Getting Started

Released (v0.17.0)Available in stable release v0.17.0.

notMyShell (NMSh) is a terminal frontend that operates over a persistent, real shell session (zsh, Bash, or Fish). Instead of replacing the shell or running commands as isolated subprocesses, NMSh orchestrates a hidden pseudo-terminal (PTY) running that shell.

Installation

Homebrew (macOS)

Homebrew is the recommended install method on macOS.

brew install raiseCatError/tap/nmsh
nmsh

To update, use brew upgrade raiseCatError/tap/nmsh.

Build from source (macOS, Linux, WSL 2)

You need:

• Node.js 22 or newer
• zsh (default), Bash 4.4+, or Fish

git clone https://github.com/raiseCatError/notMyShell.git
cd notMyShell
npm install
npm run build
npm link
nmsh

Note on GUI terminals: To start NMSh from a GUI terminal like Ghostty or Zed, use absolute paths so macOS PATH differences cannot break startup: command = direct:/absolute/path/to/node /absolute/path/to/nmsh. Never set nmsh as your system/login shell with chsh.

First Launch

When you first run nmsh, you will be greeted by Setup Cat. Setup Cat guides you through the initial customization, including choosing a layout (Bottom, Top, or Flow), a prompt style, and a theme.

If you skip setup or want to change it later, type /setup in the composer.

Switching Shells

NMSh uses a shared ShellAdapter for zsh, Bash, and Fish. To switch the shell of your current session, type:

/shell

To set the default shell for new sessions, go to /settings and navigate to the Sessions tab.