Discord rewritten in Rust: new client is faster and uses 70% less RAM

Discord is currently testing a brand-new desktop client rewritten entirely in Rust to replace its aging Electron-based application. According to a video shared by Discord co-founder and CTO Stanislav Vishnevskiy, the new Rust client loads its friends list before the traditional Electron app can even get past its initial loading screen.

• The new Discord client boots up instantly from a cold start without any delays.
• RAM usage drops to about 290.2 MB even with two separate user accounts signed in simultaneously.
• The app leverages GPUI, a GPU-accelerated UI framework for Rust, bypassing the heavy Chromium browser engine.

The previous Electron architecture inherited heavy multi-process mechanics from Chromium, resulting in high resource consumption. Even after minor performance patches, the old client typically idled around 1 to 2 gigabytes of RAM. The new architecture eliminates the frustrating startup screens and lengthy update checks by handling updates seamlessly in the background.

For rendering the interface, Discord opted for GPUI, a fast hybrid GPU-accelerated UI framework created by the makers of the Zed code editor, drawing directly on the GPU without bundling HTML. However, web technologies are still utilized where they make sense, such as system webviews for embedded YouTube videos and interactive activities, while web versions transition logic to WebAssembly.

Discord's successful transition away from Electron highlights a major turning point for desktop application development. While tech giants like Microsoft and Meta continue to rely on heavy web wrappers that consume massive amounts of system memory, Discord proves that chat apps can achieve native-like speed and efficiency without sacrificing features or security.