Karl the Intern Summer 2000 at Infinite Loop being sorted by different algorithms

From Apple Intern to AI Mentor: Resurrecting 25-Year-Old Apple Sample Code

Back to Infinite Loop Imagine taking a photo and watching a computer sort every single pixel by color. Some methods take many minutes, others finish in milliseconds. Twenty-five years ago I was an intern at Apple, reviving hundreds of sample code projects and writing new ones to help illustrate how to write programs and use various APIs for Mac OS X developers. Classic Mac developers were facing Unix under the hood with new concepts such as memory protection, preemptive multitasking, new threading models, a new windowing model, overall very different set of APIs. Sample code was by far the easiest way to introduce these concepts. My favorite creation I called PThreadSorts, a demo that visualized sorting algorithms by scrambling and sorting image pixels. This weekend, with Claude as my AI assistant, I brought it back from the dead. ...

August 20, 2025 · 16 min · Karl