Windows 95 Setup: The Surprisingly Complex Story of a Tiny OS

This article reveals the hidden complexity of the Windows 95 setup program. To create a seemingly simple installer, the team had to build a miniature operating system from scratch within MS-DOS, including graphics libraries, a window manager, multilingual support, and even compatibility with Windows 3.1. They ultimately realized it was far more efficient to use the existing Windows 3.1 runtime, avoiding massive development efforts. The story highlights the importance of code reuse in software engineering and exposes the surprisingly complex nature of the Windows 95 setup program.