if ! command -v curl > /dev/null || ! command -v git > /dev/null || ! command -v expect > /dev/null || ! command -v rsync > /dev/null || ! command -v unbuffer; then
  if command -v apt-get > /dev/null; then
    ### Debian / Ubuntu
    logg info 'Running sudo apt-get update' && sudo apt-get update
    logg info 'Running sudo apt-get install -y build-essential curl expect git rsync procps file' && sudo apt-get install -y build-essential curl expect git rsync procps file
  elif command -v dnf > /dev/null; then
    ### Fedora
    logg info 'Running sudo dnf groupinstall -y "Development Tools"' && sudo dnf groupinstall -y 'Development Tools'
    logg info 'Running sudo dnf install -y curl expect git rsync procps-ng file' && sudo dnf install -y curl expect git rsync procps-ng file
  elif command -v yum > /dev/null; then
    ### CentOS
    logg info 'Running sudo yum groupinstall -y "Development Tools"' && sudo yum groupinstall -y 'Development Tools'
    logg info 'Running sudo yum install -y curl expect git rsync procps-ng file' && sudo yum install -y curl expect git rsync procps-ng file
  elif command -v pacman > /dev/null; then
    ### Archlinux
    logg info 'Running sudo pacman update' && sudo pacman update
    logg info 'Running sudo pacman -Syu base-devel curl expect git rsync procps-ng file' && sudo pacman -Syu base-devel curl expect git rsync procps-ng file
  elif command -v zypper > /dev/null; then
    ### OpenSUSE
    logg info 'Running sudo zypper install -yt pattern devel_basis' && sudo zypper install -yt pattern devel_basis
    logg info 'Running sudo zypper install -y curl expect git rsync procps file' && sudo zypper install -y curl expect git rsync procps file
  elif command -v apk > /dev/null; then
    ### Alpine
    logg info 'Running sudo apk add build-base curl expect git rsync ruby procps file' && sudo apk add build-base curl expect git rsync ruby procps file
  elif [ -d /Applications ] && [ -d /Library ]; then
    ### macOS
    logg info "Ensuring Xcode Command Line Tools are installed.."
    if ! xcode-select -p >/dev/null 2>&1; then
      logg info "Command Line Tools for Xcode not found"
      ### This temporary file prompts the 'softwareupdate' utility to list the Command Line Tools
      touch /tmp/.com.apple.dt.CommandLineTools.installondemand.in-progress;
      XCODE_PKG="$(softwareupdate -l | grep "\*.*Command Line" | tail -n 1 | sed 's/^[^C]* //')"
      logg info "Installing from softwareupdate" && softwareupdate -i "$XCODE_PKG" && logg success "Successfully installed $XCODE_PKG"
    fi
  elif [[ "$OSTYPE" == 'cygwin' ]] || [[ "$OSTYPE" == 'msys' ]] || [[ "$OSTYPE" == 'win32' ]]; then
    ### Windows
    logg info 'Running choco install -y curl expect git rsync' && choco install -y curl expect git rsync
  elif command -v nix-env > /dev/null; then
    ### NixOS
    logg warn "TODO - Add support for NixOS"
  elif [[ "$OSTYPE" == 'freebsd'* ]]; then
    ### FreeBSD
    logg warn "TODO - Add support for FreeBSD"
  elif command -v pkg > /dev/null; then
    ### Termux
    logg warn "TODO - Add support for Termux"
  elif command -v xbps-install > /dev/null; then
    ### Void
    logg warn "TODO - Add support for Void"
  fi
fi