Karpathy built a better YouTube with Claude in two hours
Andrej Karpathy just built HackerTube, an alternative YouTube recommender, in about two hours using Claude Opus 5.5. Frustrated by YouTube's noisy recommendations, he used Claude Code to filter 43 million Hacker News comments down to 6,454 heavily recommended videos with no login required. Why it matters: It proves how frontier AI lets solo developers ship custom, algorithm-free tools in a single afternoon.