Huck

huck

A bash-compatible shell written in Rust, working toward being a drop-in replacement for everyday interactive and scripting use. huck implements most of bash's surface — expansions, control flow, functions, arrays, job control, line editing, programmable completion — and verifies it against real bash: every feature ships with a design spec, an implementation plan, a test suite, and a **byte-identical bash-diff harness** that runs the same fragments through both shells and asserts identical output.

Real-world bar: huck sources a non-trivial `~/.bashrc` (bash-completion, git prompt, nvm, mise activation) and drives interactive tab completion against the system `bash-completion` package.

Installation

**Homebrew (macOS/Linux):**

brew install jdstanhope/huck/huck

**Debian/Ubuntu (.deb):**

curl -fsSL https://raw.githubusercontent.com/jdstanhope/huck/main/scripts/install.sh | sh
# or, manually:
sudo apt install ./huck__.deb

**From source:**

cargo install --git https://github.com/jdstanhope/huck huck

Status

Actively developed, one coherent feature at a time. Current scope:

• ~3,400 tests (unit + integration) and 160 bash-diff harnesses, all green; cargo clippy --all-targets clean.
• Command-substitution-heavy scripts run at near-bash speed: per-$() Shell clone is O(1) via copy-on-write (Rc + make_mut); 2000× $(true) after loading nvm: ~0.7 s vs ~46 s pre-fix; nvm ls wall-clock now matches bash.
• Sources ~/.bashrc-class startup files and the system bash-completion framework without errors.
• Known gaps and actionable divergences are tracked as GitHub issues labelled `divergence`; deliberate, kept-by-design divergences live in `docs/bash-divergences.md` — see Known differences from bash below for the summary.

The full feature history (every iteration's spec and plan) lives