Cosmic: System 76's New GNU/Linux Desktop Environment Written in Rust
Executive Summary
System76 is developing Cosmic, a new GNU/Linux desktop environment written from the ground up in Rust. This decision aligns with a major industry push towards memory safe languages to enhance software security and stability, a trend recently highlighted by the White House. By building Cosmic in Rust, System76 moves away from the extension-based customization of GNOME used in previous versions of Pop!_OS. This gives them full control over the development roadmap and allows them to create a more stable, secure, and performant desktop experience by design, free from the limitations of third party platforms.
The core innovation of Cosmic is its design philosophy, which synthesizes the user friendliness of traditional graphical desktops with the efficiency of keyboard driven tiling window managers. Its central feature is a hybrid window management system that integrates auto tiling as a first class, graphically configured citizen, providing the power of tiling without the steep learning curve of text file configuration. This principle of stable, integrated customization is applied to the entire shell. The desktop's cohesiveness is ensured by its technical foundation, where all native components and applications are built with a single, modern, GPU accelerated Rust toolkit called iced.
Cosmic's immediate future is to serve as the default desktop for Pop!_OS, which will be its primary showcase. Its long term success depends on the maturation of its iced toolkit and its adoption by the broader GNU/Linux community. The project faces significant challenges in competing with the feature completeness of established environments like GNOME and KDE Plasma. Consequently, Cosmic is positioned to succeed not by replacing these incumbents, but by effectively serving a specific user niche that desires a powerful, keyboard driven workflow without sacrificing the polish and graphical accessibility of a modern desktop.
Keywords: Cosmic, System76, Pop!_OS, Rust, GNU/Linux, Desktop Environment, Memory Safety, iced toolkit, Tiling Window Manager, Hybrid Window Management, Auto-tiling, User Experience, Customization, GNOME, KDE Plasma, i3, Keyboard-driven workflow, Software Security, GPU rendering, Free Software, Open Source
Glossary of Terms
├─ Core Concepts
│ ├─ Free Software: A philosophy focused on user freedom to run, copy, distribute, study, change and improve the software.
│ ├─ Open Source: A development model where source code is made publicly available for collaboration and transparency.
│ ├─ Software Security: The practice of protecting software from bugs and vulnerabilities that could be exploited.
│ └─ User Experience (UX): The overall feeling and ease-of-use a person has when interacting with a piece of software.
│
├─ Operating Systems (OS)
│ ├─ GNU/Linux: A family of operating systems combining the Linux kernel with tools from the GNU Project.
│ └─ Pop!_OS: The specific GNU/Linux distribution developed by System76.
│
├─ Desktop Interface & Windowing
│ ├─ Auto-tiling: The name for Cosmic's feature that automatically arranges windows into tiles.
│ ├─ Customization: The ability for users to alter the appearance and behavior of the desktop.
│ ├─ Desktop Environment (DE): The complete graphical user interface on top of an OS, including icons, windows, and toolbars.
│ │ ├─ GNOME: A popular DE known for its modern, simple design.
│ │ └─ KDE Plasma: A highly feature-rich and customizable DE.
│ ├─ Hybrid Window Management: A system that combines both traditional "floating" windows and an automatic tiling layout.
│ ├─ Keyboard-driven workflow: A method of using the computer that prioritizes keyboard shortcuts over using a mouse.
│ └─ Tiling Window Manager: A window manager that automatically arranges windows in a grid (tiles) without overlapping.
│ └─ i3: A popular, minimalist tiling window manager controlled primarily by the keyboard.
│
└─ Technical Details
├─ Cosmic: The new desktop environment developed by System76, which is the subject of the article.
├─ GPU Rendering: Using the computer's dedicated Graphics Processing Unit (GPU) to draw the desktop interface, which can improve performance and smoothness.
├─ iced toolkit: The specific software library (GUI toolkit) used to build Cosmic's graphical interface components.
├─ Memory Safety: A feature of a programming language that prevents entire classes of bugs that can lead to crashes or security holes.
├─ Rust: The programming language used to build Cosmic, known for its focus on performance and memory safety.
└─ System76: The US-based computer manufacturer that develops Pop!_OS and Cosmic.
Introduction
In February of 2024, the U.S. White House sent shockwaves through the global computer science community. It released a report titled "Back to the Building Blocks: A Path Toward Secure and Measurable Software," which recommended a fundamental shift: software developers should move to memory-safe programming languages like Rust.
So, what is memory safety? It's a property of a computer program that ensures memory pointers or references always point to valid locations. This prevents common but dangerous errors where memory is accessed in unintended ways. These bugs can lead to program crashes or, worse, critical security vulnerabilities. As the White House report emphasized, many of these safety issues can be eliminated by design when using a memory-safe language like Rust.
The report was well-received, galvanizing a movement already underway in the tech community. In its wake, many new initiatives were announced. For example, Canonical, the company behind the Ubuntu GNU/Linux distribution, is actively working to integrate Rust-based replacements for the GNU Coreutils, fundamental programs like `cp` and `ls` that are the bedrock of Linux systems.
At the forefront of this movement is System76, a Denver, Colorado-based company known for selling computers with GNU/Linux pre-installed. Capitalizing on the power and popularity of Rust, they are creating a brand-new GNU/Linux desktop environment from the ground up: Cosmic. While built for their own Pop!_OS, Cosmic is engineered with portability in mind; in theory, there's no reason it couldn't be adapted for other Unix-like operating systems like FreeBSD or even macOS.
My own journey to Pop!_OS is a personal one. From 2004 to 2021, Fedora was my GNU/Linux distribution of choice. However, in 2021, a simple game controller I bought on Amazon refused to work with it. I had heard good things about System76 and their Ubuntu-based distribution, Pop!_OS, so I decided to give it a try. Four years later, Pop!_OS is the operating system I run on all my desktop and laptop computers. Fedora remains a solid OS (I still run it on my file server), but Pop!_OS won me over on the desktop.
Given my reliance on Pop!_OS, I was extremely excited when Cosmic was announced and installed it as soon as it was available. I'm glad that I did, and I anticipate that Pop!_OS with the Cosmic desktop will be my GNU/Linux distro for the foreseeable future. In this article, I'll explore what Cosmic is, why System76 chose to write a new desktop environment in Rust, its standout features, and what the future likely holds. I hope you enjoy the tour. Let's dive in!
A. What Cosmic Is
Cosmic is a desktop environment developed by System76. It is built as a complete, integrated desktop experience that includes a compositor, panels, a dock, and applications, positioning it as an alternative to environments like GNOME, KDE Plasma, and XFCE. Its primary initial use is to serve as the default desktop for System76's Pop!_OS distribution, but it is also packaged for use on other GNU/Linux systems.
Cosmic is distinguished by its technical foundation. It is written primarily in the Rust programming language and utilizes `iced`, a Rust-native GUI toolkit. This choice of technology is intended to leverage Rust's language features related to memory safety and performance.
It is also a separate project from the previous "COSMIC" experience on Pop!_OS, which was a set of extensions for the GNOME desktop. The new Cosmic is a complete rewrite that does not share a codebase with GNOME. It is a distinct desktop environment with its own compositor, window manager, panels, applets, and system settings. The project aims to provide a cohesive user experience through its integrated components.
B. Why System 76 Chose to Write Cosmic in Rust
The decision by System76 to create a new desktop environment from scratch wasn't made lightly. For years, they successfully built their Pop!_OS user experience on top of GNOME, developing the original COSMIC extensions to tailor it to their vision. However, this approach had inherent limitations. Building on another platform meant they were always subject to upstream changes that could break their extensions, requiring constant maintenance. They wanted deeper control to innovate and deliver a truly polished and reliable experience without compromise.
This ambition required a modern technological foundation, and they chose Rust as the cornerstone for several critical reasons. The primary benefit is memory safety. Traditional desktop environments are written in languages like C++, which are powerful but prone to memory bugs that lead to crashes and major security vulnerabilities. Rust's unique ownership and borrowing model prevents these entire classes of errors during the compilation process, not after the software has been shipped. This allows System76 to build a more stable and secure desktop by design.
Beyond safety, performance was a key factor. Rust provides the low-level control needed for a fast and responsive system, achieving speeds comparable to C++ without the associated safety risks. This is essential for a desktop environment, where smooth animations, instant feedback, and efficient resource usage directly impact the user's experience. Furthermore, Rust has excellent support for concurrency, making it easier to write code that can handle many tasks at once without freezing or stuttering.
Ultimately, choosing Rust was a strategic bet on the future. By investing in a modern, safe, and performant language, System76 is building a foundation they can completely control for the next decade. This move frees them from the development cycle of other projects and empowers them to innovate faster, creating a cohesive and refined desktop environment that fully realizes their vision for the ideal GNU/Linux user experience.
C. The Features of Cosmic
Cosmic's design philosophy establishes a new category of desktop by synthesizing the graphical ease-of-use from traditional environments like GNOME with the keyboard-driven efficiency of tiling window managers like i3. The goal is a workflow-oriented system that combines the major benefits of both approaches while mitigating their respective compromises, offering power to experts without alienating newcomers.
The window management system is the centerpiece of this philosophy. It operates as a hybrid system where auto-tiling is a built-in, first-class feature, not a third-party extension. Users can toggle between traditional floating windows and an automatic tiling layout on a per-workspace or per-application basis. While tiled, windows are managed with keyboard shortcuts for navigation and resizing. This system's key differentiator is its graphical configuration; tiling behavior, window gaps, and floating exceptions are all controlled through the settings panel. This approach provides the structured workflow of a tiling manager while directly addressing the steep learning curve associated with the complex text-file configurations required by i3 or Sway.
This principle of stable, integrated customization defines the entire desktop shell. The Cosmic Panel and Dock are fully configurable through the native settings application, allowing users to adjust position, size, and contained applets. This design stands in direct contrast to environments like GNOME, where similar modifications rely on external extensions that are prone to breaking with system updates. The application launcher serves as a central command hub for this workflow, integrating application launching, file searching, and command execution into a single, keyboard-driven interface that consolidates the user's focus.
The desktop's cohesiveness is a direct result of its technical foundation. All native components are built with `iced`, a modern GUI toolkit written in Rust that leverages GPU rendering. This decision to build a new toolkit is a significant departure from the common practice of using the mature, C/C++-based GTK and Qt libraries, and represents a long-term investment in the performance and memory-safety features of Rust at the graphical layer. The core application suite demonstrates the potential of this foundation, including the GPU-accelerated Cosmic Terminal for low-latency text rendering, the Cosmic Edit text editor, the Cosmic Files file manager, and the Cosmic Settings panel that governs the entire environment.
D. The Likely Future of Cosmic
The future of the Cosmic desktop environment will likely be defined by a phased journey from a flagship product to a viable, community-supported alternative. Its most immediate future is tied to Pop!_OS, where it is set to become the default desktop environment. This initial release will serve as the primary showcase and litmus test for its performance, stability, and the successful realization of its hybrid workflow philosophy. Beyond this first step, Cosmic's long-term viability will depend on its adoption by the wider GNU/Linux community. Its success will be measured by its availability and maintenance in the repositories of major distributions like Fedora and Arch Linux, a process that relies on volunteer effort and a compelling reason to choose Cosmic over its deeply entrenched competitors.
Technically, Cosmic's future is in a symbiotic relationship with its underlying GUI toolkit, `iced`. The maturation of the desktop environment is intrinsically linked to the maturation of the toolkit. For Cosmic to achieve feature parity with established desktops, `iced` must evolve to support a comprehensive set of widgets, robust accessibility features, and the performance optimizations required for a diverse range of hardware. This represents a significant long-term development challenge. The growth of a native application ecosystem also hinges on `iced`'s success; the toolkit must become stable and well-documented enough to attract third-party developers who are willing to invest in a platform outside of the dominant GTK and Qt ecosystems.
The greatest challenge for Cosmic will be competing for mindshare and feature completeness against the incumbent desktop environments, GNOME and KDE Plasma. These projects have over two decades of development behind them, resulting in an immense feature set, broad internationalization, and extensive hardware compatibility. Cosmic will not be able to compete on a feature-for-feature basis for many years. Instead, its success will depend on how well it serves its target niche: users who desire the efficiency of a tiling workflow without sacrificing the convenience and polish of a modern, graphically-configured desktop. If it can prove that its core design philosophy solves real-world usability problems for this demographic, it can carve out a sustainable position in the Linux ecosystem. Its ultimate legacy may not be to replace the incumbents, but to validate Rust as a viable language for large-scale GUI development and to popularize a new, hybrid approach to desktop.
Conclusions
System76's Cosmic desktop environment represents a significant and ambitious undertaking, born from both a pragmatic need for platform independence and a wider industry shift towards memory-safe programming. It is more than a new interface; it is a ground-up effort to build a more secure, stable, and cohesive desktop by leveraging the modern capabilities of the Rust programming language. By taking on the immense challenge of developing not only a new desktop shell but also its own GUI toolkit, System76 is making a long-term investment in controlling the future of its software ecosystem.
As this article has detailed, Cosmic's core value proposition is its attempt to unify two disparate desktop paradigms: the accessibility of traditional graphical interfaces and the efficiency of keyboard-driven tiling. The resulting hybrid system, with its graphically configured tiling and emphasis on stable, integrated customization, is designed to serve a growing niche of power users who find traditional desktops too rigid and dedicated tiling managers too esoteric. This specific focus is both its greatest strength and the key to its potential success in a market dominated by mature incumbents.
Ultimately, Cosmic is a high-stakes wager on a specific vision for the future of the GNU/Linux desktop. Its success is not guaranteed and hinges on the continued maturation of its iced toolkit and its ability to attract a dedicated community. However, whether it becomes a major player or remains a niche project, its development will provide invaluable data on the viability of Rust for large-scale GUI applications and on the demand for a desktop that truly bridges the gap between power and accessibility.
```
Cosmic: System 76's New GNU/Linux Desktop Environment Written in Rust
├─ Executive Summary
│ ├─ Core Thesis: System76 is developing Cosmic in Rust, aligning with the industry's push for memory-safe languages.
│ ├─ Key Innovation: A hybrid design synthesizing user-friendly graphical desktops with efficient tiling window managers.
│ └─ Outlook: Success depends on maturing the 'iced' toolkit and capturing a niche user base.
│
├─ Introduction
│ ├─ Industry Context: Cites the 2024 White House report recommending memory-safe languages like Rust.
│ ├─ Definition: Explains what memory safety is and its importance for preventing software vulnerabilities.
│ ├─ The Subject: Introduces System76 and their project, the Cosmic desktop, built for Pop!_OS.
│ └─ Author's Anecdote: Details the personal journey from using Fedora to adopting Pop!_OS.
│
├─ A. What Cosmic Is
│ ├─ Definition: A complete, integrated desktop environment positioned as an alternative to GNOME, KDE Plasma, etc.
│ ├─ Technical Foundation: Built primarily in the Rust programming language using the 'iced' GUI toolkit.
│ └─ Key Distinction: It is a complete rewrite and not a continuation of the previous COSMIC extensions for GNOME.
│
├─ B. Why System 76 Chose to Write Cosmic in Rust
│ ├─ Primary Motivation: To move beyond the limitations of GNOME extensions and gain full control over the platform.
│ ├─ Technical Advantage 1 (Memory Safety): To build a more stable and secure desktop by preventing memory-related bugs.
│ ├─ Technical Advantage 2 (Performance): To achieve C++ level speeds and responsiveness without sacrificing safety.
│ └─ Strategic Vision: A long-term investment to control their own development cycle and innovate faster.
│
├─ C. The Features of Cosmic
│ ├─ Design Philosophy: To create a new category of desktop that is both powerful for experts and approachable for newcomers.
│ ├─ Window Management: Features a built-in, graphically configured, hybrid auto-tiling system.
│ ├─ Desktop Shell: Offers stable, integrated customization for the Panel, Dock, and a unified App Launcher.
│ └─ Native Applications: A cohesive suite (Terminal, Edit, Files) built on the Rust-native 'iced' toolkit.
│
├─ D. The Likely Future of Cosmic
│ ├─ Rollout & Adoption: Will debut as the default on Pop!_OS, with wider community adoption as a long-term goal.
│ ├─ Technical Dependency: Its future is intrinsically linked to the maturation of its underlying 'iced' toolkit.
│ └─ Market Position: Aims to succeed by serving a niche that wants a hybrid tiling/graphical workflow, rather than directly competing with GNOME/KDE on feature count.
│
├─ Conclusions
│ ├─ Summary: Cosmic is an ambitious project driven by platform independence and the push for memory safety.
│ ├─ Value Proposition: Its core value is the unification of accessible graphical interfaces with efficient tiling workflows.
│ └─ Final Outlook: A high-stakes project whose success will validate Rust for GUI development and the hybrid desktop model.
│
└─ Appendices
├─ Keywords: A comma-separated list of the article's most important terms.
├─ Glossary of Terms: An ASCII tree providing definitions for technical terms.
└─ References: A list of cited sources, including the White House report and System76's website.
```
References:
- The White House. "Back to the Building Blocks: A Path Toward Secure and Measurable Software". February 2024. Retrieved 20250926 from https://bidenwhitehouse.archives.gov/wp-content/uploads/2024/02/Final-ONCD-Technical-Report.pdf
- Redox OS. Redox OS Homepage. Retrieved 20250926 from https://www.redox-os.org/
- System 76. Cosmic desktop. Retrieved 20250926 from https://system76.com/cosmic