Node.js | Holy Grail

What is Node.js?

Node.js is an asynchronous event-driven JavaScript runtime designed to build scalable network applications.

As an asynchronous event-driven JavaScript runtime, Node.js is designed to build scalable network applications, in contrast to today’s more common concurrency model, in which OS threads are employed. Thread-based networking is relatively inefficient and very difficult to use. Node.js is free from worries of dead-locking the process, since there are no locks.

Node.js is required for many development tools, including Appium testing for mobile automation testing.

Prerequisites

Homebrew foundation ZSH / Oh My ZSH! foundation

Install nvm (Node Version Manager)

nvm is a version manager for Node.js, designed to be installed per-user, and invoked per-shell. nvm works on any POSIX-compliant shell (sh, dash, ksh, zsh, bash) on unix, macOS, and Windows Subsystem for Linux.

Install nvm:

curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.40.4/install.sh | bash

Close your terminal session.

The installation script should automatically add nvm to your ~/.zshrc or ~/.bashrc config file. If not, add manually:

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

Verify Your Installation

Open a new terminal session:

nvm -v
# or
nvm --version

Install Node.js

Install the latest LTS version:

nvm install --lts

Install a specific version:

nvm install <version>

Install the latest version:

nvm install node

Install the latest npm release only:

nvm install-latest-npm

Managing Node.js Versions

List installed versions:

nvm ls

List available versions:

nvm ls-remote

Use a specific version:

nvm use <version>

Switch to the latest LTS version:

nvm use --lts

Set default version:

nvm alias default <version>

Create a custom alias:

nvm alias <alias_name> <version>

Delete an alias:

nvm unalias <alias_name>

Find the path to a Node executable:

nvm which <installed_node_version>

Check current Node version:

node -v
# or
node --version

Check current npm version:

npm -v
# or
npm --version

Uninstalling

Determine How Node.js Was Installed

which node

Output	Installed Via
`~/.nvm/versions/node/...`	nvm
`~/.local/share/fnm/...`	fnm
`/opt/homebrew/bin/node`	Homebrew (Apple Silicon)
`/usr/local/bin/node`	Homebrew (Intel) or direct install

Uninstall Node.js Versions (nvm)

If you get an error: nvm: Cannot uninstall currently-active node version when uninstalling any currently-active version, run nvm deactivate first.

# list installed versions
nvm ls

# uninstall a specific version
nvm uninstall <version>

# uninstall the latest LTS version
nvm uninstall --lts

Uninstall nvm

Remove nvm and all Node.js versions it manages:

rm -rf ~/.nvm

Remove the nvm initialization lines from your shell config file (~/.zshrc, ~/.bashrc, ~/.bash_profile, ~/.profile, or ~/.config/fish/config.fish):

# remove these lines
export NVM_DIR="$HOME/.nvm"
[ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh"
[ -s "$NVM_DIR/bash_completion" ] && \. "$NVM_DIR/bash_completion"

Restart your shell or source the edited file for changes to take effect.

Uninstall fnm

fnm stores versions in $FNM_DIR if set, otherwise $XDG_DATA_HOME/fnm (defaults to ~/.local/share/fnm). Older installs may use ~/.fnm.

# remove fnm and all managed versions (use your actual path)
rm -rf "${FNM_DIR:-${XDG_DATA_HOME:-$HOME/.local/share}/fnm}"
rm -rf ~/.fnm  # if it exists (older installs)

# if installed via Homebrew
brew uninstall fnm

Remove fnm initialization from your shell config file (~/.zshrc, ~/.bashrc, ~/.bash_profile, ~/.profile, or ~/.config/fish/config.fish):

# remove this line
eval "$(fnm env)"

Uninstall Homebrew-installed Node.js

brew uninstall node
brew cleanup --prune-prefix

If brew uninstall node fails due to dependency errors, use brew uninstall --ignore-dependencies node instead.

Uninstall Official Installer (.pkg)

If Node.js was installed from the official .pkg installer from nodejs.org:

sudo rm -rf /usr/local/bin/node
sudo rm -rf /usr/local/bin/npm
sudo rm -rf /usr/local/bin/npx
sudo rm -rf /usr/local/include/node
sudo rm -rf /usr/local/lib/node_modules
sudo rm -rf /usr/local/lib/dtrace/node.d
sudo rm -rf /usr/local/share/doc/node
sudo rm -rf /usr/local/share/man/man1/node*
sudo rm -rf /usr/local/share/man/man1/npm*
sudo rm -rf /usr/local/share/systemtap/tapset/node.stp

Remove npm and Global Packages

rm -rf ~/.npm
rm -rf ~/.node-gyp
rm -rf ~/.npmrc
rm -rf ~/.node_repl_history

Remove Yarn or pnpm (If Installed)

# yarn
rm -rf ~/.yarn
rm -rf ~/.yarnrc
rm -rf ~/.yarnrc.yml

# pnpm
rm -rf ~/.local/share/pnpm
rm -rf ~/.config/pnpm

Verify Removal

# all should return "command not found"
which node
which npm
which npx

# nvm is a shell function, not a binary
command -v nvm

Good to Know

Alternative: fnm (Fast Node Manager)

fnm is a faster alternative to nvm, written in Rust. It supports .nvmrc files and is compatible with nvm’s version syntax:

# Install via Homebrew
brew install fnm

# Add to ~/.zshrc
eval "$(fnm env)"

# Usage is similar to nvm
fnm install --lts
fnm use <version>

fnm has significantly faster shell startup times compared to nvm. Consider it if nvm is slowing down your terminal.

Troubleshooting

”nvm: command not found”

Verify nvm is installed:
```
ls ~/.nvm
```
Check your shell config has nvm initialization:
```
grep -A 3 'NVM_DIR' ~/.zshrc
```
Re-source your shell:
```
source ~/.zshrc
```

“node: command not found” After Installing

Set a default Node version:

nvm alias default <version>
# or
nvm alias default lts/*

Permission Errors with npm

Never use sudo with npm. Fix permissions:

# Create a directory for global packages
mkdir ~/.npm-global
npm config set prefix "$HOME/.npm-global"

# Add to PATH in ~/.zshrc
export PATH="$HOME/.npm-global/bin:$PATH"

nvm Slowing Down Shell Startup

nvm can slow down shell initialization. For faster startup, use lazy loading in ~/.zshrc:

# Lazy load nvm
nvm() {
  unset -f nvm node npm npx
  export NVM_DIR="$HOME/.nvm"
  [ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh"
  nvm "$@"
}

Different Node Version in Different Terminals

Use .nvmrc file in your project:

echo "18" > .nvmrc
nvm use

Add to shell config for automatic switching:

# Add to ~/.zshrc
autoload -U add-zsh-hook
load-nvmrc() {
  local nvmrc_path="$(nvm_find_nvmrc)"
  if [ -n "$nvmrc_path" ]; then
    local nvmrc_node_version=$(nvm version "$(cat "$nvmrc_path")")
    if [ "$nvmrc_node_version" = "N/A" ]; then
      nvm install
    elif [ "$nvmrc_node_version" != "$(nvm version)" ]; then
      nvm use --silent
    fi
  elif [ -n "$(PWD=$OLDPWD nvm_find_nvmrc)" ] \
    && [ "$(nvm version)" != "$(nvm version default)" ]; then
    nvm use default --silent
  fi
}
add-zsh-hook chpwd load-nvmrc
load-nvmrc

Resources

🔗

About Node.js nodejs.org

Official introduction to Node.js and its architecture

🔗

nvm on GitHub github.com

Node Version Manager - manage multiple Node.js versions