Install NVM

Different projects often require different versions of Node.js. NVM (Node Version Manager) makes it easy to install, manage, and switch between multiple Node versions on your machine, ensuring you can work on any project without version conflicts.

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What is NVM?

NVM (Node Version Manager) is a powerful tool that allows you to easily install and manage multiple versions of Node.js on your system.

We use NVM because it:

• Allows switching between Node.js versions with simple commands
• Enables working on projects with different Node requirements
• Prevents version conflicts across projects
• Makes it easy to test code on different Node versions
• Doesn’t require administrator/root privileges for Node installations
• Keeps your system clean with isolated Node installations

Download it

Download NVM from their Github Repository

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How to Install NVM

01. Open Your Terminal

Launch your terminal application.

02. Run the Installation Script

Execute the following curl command to download and install NVM:

curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.39.3/install.sh | bash

This will download and run the NVM installation script.

03. Verify Installation

To verify the installation, run:

command -v nvm

If you see nvm as output, the installation was successful.

04. Fix Developer Tools Error (macOS only)

You might see an error: “nvm xcrun error invalid active developer path.”

To solve this, install Xcode Command Line Tools:

xcode-select --install

05. Check NVM Version

After completing the previous steps, verify NVM is working:

nvm -v

You should see the version number (e.g., 0.39.3).

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Fix: NVM Not Loading Automatically in Terminal

Sometimes after installing NVM, you may notice that it’s not available in new terminal sessions, even though the installation completed successfully.

This usually happens because the installation script failed to correctly update your shell configuration file (.zshrc or .bashrc).

Why This Happens

During installation, NVM attempts to append the necessary environment variables to your shell config file. However, depending on:

• Your shell (zsh, bash, etc.)
• Custom configurations or permission issues
• Using tools like Oh My Zsh or custom terminal environments

…the required lines might not be added automatically, or may be placed incorrectly.

The Fix

You need to manually add the required lines to your shell configuration file.

For Zsh Users (default on macOS)

Edit your .zshrc:

nano ~/.zshrc

Add the following at the end of the file:

export NVM_DIR="$HOME/.nvm"
[ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh"

Save the file (Ctrl+O, Enter, then Ctrl+X), then reload it:

source ~/.zshrc

For Bash Users

Edit your .bashrc:

nano ~/.bashrc

Add the same lines at the end:

export NVM_DIR="$HOME/.nvm"
[ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh"

Save and reload:

source ~/.bashrc

Verify It’s Working

After applying the changes, open a new terminal and run:

nvm -v

You should now see the installed version, confirming that NVM loads correctly every time.

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Installing Node.js Versions

Check Installed Versions

First, see what versions you currently have installed:

nvm ls

Initially, you might only see:

->       system
iojs -> N/A (default)
node -> stable (-> N/A) (default)
unstable -> N/A (default)

Install Specific Versions

Install the Node.js versions you need for your projects. For example:

nvm install 14
nvm install 16
nvm install 18
nvm install 20

Switch Between Versions

To use a specific version:

nvm use 16

To set a default version:

nvm alias default 18

View All Installed Versions

Once you have multiple versions installed, check them with:

nvm ls

The arrow (->) indicates which version is currently active.

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Common NVM Commands

Command	Description
nvm install <version>	Install a specific Node.js version
nvm use <version>	Switch to a specific version
nvm ls	List all installed versions
nvm ls-remote	List all available versions to install
nvm alias default <version>	Set a default Node.js version
nvm current	Display the currently active version
nvm which <version>	Show the path to a specific version
nvm uninstall <version>	Remove a specific version

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Best Practices

• Install the LTS (Long Term Support) versions for production projects
• Use the latest version for experimenting with new features
• Set a sensible default version using nvm alias default <version>
• Switch to the project’s required Node version before running npm install
• Consider using a .nvmrc file in your project root to specify the required Node version