Luish

Luish is a POSIX shell rewritten in Rust: the speed of dash with the interactive feel of zsh. It runs the author's bash scripts, matches dash/zsh output and exit status across hundreds of test scripts, and benchmarks 5–6x faster than bash/zsh on scripts while feeling tens of milliseconds more responsive interactively.

For daily use it borrows what makes zsh good: autosuggestions, TAB completion for ~230 commands, advanced globbing, vared, and it reads zsh's own histfile in zsh's format. Configuration is modern: options in TOML, plugins as a builtin feature fetched from git with a lockfile pinning versions. A standout is SSH mode — luish --ssh HOST gives you a local shell that stays responsive even when the server is on the other side of the planet, because completion menus render locally while commands run remotely.

The author, Luis Pedro Coelho, documents the whole experiment in a Substack essay titled "Luish: a vibe-coded shell that is better than bash or zsh" (2026-10-10): "I should just ask Claude to reimplement zsh in Rust." / "A few million tokens, 301 commits, and about 50,000 lines of Rust later, luish v0.6.0 is here." / "Every time I hit a failure, I ask Claude to add the missing functionality." Notably, Claude recommended Rhai — a language the author had never heard of — as the extension language, and it stuck. 2 stars on GitHub, pushed 2026-10-23; it is already the author's daily-driver shell. This is a command-line shell, so the demo link points at the repository.