hardware and software respecting user rights. The team recognized a gap in the market for a desktop operating system free from proprietary components. By forking Debian Stable and rigorously removing non-free packages, they created PureOS. In 2017, the Free Software Foundation gave official endorsement, citing PureOS as compliant with its stringent criteria for complete free software distributions.

What Is PureOS?

PureOS stands for an operating system that embraces four core pillars:

• Privacy: Collection of no telemetry by default.
• Security: Hardened configurations and sandboxing mechanisms.
• Freedom: Uses only free software as defined by the Free Software Foundation.
• Transparency: All code is open and auditable, with public repositories.

It is officially recognized by the Free Software Foundation, making it one of the few distributions that can claim a 100% free software stack.

Core Principles

• Software Freedom: Every package in the main repository meets the FSF’s standards.
• User Privacy: No background data collection, default use of privacy-respecting search engines and browsers.
• System Security: Incorporates AppArmor profiles, builds with stack protections, and encourages encrypted storage.
• Community Collaboration: Development is open, with contributions from volunteers and Purism engineers alike.

Technical Basis

PureOS is derived from Debian Stable. It uses the APT packaging system and .deb packages, ensuring compatibility with a large ecosystem of Debian software. The default desktop environment on laptops is GNOME, while the mobile version—Phosh—is tailored for touchscreen interfaces. The kernel is the latest long-term support (LTS) Linux kernel, compiled with options favoring security and performance.

How PureOS Works

Understanding how PureOS functions involves examining its architecture, default applications, security mechanisms, and package management.

System Architecture

The foundation of PureOS is the Linux kernel. It loads free firmware and drivers, avoiding proprietary blobs. On top of the kernel sits systemd as the init system, managing services and boot processes. Core libraries (glibc, libstdc ) provide the standard interfaces for applications, while Mesa delivers open-source graphics drivers.

Desktop Environment

On laptops and desktops, PureOS ships with GNOME:

• GNOME Shell for window management.
• GNOME Applications such as Files (Nautilus), Terminal, and Software Center.
• Wayland as the default display server for improved security and smoother rendering.

For the Librem 5 smartphone, Phosh (a mobile shell based on GNOME technologies) provides:

• Adaptive UI that scales between phone and desktop layouts.
• Libhandy for responsive design in applications.
• Calls and Messaging integrated through Calls and Messages apps built on Freedreno telephony stacks.

Package Management

PureOS uses APT with repositories categorized as:

• main: Fully free software, FSF-endorsed.
• security: Patches and updates tracked from Debian Security.
• pureos: Purism’s own repository for specialized packages like Librem hardware drivers.

The Software Center (GNOME Software) provides a graphical interface, while the command line offers power users full control. Advanced features include:

• Pinning to prefer PureOS packages over Debian ones.
• Snapshots with Timeshift integration for system rollbacks.

Security and Privacy Features

PureOS integrates multiple layers of security:

• AppArmor profiles on critical services to contain potential breaches.
• Encrypted Installation wizard offering full-disk encryption (LUKS) by default.
• Firewall preconfigured with ufw (Uncomplicated Firewall) to block unwanted inbound connections.
• Secure Boot support on Librem hardware, ensuring only trusted kernels and bootloaders run.

Privacy enhancements include:

• PureBrowser (a hardened version of Firefox using DuckDuckGo and HTTPS-Everywhere).
• Tracker Blocking and ad-blocking integrated.
• Metadata Scrubbing tools for documents and images.
• Onion Services support via Tor Browser launcher.

PureOS Editions and Devices

PureOS is tailored to multiple platforms, ensuring a unified experience across desktop and mobile.

Librem Laptops

Librem 13, Librem 14:

• Hardware Kill Switches for camera, microphone, and wireless.
• PureBoot chain of trust with coreboot firmware.
• Custom Drivers in the pureos repository.

Librem 5 Phone

The world’s first privacy-focused smartphone running a fully free software stack:

• Phosh shell for adaptive touchscreen interface.
• Librem 5 USA edition with domestically sourced components.
• Modular Hardware Design allowing battery, modem and camera replacements.

Virtual Machine and Installer Edition

PureOS provides live ISOs for easy testing in virtual machines or on USB drives. The installer edition offers:

• Graphical, user-friendly installation wizard.
• Manual partitioning options.
• Pre-configuration for encrypted root filesystems.

Orientation and Use Cases

PureOS caters to several user profiles, each benefiting from its privacy- and freedom-centric design.

Everyday Desktop User

People who browse the web, stream media, and use office suites:

• LibreOffice for document editing.
• Thunderbird for email with OpenPGP support.
• PureBrowser for secure web browsing.

Developers and Power Users

Software engineers and sysadmins:

• Build-essential packages for compiling C/C .
• Python, Node.js, Rust toolchains available in main repositories.
• Docker and Podman for containerization.
• Timeshift for snapshot management and safe rollbacks.

Educational and Research Environments

Schools and labs valuing open standards:

• Mathematical software like Octave and Gnuplot.
• Scientific libraries via apt (SciPy, NumPy, R).
• Privacy-focused tools for digital forensics and secure communication.

Installation and First Steps

System Requirements

Hardware Minimum

• 64-bit processor (x86_64 or ARMv8).
• 2 GB RAM (4 GB recommended).
• 10 GB free disk space (20 GB recommended for comfortable usage).
• USB port or SD card slot for live media.

Recommended Specifications

• 4-core processor (i5/Ryzen 5 or better).
• 8 GB RAM or more.
• Solid-state drive (SSD) for faster performance.
• Graphics hardware supported by Mesa drivers.

Installation Steps

• Download the latest ISO from https://pureos.net/download.
• Verify the image signature with GPG: gpg –verify.
• Create a bootable USB using Etcher or dd.
• Boot the live media and select “Try PureOS” or “Install PureOS.”
• Follow the graphical installer: choose language, keyboard layout, and disk setup.
• Enable full-disk encryption with LUKS passphrase for enhanced security.
• Create user account and password, then reboot into your new system.

Curiosities and Unique Features

• FSF Endorsement: PureOS is among the few distros officially endorsed for using only free software.
• Hardware Kill Switches: Physical toggles to disable camera, mic, Wi-Fi, and Bluetooth on Librem laptops.
• PureBoot: A secure boot firmware stack replacing proprietary BIOS with coreboot and Heads.
• Debian Frozen Base: While based on Debian Stable, the core packages are occasionally re-synced for security patches.
• Dual-Use UI: Phosh on Librem 5 transforms seamlessly between mobile and desktop modes when connected to external displays.
• Community-Driven: Besides Purism engineers, volunteers worldwide contribute patches, translations, and documentation.
• OpenPGP Hotkey: Librem laptops feature a Built-in OpenPGP security token under the keyboard for password-less authentication.

Comparison with Other Distributions

Community and Development

PureOS maintains public repositories on GitLab. The community participates through issue reporting, merge requests, translations, and forum discussions.

Contribution

• Submit bug reports at https://source.puri.sm/Librem5/pureos-iso/-/issues.
• Propose patches via merge requests on the PureOS GitLab.
• Translate strings for GNOME and PureOS utilities.

Support

• Forums: User-to-user help at https://forums.puri.sm.
• IRC: Real-time chat on Libera.Chat #pureos channel.
• Documentation: Official guides and FAQs at https://docs.puri.sm/.

Conclusion

PureOS represents a dedicated effort to provide a fully free software operating system without sacrificing usability, performance, or design. By combining a Debian foundation with Purism’s hardware innovations, it offers seamless integration across laptops and mobile devices. Whether you are a privacy advocate, developer, or everyday user seeking a trustworthy computing environment, PureOS delivers a comprehensive solution rooted in digital freedom and transparency.