Universal NVM (@jchip/nvm)

A universal node.js version manager for Windows (no admin) and Unix.

- Install is simple with a PowerShell script on Windows, or a bash script on Unix.

- No admin required on Windows to install or use.

- A linked system wide version that can be changed any time.

- Change to any version independently in a terminal any time.

Table Of Contents

- Universal NVM (@jchip/nvm)
- Table Of Contents
- Installing Universal NVM on Windows using PowerShell
- Installing from github.com
- Installing from unpkg.com
- Installing from jsdelivr.net
- Windows 7 Updates
- Troubleshooting
- Running scripts disabled
- No PowerShell - Manual Install
- Installing Universal NVM on Unix
- Installing from github.com
- Installing from unpkg.com
- Installing from jsdelivr.net
- Shell Initialization on Unix
- Zsh (macOS default)
- Bash
- Usage
- Environments
- nvx - Execute with local node_modules
- Basic Usage
- Show Help
- Installing to PATH (macOS/Linux only)
- Install to User PATH (recommended)
- Install to System PATH (all users)
- How it Works
- Contributing and Release
- Development
- Release Process
- License

Installing Universal NVM on Windows using PowerShell

_You don't need admin rights to install or use_, only the permission to execute PowerShell scripts.

Tested on Windows 10, 8.1, and 7. Windows 7 requires PowerShell updates, see update instructions.

To install, start a Windows PowerShell and copy and paste one of the scripts below into the shell terminal and press enter.

- This will install nvm and current LTS Node.js (v12.13.0) to directory nvm under your home specified by $Env:USERPROFILE.

- If you want to install this under another directory, then set it with the param -nvmhome.

- If you don't set it, then $Env:NVM_HOME will be checked, and if non-existent, then a Directory Browser dialog will be opened for you to create and choose a directory.

Video Demo of upgrading Windows 7 to PowerShell 5.1 and then installing this

You can retrieve the install script from multiple sources. Listed below are three options for you to choose from in case one of them is down.

$3

Retrieve install script from github.com directly:

``powershell
cd $Env:USERPROFILE;
Invoke-WebRequest https://raw.githubusercontent.com/jchip/nvm/v1.9.0/install.ps1 -OutFile install.ps1;
.\install.ps1 -nvmhome $Env:USERPROFILE\nvm;
del install.ps1
`

$3

Retrieve install script from unpkg.com:

`powershell
cd $Env:USERPROFILE;
Invoke-WebRequest https://unpkg.com/@jchip/nvm@1.9.0/install.ps1 -OutFile install.ps1;
.\install.ps1 -nvmhome $Env:USERPROFILE\nvm;
del install.ps1
`

$3

Retrieve install script from jsdelivr.net:

`powershell
cd $Env:USERPROFILE;
Invoke-WebRequest https://cdn.jsdelivr.net/npm/@jchip/nvm@1.9.0/install.ps1 -OutFile install.ps1;
.\install.ps1 -nvmhome $Env:USERPROFILE\nvm;
del install.ps1
`

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PowerShell version 4+ is required.

For Windows 7, you can update it to version 5.1 with the following instructions:

1. Go to
2. Click Red Download button
3. Download Win7AndW2K8R2-KB3191566-x64.zip or Win7-KB3191566-x86.zip for 32-bit
4. Unzip the file
5. Run the package Win7AndW2K8R2-KB3191566-x64.msu or Win7-KB3191566-x86.msu for 32-bit

After it's completed and rebooted, launch PowerShell and type $PSVersionTable to check.

> PSVersion should be something like 5.1.#####.####

Video Demo of upgrading Windows 7 to PowerShell 5.1 and then installing this

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#### Running scripts disabled

If you get the error:

> install.ps1 cannot be loaded because running scripts is disabled on this system.

Then you need to set execution policy for PowerShell to RemoteSigned with the command:

`powershell
Set-ExecutionPolicy -Scope CurrentUser -ExecutionPolicy RemoteSigned
`

See this StackOverflow question for details.

You need to keep this policy if you want to use nvm in PowerShell to switch node.js versions.

#### No PowerShell - Manual Install

If for some reason you absolutely can't have PowerShell or permission to install from it, then you can try to manually install following these steps:

1. Download the package zip file from https://github.com/jchip/nvm/archive/v1.9.0/.zip
1. Extract this file to your home directory. You will get a new directory nvm-1.9.0.
2. Rename it to nvm, for example: C:\Users\\nvm
2. Download the zipfile https://nodejs.org/dist/v20.12.1/node-v20.12.1-win-x64.zip
1. Extract this file to C:\Users\\nvm. You will get a new directory node-v20.12.1-win-x64
2. Move node.exe from that directory into C:\Users\\nvm
3. (optional) You can delete the directory after if you want.
3. Open RegEdit.exe, in HKEY_CURRENT_USER/Environment
1. Add the following entries
1. NVM_HOME -> C:\Users\\nvm
2. NVM_LINK -> C:\Users\\nvm\nodejs\bin
2. Append the following to the entry Path
1. ;C:\Users\\nvm\bin;C:\users\\nvm\nodejs\bin
4. Open Command Prompt, and run nvm install lts, note the version installed, and then nvm link .

_Make sure to replace above with your actual user name_.

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If you want to use Universal NVM with Git Bash after installing on Windows via PowerShell:

1. First install nvm using PowerShell (see instructions above)
2. Open Git Bash
3. Run the setup script:
`bash
$NVM_HOME/bin/nvm-setup.sh
`
4. Restart Git Bash or run:
`bash
source ~/.bashrc
`

Now you can use nvm commands in Git Bash just like on Unix systems.

Installing Universal NVM on Unix

Because this is implemented in node.js, it happens to work on Unix also. It just need a different install script using bash.

To retrieve and run the install script, provided below are three options for you to choose from in case one of them is down.

Please pick one and then copy and paste it into a bash terminal to run.

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Retrieve the install script from github.com:

Using cURL and the install script:

`bash
export NVM_HOME=~/nvm; curl -o- https://raw.githubusercontent.com/jchip/nvm/v1.9.0/install.sh | bash
`

or wget:

`bash
export NVM_HOME=~/nvm; wget -qO- https://raw.githubusercontent.com/jchip/nvm/v1.9.0/install.sh | bash
`

$3

Retrieve the install script from unpkg.com:

Using cURL and the install script:

`bash
export NVM_HOME=~/nvm; curl -o- https://unpkg.com/@jchip/nvm@1.9.0/install.sh | bash
`

or wget:

`bash
export NVM_HOME=~/nvm; wget -qO- https://unpkg.com/@jchip/nvm@1.9.0/install.sh | bash
`

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Retrieve the install script from jsdelivr.net:

Using cURL and the install script:

`bash
export NVM_HOME=~/nvm; curl -o- https://cdn.jsdelivr.net/npm/@jchip/nvm@1.9.0/install.sh | bash
`

or wget:

`bash
export NVM_HOME=~/nvm; wget -qO- https://cdn.jsdelivr.net/npm/@jchip/nvm@1.9.0/install.sh | bash
`

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The Universal NVM installation automatically updates your shell profile files to initialize nvm. The behavior differs between zsh and bash:

#### Zsh (macOS default)

For zsh users, the installer updates both .zshenv and .zshrc:

- .zshenv: Sourced for ALL shells (interactive and non-interactive)
- .zshrc: Sourced for interactive shells only

This means:
- ✅ Terminal sessions have nvm available
- ✅ Non-interactive scripts have nvm available
- ✅ GUI applications (like VS Code) have nvm available (when combined with nvx --install-to-user)

#### Bash

For bash users, the installer updates .bashrc or .bash_profile:

- .bash_profile: Sourced for login shells (macOS default)
- .bashrc: Sourced for interactive non-login shells (Linux default)
- Non-interactive shells: NOT sourced by default

This means:
- ✅ Terminal sessions have nvm available
- ❌ Non-interactive bash scripts do NOT have nvm by default

Using nvm in bash scripts:

If you need nvm in a bash script, you have three options:

1. Source the profile explicitly in your script:
`bash
#!/bin/bash
source ~/.bashrc
node --version
`

2. Use a login shell with the shebang:
`bash
#!/bin/bash -l
node --version
`

3. Set BASH_ENV to automatically source a file for non-interactive shells:
`bash
export BASH_ENV=~/.bashrc
`

You can add this to your .bash_profile to make it permanent, but be aware this will affect all bash scripts system-wide.

Note: This is standard bash behavior by design - non-interactive shells have a minimal environment for performance and predictability.

Usage

`
Usage: nvm [options]

Commands:
nvm install install the given version of Node.js
nvm uninstall uninstall the given version of Node.js
nvm use use the given version of Node.js in current shell
nvm auto-use [action] automatically use version from .nvmrc, .node-version,
or package.json
nvm auto-use enable [--cd] - enable automatic switching on cd
--cd: use cd wrapper mode (more efficient, only triggers on cd command)
nvm auto-use disable - disable automatic switching
nvm stop undo effects of nvm in current shell
[aliases: unuse]
nvm link permanently link the version of Node.js as default
nvm unlink permanently unlink the default version
nvm ls list all the installed Node.js versions
nvm ls-remote list remote versions available for install
nvm cleanup remove stale local caches
nvm postinstall [version]
Invoke custom post install script for the given version
nvm init-env
(windows) Generate cmd file to initialize env for nvm
nvm undo-env (windows) Generate cmd file to undo env for nvm

Options:
--proxy, -p Set network proxy URL [string]
--verifyssl, --ssl, --no-ssl Turn on/off verify SSL certificate
[boolean] [default: true]
--corepack, --no-corepack Enable corepack after installation
[boolean]
--latest Match latest version to uninstall
--version, -V, -v Show version number
--help, -?, -h Show help. Add a command to show its help
[string]

Error: No command given

envs:

NVM_PROXY - set proxy URL
HTTP_PROXY - fallback proxy for HTTP requests
HTTPS_PROXY - fallback proxy for HTTPS requests
NVM_VERIFY_SSL - (true/false) turn on/off SSL certificate verification (default: true)
NVM_COREPACK_ENABLED - (true/false) enable corepack on install (default: false)

Proxy priority: -p flag > NVM_PROXY > HTTPS_PROXY > HTTP_PROXY

Examples:

nvm install lts
nvm install latest
nvm install 20 --corepack
nvm use 20
nvm uninstall 22.3

doc: https://www.npmjs.com/package/@jchip/nvm

`

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Universal NVM can automatically switch Node.js versions when you change directories. When enabled, it will check for .nvmrc, .node-version, or package.json files and automatically switch to the specified version.

Quick Start:

`bash


Enable automatic switching (modifies your shell profile)

nvm auto-use enable

Enable with cd wrapper mode (more efficient, recommended)

nvm auto-use enable --cd

Disable automatic switching

nvm auto-use disable

Manually switch to version specified in current directory

nvm auto-use
`

Two modes available:

Auto-use offers two different modes for triggering version switches:

1. Prompt-based mode (default) - Runs on every prompt
- ✅ Catches ALL directory changes (cd, pushd, GUI navigation, terminal opening)
- ⚠️ Slightly more overhead (runs every time you press Enter)
- Best for: Ensuring you never miss a version switch

2. cd wrapper mode (--cd flag) - Runs only on cd commands
- ✅ More efficient (only runs when you actually change directories)
- ✅ Cleaner (direct cause and effect)
- ⚠️ Misses directory changes from pushd, popd, or terminal opening in new location
- Best for: Performance-conscious users who primarily use cd

Which mode to choose:

`bash


Use prompt-based if you want comprehensive coverage

nvm auto-use enable

Use cd wrapper if you prefer efficiency

nvm auto-use enable --cd
`

Note for Zsh users: Zsh always uses the optimal chpwd_functions mechanism (triggers only on actual directory change), so the --cd flag has no effect. Zsh users automatically get the best of both worlds!

What nvm auto-use enable does:

- Bash/Zsh: Adds auto-use setup to ~/.bashrc, ~/.bash_profile, or ~/.zshrc
- PowerShell: Adds auto-use setup to your PowerShell profile ($PROFILE)
- Automatically detects your shell and modifies the correct profile file

After enabling, restart your terminal or source your profile:
`bash
source ~/.bashrc # Bash on Linux
source ~/.bash_profile # Bash on macOS
source ~/.zshrc # Zsh
. $PROFILE # PowerShell
`

How it works:
- When you change directories, auto-use checks for version files (.nvmrc, .node-version, or package.json)
- If found and a different version is needed, it switches and shows: Using node v20.10.0 (auto-use from .nvmrc)
- If the version is already active, it does nothing (fast and silent!)
- If the version isn't installed, it shows an error once per shell session: Version 16.0.0 from .nvmrc not installed
- The error is only shown once - subsequent cd commands won't repeat the same error
- This helps you know which version to install without spamming your terminal
- If no version file is found, it does nothing (no error messages)

Manual vs Automatic invocation:
- Automatic (via cd/prompt hooks): Uses --silent flag to suppress "no version file found" errors
- Manual (typing nvm auto-use): Shows all messages including "no version file found" errors

When auto-use is triggered automatically by changing directories, you'll see:
- ✓ Version switch messages (always shown)
- ✓ "Version not installed" errors (shown once per shell session)
- ✗ "No version file found" errors (suppressed)

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When you run nvm use or nvm auto-use without specifying a version, Universal NVM will automatically look for a version specification in the current directory.

Supported sources (in priority order):

1. .nvmrc - nvm-specific version file (checked first)
2. .node-version - Universal Node.js version file (checked if .nvmrc not found)
3. package.json → engines.node - Fallback to package.json engines field (checked if no version files exist)

Usage:

`bash


Option 1: Create a .nvmrc file

echo "20.10.0" > .nvmrc

Option 2: Create a .node-version file

echo "20.10.0" > .node-version

Option 3: Use package.json engines.node

cat > package.json << EOF
{
"name": "my-project",
"engines": {
"node": ">=18.0.0"
}
}
EOF

Use the version specified in any of these sources

nvm use

Output varies based on source:

- Read version 20.10.0 from .nvmrc

- Read version 20.10.0 from .node-version

- Read node requirement ">=18.0.0" from package.json

Found installed version v20.10.0 matching ">=18.0.0"

`

File format:

.nvmrc and .node-version files should contain a plain text version number on a single line:

`
20.10.0
`

Or with the v prefix:

`
v20.10.0
`

Semver ranges:

All version sources support semantic versioning (semver) ranges. Universal NVM will automatically select the highest installed version that satisfies the requirement.

In .nvmrc or .node-version:

`
>=18.0.0
`

`
^20.0.0
`

`
20
`

In package.json engines.node:

The engines.node field supports the same semver syntax:

`json
{
"engines": {
"node": ">=18.0.0" // Any version 18 or higher
}
}
`

`json
{
"engines": {
"node": "^20.0.0" // Latest 20.x version
}
}
`

`json
{
"engines": {
"node": ">=18.0.0 <21.0.0" // Version 18 or 20, but not 21+
}
}
`

If no installed version matches a semver range, you'll see a helpful error message suggesting which version to install.

Priority when multiple sources exist:

If multiple version sources exist in the same directory, Universal NVM will prefer them in this order:

`bash


With all three present

$ cat .nvmrc
18.20.0

$ cat .node-version
20.10.0

$ cat package.json
{
"engines": { "node": ">=16.0.0" }
}

$ nvm use

Output: Read version 18.20.0 from .nvmrc

.node-version and package.json are ignored

`

Benefits of each approach:

.nvmrc - Best for teams using traditional nvm:
- Standard for nvm users
- Supports both exact versions and semver ranges
- Most familiar to developers using nvm

.node-version - Best for cross-tool compatibility:
- Universal standard for Node.js version specification
- Supports both exact versions and semver ranges
- Makes your project more portable

package.json engines.node - Best for existing projects:
- Already part of Node.js ecosystem
- Supports semver ranges for flexibility
- Single source of truth (no separate version file needed)
- Automatically used as fallback if no .nvmrc or .node-version exists

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These env flags can be set:

| name | values | description |
| ---------------- | -------------- | ------------------------------------------- |
| NVM_PROXY | string | An URL to a network proxy (highest priority) |
| https_proxy | string | An URL to a network proxy for HTTPS (lowercase, npm convention) |
| HTTPS_PROXY | string | An URL to a network proxy for HTTPS (uppercase) |
| http_proxy | string | An URL to a network proxy for HTTP (lowercase, npm convention) |
| HTTP_PROXY | string | An URL to a network proxy for HTTP (uppercase) |
| NVM_VERIFY_SSL | true/false | Controls SSL certificate verification (default: true) |
| NVM_COREPACK_ENABLED | true/false | Enable corepack after installation (default: false) |

Proxy Priority:
1. Command-line -p flag (highest priority)
2. NVM_PROXY (overrides all protocol-specific proxies)
3. Protocol-specific proxy (matches URL being fetched):
- For HTTPS URLs: https_proxy → HTTPS_PROXY → http_proxy → HTTP_PROXY
- For HTTP URLs: http_proxy → HTTP_PROXY

Following npm convention, lowercase environment variables are checked first, then uppercase.

#### SSL Certificate Verification (NVM_VERIFY_SSL)

By default, Universal NVM verifies SSL/TLS certificates when downloading Node.js from distribution servers. This ensures you're downloading from a trusted source.

When to disable SSL verification:

You may need to set NVM_VERIFY_SSL=false in these scenarios:

- Corporate proxies with SSL inspection - Your company's network intercepts HTTPS connections with self-signed certificates
- Internal mirrors - You're using an internal Node.js mirror with self-signed certificates
- Development environments - Testing with local servers using self-signed certificates

How to use:

`bash


Disable SSL verification via environment variable (Unix/macOS)

export NVM_VERIFY_SSL=false
nvm install lts

Disable SSL verification via environment variable (Windows PowerShell)

$Env:NVM_VERIFY_SSL = "false"
nvm install lts

Disable SSL verification via command-line flag

nvm install lts --no-ssl
`

Security Warning: Disabling SSL verification makes you vulnerable to man-in-the-middle attacks. Only disable it when you trust your network and understand the risks. Re-enable verification after completing your task:

`bash


Re-enable SSL verification (Unix/macOS)

export NVM_VERIFY_SSL=true

Re-enable SSL verification (Windows PowerShell)

$Env:NVM_VERIFY_SSL = "true"
`

#### Corepack Support (NVM_COREPACK_ENABLED)

Corepack is a built-in Node.js feature (available since v16.9.0) that manages package managers like Yarn and pnpm. It allows you to use the exact package manager version specified in your project's package.json without manually installing them.

When to enable corepack:

- Using Yarn or pnpm - Your project uses Yarn or pnpm instead of npm
- Version consistency - You want to ensure everyone on your team uses the same package manager version
- Modern projects - You're working with projects that specify packageManager in package.json

How to use:

`bash


Enable corepack via environment variable (Unix/macOS)

export NVM_COREPACK_ENABLED=true
nvm install lts

Enable corepack via environment variable (Windows PowerShell)

$Env:NVM_COREPACK_ENABLED = "true"
nvm install lts

Enable corepack via command-line flag (one-time)

nvm install 20 --corepack

Disable corepack for a specific installation

nvm install 18 --no-corepack
`

What corepack does:

After installing Node.js, Universal NVM will automatically run corepack enable, which:
- Makes yarn and pnpm commands available
- Respects the packageManager field in your package.json
- Automatically uses the correct package manager version for your project

Example package.json with packageManager:

`json
{
"name": "my-project",
"packageManager": "pnpm@9.1.0",
"dependencies": {
"express": "^4.18.0"
}
}
`

With corepack enabled, running pnpm install will automatically use pnpm version 9.1.0, even if you don't have it installed globally.

Note: If corepack fails to enable (e.g., on Node.js versions before v16.9.0), Universal NVM will show a warning but will not fail the installation. You can manually enable it later with:

`bash
corepack enable
`

Priority: --corepack flag > NVM_COREPACK_ENABLED env var > default (false)

nvx - Execute with local node_modules

The nvx command allows you to run commands from your local node_modules/.bin directory without needing to specify the full path. It only runs locally installed packages, making it fast and predictable for running project-specific tools.

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`bash


Run eslint from local node_modules

nvx eslint src/

Run prettier from local node_modules

nvx prettier --write .

Run any locally installed CLI tool

nvx jest --watch
`

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`bash
nvx --help


or


nvx -h
`

$3

On macOS and Linux, you can optionally add the Universal NVM bin directory to your system PATH to make nvm commands available in GUI applications (like VS Code).

#### Install to User PATH (recommended)

This adds Universal NVM to your user's PATH. Works with GUI applications and doesn't require sudo:

macOS:
`bash
nvx --install-to-user


Log out and log back in for changes to take effect


`

Linux:
`bash
nvx --install-to-user


Log out and log back in for changes to take effect


`

#### Install to System PATH (all users)

This adds Universal NVM to the system-wide PATH for all users. Requires sudo:

macOS:
`bash
sudo nvx --install-to-system


Restart your terminal for changes to take effect


`

Linux:
`bash
sudo nvx --install-to-system


Log out and log back in for changes to take effect


`

Note for Windows users: On Windows, the installation script automatically adds both %NVM_HOME%\bin and %NVM_LINK% to your user PATH in the Windows registry. This makes Universal NVM, node, and npm immediately available to all applications (terminal, GUI apps like VS Code, etc.) without needing to run any additional commands. The nvx --install-to-user and nvx --install-to-system commands are therefore not needed on Windows.

#### How it Works

The nvx --install-to-user command uses platform-specific mechanisms to make Universal NVM available to GUI applications:

macOS:

Creates a LaunchAgent at ~/Library/LaunchAgents/com.jchip.universal-nvm.plist that runs at login to set environment variables for the user session. This makes Universal NVM available to:
- All GUI applications (VS Code, editors, etc.)
- Terminal windows
- Background processes

The LaunchAgent adds both paths to your environment:
- ~/nvm/bin - nvm commands (nvm, nvx)
- ~/nvm/nodejs/bin - Node.js executables (node, npm) - only available after running nvm link

Linux:

Creates a systemd user environment file at ~/.config/environment.d/10-jchip-universal-nvm.conf. This file is read by systemd-based desktop environments at login and makes Universal NVM available to:
- All GUI applications launched from the desktop
- Applications started by systemd user services
- Any process in your user session

The environment file adds both paths:
- ~/nvm/bin - nvm commands (nvm, nvx)
- ~/nvm/nodejs/bin - Node.js executables (node, npm) - only available after running nvm link

Important: The ~/nvm/nodejs/bin directory is a symlink created by nvm link that points to the default Node.js version. You must run nvm link to set up a default Node.js version before GUI applications can access node and npm. The install script does this automatically.

Note: On Linux systems not using systemd, this feature may not work. In that case, you can manually add the paths to your ~/.profile or consult your distribution's documentation for setting user environment variables.

Contributing and Release

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1. Clone the repository
2. Install fyn globally: npm install -g fyn
3. Install dependencies: fyn install
4. Make your changes
5. Run tests: fyn run test
6. Run tests in watch mode: fyn run test:watch
7. Run tests with coverage: fyn run test:coverage
8. Test your changes on the target platform(s)

Testing:

This project uses Vitest for testing. The test suite includes:
- Unit tests for proxy configuration and priority logic
- Integration tests with a custom test proxy server
- Tests for malformed requests and error handling
- Real-world tests with nodejs.org URLs

$3

This project uses xrun for versioning and releasing. Do not use npm version or npm publish directly.

1. Update CHANGELOG.md - Add a new entry at the top with the version and date:
`markdown
## X.Y.Z MMM DD, YYYY

- feat: description of new feature
- fix: description of bug fix
`

2. Bump version - Choose the appropriate version bump:
`bash
xrun version --patch # Bug fixes (1.7.0 -> 1.7.1)
xrun version --minor # New features (1.7.0 -> 1.8.0)
xrun version --major # Breaking changes (1.7.0 -> 2.0.0)
`

3. Release - Publish to npm:
`bash
xrun release
``

License

MIT