Shannon

A poly-shell built on nushell, with seamless bash compatibility via brush. Shift+Tab to switch between nushell and bash.

Named after Claude Shannon, the father of information theory.

The Idea

Nushell is powerful but the world runs on bash. Shannon gives you both — press Shift+Tab to switch between nushell and bash. Environment variables and working directory sync automatically.

[nu] ~/project > ls | where size > 1mb
...
[nu] ~/project > <Shift+Tab>

[brush] ~/project > grep -r "TODO" src/ && echo "done"
...
[brush] ~/project > <Shift+Tab>

[nu] ~/project >

Features

Nushell at the Core

Shannon IS nushell — you get all nushell features out of the box:

• Structured data (tables, records, lists)
• Powerful pipelines (ls | where size > 1mb | sort-by modified)
• Job control (Ctrl+Z, job unfreeze)
• Native completions, multiline editing, plugins
• Hooks, keybindings, themes — all configurable via config.nu

Bash Compatibility

• Shift+Tab to switch to [brush] mode for bash commands
• Bash syntax highlighting (tree-sitter-bash, Tokyo Night colors)
• Environment variables sync between nushell and bash automatically
• env.sh for bash-style setup (PATH, API keys) — follow any tutorial that says "add this to your .bashrc"

Environment Sync

• Environment variables, cwd, and exit code synchronized across mode switches
• Set export FOO=bar in bash, switch to nushell — $env.FOO works
• Set $env.BAZ = "qux" in nushell, switch to bash — echo $BAZ works
• PATH and other typed env vars converted automatically via ENV_CONVERSIONS

Configuration

Shannon uses ~/.config/shannon/ (respects XDG_CONFIG_HOME):

No config files are required — shannon works out of the box.

Installation

cargo install shannonshell

Or build from source:

git clone --recursive https://github.com/shannonshell/shannon.git
cd shannon/shannon
cargo build --release

Note: --recursive is needed to fetch the nushell, brush, and reedline submodules.

License

MIT