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Version: 2.0.x

Introduction to ZIO CLI

Rapidly build powerful command-line applications powered by ZIO

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To use ZIO CLI, we need to add the following to our build.sbt file:

libraryDependencies += "dev.zio" %% "zio-cli" % "0.5.0"


import zio.Console.printLine
import zio.cli.HelpDoc.Span.text
import zio.cli._

import java.nio.file.{Path => JPath}

object GitExample extends ZIOCliDefault {
import java.nio.file.Path

sealed trait Subcommand extends Product with Serializable
object Subcommand {
final case class Add(modified: Boolean, directory: JPath) extends Subcommand
final case class Remote(verbose: Boolean) extends Subcommand
object Remote {
sealed trait RemoteSubcommand extends Subcommand
final case class Add(name: String, url: String) extends RemoteSubcommand
final case class Remove(name: String) extends RemoteSubcommand

val modifiedFlag: Options[Boolean] = Options.boolean("m")

val addHelp: HelpDoc = HelpDoc.p("Add subcommand description")
val add =
Command("add", modifiedFlag,"directory")).withHelp(addHelp).map { case (modified, directory) =>
Subcommand.Add(modified, directory)

val verboseFlag: Options[Boolean] = Options.boolean("verbose").alias("v")
val configPath: Options[Path] ="c", Exists.Yes)

val remoteAdd = {
val remoteAddHelp: HelpDoc = HelpDoc.p("Add remote subcommand description")
Command("add", Options.text("name") ++ Options.text("url")).withHelp(remoteAddHelp).map { case (name, url) =>
Subcommand.Remote.Add(name, url)

val remoteRemove = {
val remoteRemoveHelp: HelpDoc = HelpDoc.p("Remove remote subcommand description")
Command("remove", Args.text("name")).withHelp(remoteRemoveHelp).map(Subcommand.Remote.Remove)

val remoteHelp: HelpDoc = HelpDoc.p("Remote subcommand description")
val remote = {
Command("remote", verboseFlag)
.subcommands(remoteAdd, remoteRemove)

val git: Command[Subcommand] =
Command("git", Options.none, Args.none).subcommands(add, remote)

val cliApp = CliApp.make(
name = "Git Version Control",
version = "0.9.2",
summary = text("a client for the git dvcs protocol"),
command = git
) {
case Subcommand.Add(modified, directory) =>
printLine(s"Executing `git add $directory` with modified flag set to $modified")
case Subcommand.Remote.Add(name, url) =>
printLine(s"Executing `git remote add $name $url`")
case Subcommand.Remote.Remove(name) =>
printLine(s"Executing `git remote remove $name`")
case Subcommand.Remote(verbose) =>
printLine(s"Executing `git remote` with verbose flag set to $verbose")


object Example2 extends scala.App {



- add [-m] <directory> Add subcommand description
- remote [(-v, --verbose)] Remote subcommand description