func init() {
  rootCmd.PersistentFlags().StringP(config.VariableXFlag, "x", config.VariableXDefault, "Variable X")
  rootCmd.PersistentFlags().StringP(config.VariableYFlag, "y", config.VariableYDefault, "Variable Y")

  rootCmd.AddCommand(&cobra.Command{
    Short: "Print injected variables",
    Use: "print",
    Run: func(cmd *cobra.Command, args []string) {
      fmt.Printf("VariableX: %s\n", viper.GetString(config.VariableXFlag))
      fmt.Printf("VariableY: %s\n", viper.GetString(config.VariableYFlag))
    },
  })

  rootCmd.AddCommand(&cobra.Command{
    Use: "version",
    Short: "Print version",
    Run: func(cmd *cobra.Command, args []string) {
      fmt.Println(version)
    },
  })

  viper.SetEnvKeyReplacer(strings.NewReplacer("-", "_"))
  viper.AutomaticEnv() // reads environment variables
  viper.BindPFlag(config.VariableXFlag, rootCmd.PersistentFlags().Lookup(config.VariableXFlag))
  viper.BindPFlag(config.VariableYFlag, rootCmd.PersistentFlags().Lookup(config.VariableYFlag))
}