Setting the Default Node Version with NVM

Introduction

Managing multiple versions of Node.js is a common necessity for developers working on various projects. Node Version Manager (NVM) is a tool that allows you to switch between different Node.js versions seamlessly, without affecting the entire system. One crucial aspect of using NVM efficiently is setting a default Node version that your environment will use whenever you start a new terminal session or project.

In this tutorial, we’ll explore how to set and manage the default Node version using NVM on Ubuntu with Zsh shell (though these steps are generally applicable across different shells and operating systems).

Understanding NVM

NVM (Node Version Manager) is an open-source tool for managing multiple active versions of Node.js. It allows developers to install, switch between, and manage various versions easily.

Basic NVM Commands:

• nvm list: Displays all installed Node.js versions.
• nvm use <version>: Switches the current session to a specific version.
• nvm install <version>: Installs a new Node.js version.
• nvm uninstall <version>: Removes an installed Node.js version.

Setting the Default Node Version

1. Installing NVM

Before setting a default node version, ensure you have NVM installed. You can install it using the following command:

curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.39.2/install.sh | bash

After installation, restart your terminal or run:

source ~/.zshrc

2. Listing Installed Node Versions

To view the versions of Node.js installed on your system, use:

nvm list

You will see a list similar to this:

v6.11.5
->       v9.0.0
system
default -> node (-> v9.0.0)
node -> stable (-> v9.0.0) (default)
stable -> 9.0 (-> v9.0.0) (default)

3. Setting a Default Node Version

To set the default version of Node.js, use the nvm alias command.

Setting to a Specific Version:

Suppose you have installed Node versions 6.11.5 and 9.0.0 and want to make 6.11.5 your default. Use the following command:

nvm alias default 6.11.5

This sets version 6.11.5 as the default.

Using Aliases for Flexibility:

• Default Specific Version: To always use a particular version, specify it like nvm alias default 6.11.5.
• Latest Node Release: Use nvm alias default node to set the latest release of Node.js as your default.
• Major Version Default: If you want the latest within a specific major version (e.g., Node 16), use nvm alias default 16.

4. Verifying and Using the Default

After setting the default version, verify it using:

nvm alias

You should see your default set like so:

default -> 6.11.5 (-> v6.11.5)

To use the default Node.js version in your current shell session:

nvm use default

5. Common Pitfalls and Solutions

• Version Does Not Exist: If you attempt to set a non-existent version as default, NVM will warn you. Ensure the version is installed first using nvm install <version>.

• Major Version Default: To set a major version as default without specifying a patch, use nvm alias default 6. This means it will always point to the latest in that major release.

Best Practices

1. Stay Updated: Regularly update NVM itself using its GitHub releases page for new features and improvements.
2. Use .nvmrc Files: In your project directories, use a .nvmrc file containing the version number (e.g., 6.11.5). This ensures consistent environment setup across different machines.

Conclusion

Managing Node.js versions with NVM is straightforward once you understand how to set and manage defaults effectively. By mastering these commands, you can ensure your development environment remains flexible yet stable as you switch between projects requiring different Node versions.