1. Command Line Reference

Command Line Reference 

This page is a relatively complete list of command line options, commands, and tasks you can use from the sbt interactive prompt or in batch mode. See Running in the Getting Started Guide for an intro to the basics, while this page has a lot more detail.

Notes on the command line 

  • There is a technical distinction in sbt between tasks, which are “inside” the build definition, and commands, which manipulate the build definition itself. If you’re interested in creating a command, see Commands. This specific sbt meaning of “command” means there’s no good general term for “thing you can type at the sbt prompt”, which may be a setting, task, or command.
  • Some tasks produce useful values. The toString representation of these values can be shown using show <task> to run the task instead of just <task>.
  • In a multi-project build, execution dependencies and the aggregate setting control which tasks from which projects are executed. See multi-project builds.

Project-level tasks 

  • clean Deletes all generated files (the target directory).
  • publishLocal Publishes artifacts (such as jars) to the local Ivy repository as described in Publishing.
  • publish Publishes artifacts (such as jars) to the repository defined by the publishTo setting, described in Publishing.
  • update Resolves and retrieves external dependencies as described in library dependencies.

Configuration-level tasks 

Configuration-level tasks are tasks associated with a configuration. For example, compile, which is equivalent to Compile/compile, compiles the main source code (the compile configuration). Test/compile compiles the test source code (test test configuration). Most tasks for the compile configuration have an equivalent in the test configuration that can be run using a Test/ prefix.

  • compile Compiles the main sources (in the src/main/scala directory). Test/compile compiles test sources (in the src/test/scala/ directory).
  • console Starts the Scala interpreter with a classpath including the compiled sources, all jars in the lib directory, and managed libraries. To return to sbt, type :quit, Ctrl+D (Unix), or Ctrl+Z (Windows). Similarly, Test/console starts the interpreter with the test classes and classpath.
  • consoleQuick Starts the Scala interpreter with the project’s compile-time dependencies on the classpath. Test/consoleQuick uses the test dependencies. This task differs from console in that it does not force compilation of the current project’s sources.
  • consoleProject Enters an interactive session with sbt and the build definition on the classpath. The build definition and related values are bound to variables and common packages and values are imported. See the consoleProject documentation for more information.
  • doc Generates API documentation for Scala source files in src/main/scala using scaladoc. Test/doc generates API documentation for source files in src/test/scala.
  • package Creates a jar file containing the files in src/main/resources and the classes compiled from src/main/scala. Test/package creates a jar containing the files in src/test/resources and the class compiled from src/test/scala.
  • packageDoc Creates a jar file containing API documentation generated from Scala source files in src/main/scala. Test/packageDoc creates a jar containing API documentation for test sources files in src/test/scala.
  • packageSrc: Creates a jar file containing all main source files and resources. The packaged paths are relative to src/main/scala and src/main/resources. Similarly, Test/packageSrc operates on test source files and resources.
  • run <argument>* Runs the main class for the project in the same virtual machine as sbt. The main class is passed the arguments provided. Please see Running Project Code for details on the use of System.exit and multithreading (including GUIs) in code run by this action. Test/run runs a main class in the test code.
  • runMain <main-class> <argument>* Runs the specified main class for the project in the same virtual machine as sbt. The main class is passed the arguments provided. Please see Running Project Code for details on the use of System.exit and multithreading (including GUIs) in code run by this action. Test/runMain runs the specified main class in the test code.
  • test Runs all tests detected during test compilation. See Testing for details.
  • testOnly <test>* Runs the tests provided as arguments. * (will be) interpreted as a wildcard in the test name. See Testing for details.
  • testQuick <test>* Runs the tests specified as arguments (or all tests if no arguments are given) that:

    1. have not been run yet OR
    2. failed the last time they were run OR
    3. had any transitive dependencies recompiled since the last successful run * (will be) interpreted as a wildcard in the test name. See [Testing][Testing] for details.

General commands 

  • exit or quit End the current interactive session or build. Additionally, Ctrl+D (Unix) or Ctrl+Z (Windows) will exit the interactive prompt.
  • help <command> Displays detailed help for the specified command. If the command does not exist, help lists detailed help for commands whose name or description match the argument, which is interpreted as a regular expression. If no command is provided, displays brief descriptions of the main commands. Related commands are tasks and settings.
  • projects [add|remove <URI>] List all available projects if no arguments provided or adds/removes the build at the provided URI. (See multi-project builds for details on multi-project builds.)
  • project <project-id> Change the current project to the project with ID <project-id>. Further operations will be done in the context of the given project. (See multi-project builds for details on multiple project builds.)
  • ~ <command> Executes the project specified action or method whenever source files change. See Triggered Execution for details.
  • < filename Executes the commands in the given file. Each command should be on its own line. Empty lines and lines beginning with ’#’ are ignored
  • + <command> Executes the project specified action or method for all versions of Scala defined in the crossScalaVersions setting.
  • ++ <version|home-directory> <command> Temporarily changes the version of Scala building the project and executes the provided command. <command> is optional. The specified version of Scala is used until the project is reloaded, settings are modified (such as by the set or session commands), or ++ is run again. <version> does not need to be listed in the build definition, but it must be available in a repository. Alternatively, specify the path to a Scala installation.
  • ; A ; B Execute A and if it succeeds, run B. Note that the leading semicolon is required.
  • eval <Scala-expression> Evaluates the given Scala expression and returns the result and inferred type. This can be used to set system properties, as a calculator, to fork processes, etc … For example:

    > eval System.setProperty("demo", "true")
    > eval 1+1
    > eval "ls -l" !

Commands for managing the build definition 

  • reload [plugins|return] If no argument is specified, reloads the build, recompiling any build or plugin definitions as necessary. reload plugins changes the current project to the build definition project (in project/). This can be useful to directly manipulate the build definition. For example, running clean on the build definition project will force snapshots to be updated and the build definition to be recompiled. reload return changes back to the main project.
  • set <setting-expression> Evaluates and applies the given setting definition. The setting applies until sbt is restarted, the build is reloaded, or the setting is overridden by another set command or removed by the session command. See .sbt build definition and Inspecting Settings for details.
  • session <command> Manages session settings defined by the set command. It can persist settings configured at the prompt. See Inspecting Settings for details.
  • inspect <setting-key> Displays information about settings, such as the value, description, defining scope, dependencies, delegation chain, and related settings. See Inspecting Settings for details.

Sbt runner arguments 

When launching the sbt runner from the OS shell, various system properties or JVM extra options can be specified to influence its behaviour.

sbt JVM options and system properties 

If the JAVA_OPTS and/or SBT_OPTS environment variables are defined when sbt starts, their content is passed as command line arguments to the JVM running sbt.

If a file named .jvmopts exists in the current directory, its content is appended to JAVA_OPTS at sbt startup. Similarly, if .sbtopts and/or /etc/sbt/sbtopts exist, their content is appended to SBT_OPTS. The default value of JAVA_OPTS is -Dfile.encoding=UTF8.

You can also specify JVM system properties and command line options directly as sbt arguments: any -Dkey=val argument will be passed as-is to the JVM, and any -J-Xfoo will be passed as -Xfoo.

See also sbt --help for more details.

sbt JVM heap, permgen, and stack sizes 

If you find yourself running out of permgen space or your workstation is low on memory, adjust the JVM configuration as you would for any java application.

For example a common set of memory-related options is:

export SBT_OPTS="-Xmx2048M -Xss2M"

Or if you prefer to specify them just for this session:

sbt -J-Xmx2048M -J-Xss2M

Boot directory 

sbt is just a bootstrap, the actual meat of sbt, the Scala compiler and standard library are by default downloaded to the shared directory $HOME/.sbt/boot/.

To change the location of this directory, set the sbt.boot.directory system property. A relative path will be resolved against the current working directory, which can be useful if you want to avoid sharing the boot directory between projects. For example, the following uses the pre-0.11 style of putting the boot directory in project/boot/:

sbt -Dsbt.boot.directory=project/boot/

Terminal encoding 

The character encoding used by your terminal may differ from Java’s default encoding for your platform. In this case, you will need to specify the file.encoding=<encoding> system property, which might look like:

export JAVA_OPTS="-Dfile.encoding=Cp1252"


On Unix, sbt will pick up any HTTP, HTTPS, or FTP proxy settings from the standard http_proxy, https_proxy, and ftp_proxy environment variables. If you are behind a proxy requiring authentication, you need to pass some supplementary flags at sbt startup. See JVM networking system properties for more details.

For example:

sbt -Dhttp.proxyUser=username -Dhttp.proxyPassword=mypassword

On Windows, your script should set properties for proxy host, port, and if applicable, username and password. For example, for HTTP:

sbt -Dhttp.proxyHost=myproxy -Dhttp.proxyPort=8080 -Dhttp.proxyUser=username -Dhttp.proxyPassword=mypassword

Replace http with https or ftp in the above command line to configure HTTPS or FTP.

Other system properties 

The following system properties can also be passed to sbt:

Property Values Default Meaning
sbt.banner Boolean true (in 1.3+) Show a welcome banner advertising new features.
sbt.boot.directory Directory ~/.sbt/boot Path to shared boot directory. You should define sbt.boot.directory explicitly if you are using sbt in a CI environment and want to cache sbt boot classes between runs.
sbt.boot.properties File Roughly sbt.boot.properties internal to the sbt launcher and specific to the sbt version. The path to find the sbt boot properties file. This can be a relative path, relative to the sbt base directory, the users home directory or the location of the sbt jar file, or it can be an absolute path or an absolute file URI.
sbt.ci Boolean false (unless then env var BUILD_NUMBER is set) For continuous integration environments. Suppress supershell and color.
sbt.client Boolean false
sbt.color String auto Supersedes sbt.log.format. To turn on color, use always or true. To turn off color, use never or false>. To use color if the output is a terminal (not a pipe) that supports color, use auto.
sbt.coursier Boolean true (in 1.3+) Use coursier to retrieve packages. (See also sbt.ivy.)
sbt.coursier.home Directory CoursierDependencyResolution.defaultCacheLocation (in 1.3+) Location of coursier artifact cache, where the default is defined by Coursier cache resolution logic. You can verify the value with the command `csrCacheDirectory`. You should define sbt.coursier.home explicitly if you are using coursier in a CI environment and want to cache artifacts between runs.
sbt.extraClasspath Classpath Entries (jar files or directories) that are added to sbt's classpath. Note that the entries are delimited by comma, e.g.: entry1, entry2,... See also resource in the sbt launcher documentation.
sbt.genbuildprops Boolean true Generate build.properties if missing. If unset, this defers to sbt.skip.version.write.
sbt.global.base Directory $HOME/.sbt/1.0 The directory containing global settings and plugins.
xsbt.inc.debug Boolean false Extra debugging for the incremental debugger.
sbt.ivy Boolean true (in <1.3) Use ivy to retrieve packages.
sbt.ivy.home Directory ~/.ivy2 The directory containing the local Ivy repository and artifact cache. You should define sbt.ivy.home explicitly if you are using sbt in a CI environment and want to cache ivy artifacts between runs.
sbt.log.noformat Boolean false If true, disable ANSI color codes. Useful on build servers or terminals that do not support color.
sbt.main.class String sbt.xMain The sbt class to use (alternatives include sbt.ConsoleMain and sbt.ScriptMain).
sbt.offline Boolean false Avoid retrieving classes from repositories.
sbt.override.build.repos Boolean false If true, repositories configured in a build definition are ignored and the repositories configured for the launcher are used instead. See sbt.repository.config and the sbt launcher documentation.
sbt.progress String ? Use always to show progress ("supershell").
sbt.repository.config File ~/.sbt/repositories A file containing the repositories to use for the launcher. The format is the same as a [repositories] section for a sbt launcher configuration file. This setting is typically used in conjunction with setting sbt.override.build.repos to true (see sbt.override.build.repos and the sbt launcher documentation).
sbt.resident.limit Number 0 The number of scala compilers to keep around. This experimental feature was intended to improve compilation time. It does not appear to have succeeded and this flag will probably be removed.
sbt.skip.version.write Boolean false Generate build.properties if missing. See sbt.genbuildprops.
sbt.supershell Boolean true if color is enabled Use supershell (show progress at bottom of shell).
sbt.supershell.sleep Number 100 Time to wait between updating the supershell progress area.
sbt.task.timings Boolean false Measure the time elapsed for running tasks.
sbt.task.timings.omit.paths Boolean false Omit paths when reporting timings.
sbt.task.timings.on.shutdown Boolean false Report timings at JVM shutdown (instead of at task completion).
sbt.task.timings.threshold String 0 Omit items from timing report if they are below this threshold.
sbt.traces Boolean false Generate Chrome Trace Event Format log for tasks.
sbt.turbo Boolean false Use additional layered class loaders.
sbt.version Version 1.9.8 sbt version to use, usually taken from project/build.properties.
sbt.watch.mode String auto If polling, check file system periodically for updates.