Niubash CLI
A native Bash-compatible shell written in Rust for Windows, Linux and macOS, running agent commands exactly as written.
- 268 ★ on the repository
- Last commit
- MIT
Broad access
Why this level
- Runs any shell command with user rights, including writing and deleting files.
Install
- Works in
Manual install
winget install --id Unixwin.NiubashThe first command of the Quick start section installs the Windows release through winget. Linux has an apt package and a portable archive.
Access and checks
How we reviewBroad accessThe tool can change data, run commands or handle secrets.
- Runs any shell command with user rights, including writing and deleting files.
This is third-party code. Review the repository files before installing.
What it does
Niubash is a shell with GNU Bash 5.3 semantics rewritten in Rust. On Windows a single `niu.exe` carries the language engine, the WinuxCmd set of Unix commands, a real git built from the git-for-windows sources and a plugin system. No WSL, virtual machine or POSIX emulation layer is needed. For agents the README explains how to make niu the default shell: agents launched from a niu session inherit it through the `SHELL` variable. The `--ec` flag accepts a whole command as a base64 string, so nested quotes, `$` and backslashes survive passing through several hosts. `niu --version` shows exact builds of the engine and the command layer, which helps agent logs.
Who it is for. Windows developers whose agents write Bash commands and stumble over Git Bash, MSYS2 or PowerShell.
Good fit when
- An agent on Windows emits Bash commands and nested quotes break along the way.
- You want a real git without the MSYS environment and extra launcher hops.
- The same shell script runs on Windows, Linux and macOS.
- Git Bash takes hundreds of megabytes and a small portable option is wanted.
Not a fit when
- A working WSL setup already exists and there is no reason to change shells.
- Scripts rely on GNU extensions that the project does not cover yet.
- You need a platform not covered in the README, for example full HarmonyOS support.
Example request
Run the tests in this project through niu and show the git log output for the last day.Limitations
Windows is the flagship platform, and the Linux and macOS builds use the tools of your system. Android support depends on Termux, and the honest state of each platform is described in the Platforms section of the README. The README lists known differences from GNU Bash, so read them before moving production scripts to niu. The license is MIT. The last commit is dated November 2026.
How to disable. On Windows remove the program through Apps & features or `winget uninstall Unixwin.Niubash`, on Linux run `sudo apt remove niubash`. Then restore the previous shell in the agent terminal profile.
FAQ
How do I install Niubash on Windows?
Run `winget install --id Unixwin.Niubash` or download the installer from the releases page. Administrator rights are not required, and PATH and a Windows Terminal profile are set up automatically.
How does niu differ from Git Bash?
Niu implements Bash 5.3 semantics natively without POSIX emulation and carries a real git built with MSVC. Git Bash runs on top of MSYS2 and rewrites paths heuristically.
What is the `--ec` flag for?
It takes a command as one base64 string, so nothing needs escaping. Intermediate hosts then cannot distort the agent command.
How do I make niu the shell for an agent?
Any agent launched from a niu session inherits `SHELL`. For other agents, `docs/src/agents.md` explains which shell each one uses and how to point it at niu.
Where is configuration stored?
On Windows in a single `~/.niubashrc` file in plain Bash syntax. An example sits in `.niubashrc.example`.
Discussion
No questions or reviews yet.
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README in short
The README compares niu with Git Bash, MSYS2 and Cygwin, lists the platforms and gives performance data. A separate section states known limitations.