What is nvm? 🤔

"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), in particular on these platforms: unix, macOS, and windows WSL".

How do I install nvm? 🤔

Simple, just head on over to their GitHub repository and follow the install instructions.

Why should I use nvm? 🤔

If you're developing software using the NodeJS runtime environment you're probably aware that you might want have multiple projects using different node versions, say one using 10 and another 12. This could be due to a number of reasons. It gets annoying switching between node versions manually.

Manual usage of nvm 🐌

The project nvm solves this problem by allowing the user to install node versions on the fly by using a simple command:

nvm install <NODE_VERSION_NUMBER>

You can also easily switch between node versions using a simple command:

nvm use <NODE_VERSION_NUMBER>

Automated usage of nvm 🤖

Let's face it, you're going to forget to switch to the correct node version at some point.

We can in a sense, automate the switching between versions.

It's a simple solution which only requires a one-time setup consisting of two steps:

1. Create a .nvmrc file in the root of your project folder with the version number you want to use.

12

2. Add the below snippet to your .zshrc file

autoload -U add-zsh-hook
load-nvmrc() {
  local node_version="$(nvm version)"
  local nvmrc_path="$(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" != "$node_version" ]; then
      nvm use
    fi
  elif [ "$node_version" != "$(nvm version default)" ]; then
    echo "Reverting to nvm default version"
    nvm use default
  fi
}
add-zsh-hook chpwd load-nvmrc
load-nvmrc

Now when you change directory it will look for a .nvmrc file automatically and switch to the correct version.

Found '/Users/thomaschaplin/projects/dummy_project/.nvmrc' with version <12>
Now using node v12.18.2 (npm v6.14.5)