Oleksii Trekhleb writes JavaScript tutorials and visual demos on machine learning, genetic algorithms, image processing, and number representation.
HN commenters like his visual demos, such as the self-parking car, and find his content-aware image resizer a notable idea.
It is a very visual and entertaining visualization, I love it.
It inspired me to experiment with a genetic algorithm in "Self-parking car evolution":
https://trekhleb.dev/self-parking-car-evolution/
I can't believe this doesn't mention Image Seam Carving. Surprise this was never built into browsers.
https://trekhleb.dev/js-image-carver/