The original 1996 Windows Task Manager author rebuilt it with AI in 3.5 hours

Dave Plummer, the former Microsoft engineer who wrote the original 1996 Windows Task Manager, has released new Windows, Mac, and Linux versions built with an AI coding tool, and it took the first pass roughly three and a half hours from a 107-page specification.

Plummer picked Task Manager specifically as a real-world test of whether AI-assisted coding could produce something useful rather than what he called "slop." His verdict, in his own words: "it depends on what you ask for, largely! And what you test and instrument." He compared the process to working with "a very ambitious and precocious intern," one that occasionally balked, mid-build, thinking it was being asked to do security work.

The result goes well beyond a bare process-killer. It exposes more system metrics than Microsoft's version, supports customizable themes down to a retro amber-and-green terminal look, and runs roughly half the size and memory footprint of the built-in Windows Task Manager, according to Plummer's own testing.

The build choice worth noting for anyone doing similar cross-platform work: Plummer skipped Electron in favor of native UI code per platform, Swift on Mac, Direct2D on Windows, Qt on Linux, specifically because a task manager needs game-like response times. He said the biggest surprise was how close the three versions ended up looking despite the platform differences.

The app is currently proprietary and pre-release, with a paid Pro tier planned; pricing hasn't been set yet. It's a small, concrete data point on a real 2026 question every practitioner is running their own version of: for a well-specified, well-tested build, how much of the work an AI coding agent can actually carry alone.