Lazy loading command setup

This is a pattern one can use to post-pone expensive setup calls, shortening shell startup time:

if [ $commands[kubectl] ]; then
  kubectl() {
    unfunction "$0"
    source <(kubectl completion zsh)
    $0 "$@"
  }
fi

However, the zsh completion system seems sofisticated enough to handle this out of the box, as long as completion scripts are supplied in the correct way. Take a look in /usr/share/zsh/site-functions.

A similar pattern can be used to load tools like nvm on demand:

nvm() {

  unfunction "$0"

  [ -z "$NVM_DIR" ] && export NVM_DIR="$HOME/.nvm"
  source /usr/share/nvm/nvm.sh
  source /usr/share/nvm/install-nvm-exec

  $0 "$@"
}

Source