Anthropic's Claude Code CLI had its full TypeScript source exposed after a source map file was accidentally included in version 2.1.88 of its npm package. The 512,000-line codebase was archived to GitHub within hours. Anthropic called it a packaging error caused by human error. The leak revealed unreleased features, internal model codenames, and multi-agent orchestration architecture.

A 600-run benchmark by Ruby committer Yusuke Endoh tested Claude Code across 13 languages, implementing a simplified Git. Ruby, Python, and JavaScript were the fastest and cheapest, at $0.36- $0.39 per run. Statistically typed languages cost 1.4-2.6x more. Adding type checkers to dynamic languages imposed 1.6-3.2x slowdowns. Full dataset available on GitHub.