$ ./mac_prereq.sh 
Ensuring homebrew caskroom is installed...
==> Tapping caskroom/cask
Cloning into '/usr/local/Homebrew/Library/Taps/caskroom/homebrew-cask'...
remote: Enumerating objects: 4106, done.
remote: Counting objects: 100% (4106/4106), done.
remote: Compressing objects: 100% (4096/4096), done.
remote: Total 4106 (delta 22), reused 421 (delta 8), pack-reused 0
Receiving objects: 100% (4106/4106), 1.32 MiB | 1.40 MiB/s, done.
Resolving deltas: 100% (22/22), done.
Tapped 1 command and 3999 casks (4,112 files, 4.2MB).
Installing docker for mac and minikube...
==> Tapping homebrew/cask
Cloning into '/usr/local/Homebrew/Library/Taps/homebrew/homebrew-cask'...
remote: Enumerating objects: 4106, done.
remote: Counting objects: 100% (4106/4106), done.
remote: Compressing objects: 100% (4096/4096), done.
remote: Total 4106 (delta 22), reused 421 (delta 8), pack-reused 0
Receiving objects: 100% (4106/4106), 1.32 MiB | 1.20 MiB/s, done.
Resolving deltas: 100% (22/22), done.
Tapped 1 command and 3999 casks (4,112 files, 4.2MB).
==> Satisfying dependencies
==> Downloading https://download.docker.com/mac/stable/31259/Docker.dmg
######################################################################## 100.0%
==> Verifying SHA-256 checksum for Cask 'docker'.
==> Installing Cask docker
==> Moving App 'Docker.app' to '/Applications/Docker.app'.
🍺  docker was successfully installed!
==> Satisfying dependencies
==> Installing Formula dependencies: kubernetes-cli
==> Installing kubernetes-cli
==> Downloading https://homebrew.bintray.com/bottles/kubernetes-cli-1.14.0.high_sierra.bottle.tar.gz
######################################################################## 100.0%
==> Pouring kubernetes-cli-1.14.0.high_sierra.bottle.tar.gz
==> Caveats
Bash completion has been installed to:
  /usr/local/etc/bash_completion.d

zsh completions have been installed to:
  /usr/local/share/zsh/site-functions
==> Summary
🍺  /usr/local/Cellar/kubernetes-cli/1.14.0: 220 files, 47.9MB
==> Downloading https://storage.googleapis.com/minikube/releases/v1.0.0/minikube-darwin-amd64
######################################################################## 100.0%
==> Verifying SHA-256 checksum for Cask 'minikube'.
==> Installing Cask minikube
==> Linking Binary 'minikube-darwin-amd64' to '/usr/local/bin/minikube'.
🍺  minikube was successfully installed!
Installing hyperkit and helm...
==> Installing dependencies for docker-machine-driver-hyperkit: docker-machine
==> Installing docker-machine-driver-hyperkit dependency: docker-machine
==> Downloading https://homebrew.bintray.com/bottles/docker-machine-0.16.1.high_sierra.bottle.tar.gz
######################################################################## 100.0%
==> Pouring docker-machine-0.16.1.high_sierra.bottle.tar.gz
==> Caveats
Bash completion has been installed to:
  /usr/local/etc/bash_completion.d

zsh completions have been installed to:
  /usr/local/share/zsh/site-functions

To have launchd start docker-machine now and restart at login:
  brew services start docker-machine
Or, if you don't want/need a background service you can just run:
  docker-machine start
==> Summary
🍺  /usr/local/Cellar/docker-machine/0.16.1: 11 files, 35.8MB
==> Installing docker-machine-driver-hyperkit
==> Downloading https://homebrew.bintray.com/bottles/docker-machine-driver-hyperkit-1.0.0.high_sierra.bottle.tar.gz
######################################################################## 100.0%
==> Pouring docker-machine-driver-hyperkit-1.0.0.high_sierra.bottle.tar.gz
==> Caveats
This driver requires superuser privileges to access the hypervisor. To
enable, execute:
  sudo chown root:wheel /usr/local/opt/docker-machine-driver-hyperkit/bin/docker-machine-driver-hyperkit
  sudo chmod u+s /usr/local/opt/docker-machine-driver-hyperkit/bin/docker-machine-driver-hyperkit
==> Summary
🍺  /usr/local/Cellar/docker-machine-driver-hyperkit/1.0.0: 5 files, 13.5MB
==> Installing dependencies for hyperkit: libev
==> Installing hyperkit dependency: libev
==> Downloading https://homebrew.bintray.com/bottles/libev-4.24.high_sierra.bottle.tar.gz
######################################################################## 100.0%
==> Pouring libev-4.24.high_sierra.bottle.tar.gz
🍺  /usr/local/Cellar/libev/4.24: 12 files, 432.8KB
==> Installing hyperkit
==> Downloading https://homebrew.bintray.com/bottles/hyperkit-0.20180403.high_sierra.bottle.tar.gz
######################################################################## 100.0%
==> Pouring hyperkit-0.20180403.high_sierra.bottle.tar.gz
🍺  /usr/local/Cellar/hyperkit/0.20180403: 5 files, 4MB
==> Downloading https://homebrew.bintray.com/bottles/kubernetes-helm-2.13.1.high_sierra.bottle.tar.gz
######################################################################## 100.0%
==> Pouring kubernetes-helm-2.13.1.high_sierra.bottle.tar.gz
==> Caveats
Bash completion has been installed to:
  /usr/local/etc/bash_completion.d

zsh completions have been installed to:
  /usr/local/share/zsh/site-functions
==> Summary
🍺  /usr/local/Cellar/kubernetes-helm/2.13.1: 51 files, 84.2MB
==> Caveats
==> docker-machine
Bash completion has been installed to:
  /usr/local/etc/bash_completion.d

zsh completions have been installed to:
  /usr/local/share/zsh/site-functions

To have launchd start docker-machine now and restart at login:
  brew services start docker-machine
Or, if you don't want/need a background service you can just run:
  docker-machine start
==> docker-machine-driver-hyperkit
This driver requires superuser privileges to access the hypervisor. To
enable, execute:
  sudo chown root:wheel /usr/local/opt/docker-machine-driver-hyperkit/bin/docker-machine-driver-hyperkit
  sudo chmod u+s /usr/local/opt/docker-machine-driver-hyperkit/bin/docker-machine-driver-hyperkit
==> kubernetes-helm
Bash completion has been installed to:
  /usr/local/etc/bash_completion.d

zsh completions have been installed to:
  /usr/local/share/zsh/site-functions
Giving hyperkit driver superuser privileges...
Password:
Making /usr/local/opt/docker-machine-driver-hyperkit/bin/docker-machine-driver-hyperkit setuid...Making launchd start docker now and on log-in...
==> Tapping homebrew/services
Cloning into '/usr/local/Homebrew/Library/Taps/homebrew/homebrew-services'...
remote: Enumerating objects: 17, done.
remote: Counting objects: 100% (17/17), done.
remote: Compressing objects: 100% (14/14), done.
remote: Total 17 (delta 0), reused 12 (delta 0), pack-reused 0
Unpacking objects: 100% (17/17), done.
Tapped 1 command (50 files, 62.7KB).
==> Successfully started `docker-machine` (label: homebrew.mxcl.docker-machine)
Making hyperkit the default VM driver...
⚠️  These changes will take effect upon a minikube delete and then a minikube start