fzhiyu1/improv-os

ImprovOS is a web-based desktop that looks and behaves like macOS, with one unusual property: there are no pre-installed applications. When you click an icon in the Dock to open a calculator, the calculator does not open from storage. Instead, an AI model writes the calculator from scratch in about 2 to 3 seconds, and the code streams to your screen live as it is generated. Every time you open the same app, a different version is created. The core idea is that nothing is ever the same twice. The Spotlight search bar works the same way. You can type anything: "Russian Tetris," "cello," or "fish detector," and the AI generates a working web application for that description on the spot. Apps that have been generated before can be cached for instant reopening, and there is a dice button to regenerate a fresh version. There are two generation modes. The fast track produces a self-contained HTML page in 2 to 3 seconds. The slow track runs a longer AI agent loop that writes files, runs checks on its own output, and iterates, taking 16 to 27 seconds but producing more complete results. Generated apps can call a small set of provided APIs to fetch real data or make HTTP requests. Self-hosting requires Node.js 18 or later and an Anthropic API key. There are no npm dependencies for the server. The shell of the desktop (the Dock, menu bar, window management, and Spotlight) is written by hand in plain JavaScript and CSS with no framework. The README is written in Chinese. The project is MIT licensed.