Install any CLI tool unlimited times. Every instance is its own world.

Warren is a production-grade, rootless, zero-daemon CLI runtime. It lets you install and run unlimited, completely isolated instances of any CLI or TUI application on your Linux machine.

Like a rabbit warren, it creates a network of isolated tunnels—each self-contained yet sharing the same ground. Fast, rootless, and invisible infrastructure.

Why Warren?

Ever needed to log into two different GitHub accounts using the gh CLI? Or test a beta version of a tool without breaking your stable setup? Or maintain separate configurations for work and personal projects?

With Warren, you can:

warren dig gh --as gh-work
warren dig gh --as gh-personal

gh-work        # Logs into your company GitHub
gh-personal    # Logs into your personal GitHub

Both instances behave independently. They share the host machine but nothing else.

Non-Goals

Warren is not a container runtime (like Docker), a virtual machine, or a privilege escalation tool. It stays lightweight (single binary), rootless (no sudo ever), zero-daemon (no background processes), and incredibly fast (<50ms startup overhead).

Features

• Isolated Filesystems: Each instance gets its own home/, config/, cache/, data/, and tmp/ directories.
• Installer Rewriting: Automatically rewrites paths inside installation scripts on-the-fly to keep them contained.
• Rootless by Design: Will absolutely refuse to run as root.
• Universal Shell Support: Works seamlessly across Bash, Zsh, Fish, and Nushell.
• Zero Overhead: No daemons or containers. Just a thin, native bash launcher script.

Installation

Method 1: The One-Liner (Recommended)

Run the automated install script. This will download the latest binary and automatically configure your shell (bash, zsh, fish, or nushell).

curl -fsSL https://raw.githubusercontent.com/swadhinbiswas/warren/main/install.sh | bash

Method 2: Via Cargo (crates.io)

If you already have Rust installed, you can build and install Warren directly from crates.io:

cargo install warren-cli
warren shell install  # Sets up your PATH

Quick Start

1. Install a new instance from a remote script:

warren dig "curl -fsSL https://opencode.ai/install | bash" --as opencode-work

2. See what you've installed:

$ warren ls

  ALIAS            APP         VERSION    CREATED
  opencode-work    opencode    0.4.2      just now

3. Run your instance:

opencode-work --version
# or 
warren run opencode-work -- --version

4. Inspect an instance's isolated footprint:

warren inspect opencode-work

How it Works

Warren achieves total isolation without kernel namespaces or OverlayFS through three simple levers:

1. Intelligent Rewriting: When you install a tool via a bash script, Warren intercepts it. It scans for hardcoded paths (like /usr/local/bin or ~/.config) and rewrites them to point inside the instance's private directory (~/.warren/instances/<alias>).
2. Environment Injection: Warren generates a lightweight wrapper script in ~/.local/bin. When you run your alias, this script forcibly overrides $HOME, $XDG_CONFIG_HOME, $XDG_DATA_HOME, and $TMPDIR.
3. Execution: The target application boots up, entirely unaware that its "home directory" is actually a sandbox inside ~/.warren/.

Command Reference

Shell Support

Warren automatically detects your shell and configures your $PATH. It natively supports:

• Bash (~/.bashrc / ~/.bash_profile)
• Zsh (~/.zshrc)
• Fish (~/.config/fish/config.fish via fish_add_path)
• Nushell (env.nu via $env.PATH)

License

MIT License. See LICENSE for details.