The developer under the nickname Mayuki published ReProgman – a clone of the program manager from Windows 3.1, compiled using Claude Code. The name refers to progman.exe, the main shell for operating systems of the early 90s, which was supplanted by Explorer in Windows 95 in 1995.
The first working version appeared in about an hour of machine code generation. According to the developer, the result was “quite decent”, but required improvement to eliminate shortcomings in the behavior of the interface.
The creator of the project himself treats the creation with irony and does not promise long-term pleasure from use.
I asked Claude to create a clone of the Program Manager from Windows 3.1. I think you can be nostalgic with him for about thirty seconds.
Pre-built end-user builds are 12 to 16 MB in size and require no installation. The program runs on both Windows 11 and macOS with Apple Silicon chips, making it a convenient way to browse the files and applications of a modern system through an interface from thirty years ago.
To build and run it yourself, you will need .NET SDK version 10.0 or later. Source code published on GitHubso anyone can add their own functions to the shell.
Interestingly, progman.exe remained in Windows for a long time as an emergency tool. Up until Windows XP, users could use the registry to designate the program manager as the main shell if explorer.exe was damaged by a virus, and get a working graphical interface for running anti-virus utilities.
