ruster-env Ashok S K

cli cmd dotenv env environment-variables powershell rust

Use this command to install ruster-env:

winget install --id=AshokSK.ruster-env -e

ruster-env injects variables directly into your current session—just like source .env on Linux.

ruster-env

> Bend the environment to your will.

A blazingly fast, session-persistent environment variable manager built specifically for Windows (PowerShell & CMD).

ruster-env injects variables directly into your current terminal session, making them available for every subsequent command you run—just like source .env on Linux.

Features

Session Persistence: Variables stay loaded until you close the terminal.
Windows First: Native support for PowerShell and Command Prompt.
Safety Rails: --no-overwrite protects your system PATH and other critical variables.
Smart Interpolation: Supports variable expansion (e.g., URL=${HOST}:${PORT}).
Clean Unload: One command to wipe project variables without restarting your shell.
Zero Dependencies: Single binary, no Python/Node.js required.

Installation

Method 1: Winget (Recommended)

The easiest way to install is via the Windows Package Manager.

winget install ruster-env

Method 2: Manual (ZIP)

Download the latest ruster-env-windows-x64.zip from the Releases page.
Extract the files (ruster-core.exe and ruster-env.cmd) into a folder.
Add that folder to your System PATH.

Shell Setup

If you installed via Winget or added the Manual folder to PATH, CMD users are ready to go. PowerShell users need a one-time profile update.

PowerShell

Run the init command to get the setup script for your specific installation path:
```
ruster-env init --shell powershell
```

Copy the output command. It will appear as follows:

Invoke-Expression (&amp; "C:\Path\To\ruster-core.exe" init --shell wershell | Out-String)

Open your PowerShell profile:
```
notepad $PROFILE
```
Paste the copied command into the file and save it.
Restart PowerShell.

> [!TIP]
> Alternatively, run the copied command in your current powershell session to start using it immediately.

Command Prompt (CMD)

No extra setup required if the folder is in your PATH. The ruster-env.cmd wrapper handles everything automatically.

Usage

1. Load Variables

Injects variables from .env into your current session.

ruster-env load

Result: API_KEY is now available in your shell.
Options:
--verbose: See exactly what is being set.
--no-overwrite: Skips variables that already exist in your system (e.g., prevents hijacking USERNAME).

2. Set / Unset Single Variables

Quickly add or remove a single variable for the current session.

# Set a variable
ruster-env set DATA=Production

# Remove a variable
ruster-env unset DATA

3. Show Variables

Checks what is actually live in your system.

ruster-env show

List Mode: Prints all active system variables (hides internal Windows vars like =::).

Single Mode: Prints just the value (perfect for scripts).

# Copy DB URL to clipboard
ruster-env show DB_URL | clip

4. Run (Ephemeral)

Runs a single command with variables loaded, without modifying your current shell.

# Run a command with variables loaded from .env.test file (default=.env) isolated to that process

&gt; ruster-env run --path .env.test -- python -c "import os; print(os.environ['WELCOME_MSG'])"

Hello World!

# Verify the variable did NOT leak into the current session

&gt; ruster-env show WELCOME_MSG

Error: Variable 'WELCOME_MSG' is not set in the current environment.

5. Unload

Removes variables defined in your .env file from the session.

ruster-env unload

.env Syntax

ruster-env supports a robust syntax superset:

# Comments are supported
PORT=8080
HOST=localhost

# Quotes are stripped automatically
SECRET_KEY="super_secret_value"
SINGLE_QUOTES='works_too'

# Interpolation (References other variables)
# Order matters! Define base vars first.
DATABASE_URL=postgres://${HOST}:${PORT}/mydb