malliina / sbt-utils   1.6.36

MIT License GitHub

SBT plugin collection

Scala versions: 3.x 2.12
sbt plugins: 1.0

Build Status


A repository of sbt plugins that I find useful.

  • sbt-bundler for integrating servers using sbt-revolver with clients built with Scala.js and scalajs-bundler
  • sbt-utils-maven for publishing GitHub projects to Maven Central
  • sbt-nodejs for working with Scala and Node.js projects
  • sbt-filetree creates a data structure of your files

The Maven Central plugin populates the required POM XML and delegates publishing to sbt-sonatype. The user must provide a couple of values to correctly populate the POM XML, see Usage.


To use sbt-revolver-rollup:

addSbtPlugin("com.malliina" % "sbt-revolver-rollup" % "1.6.36")

To use sbt-bundler:

addSbtPlugin("com.malliina" % "sbt-bundler" % "1.6.36")

To publish to Maven Central:

addSbtPlugin("com.malliina" % "sbt-utils-maven" % "1.6.36")

The Node.js plugin:

addSbtPlugin("com.malliina" % "sbt-nodejs" % "1.6.36")

To use sbt-filetree:

addSbtPlugin("com.malliina" % "sbt-filetree" % "1.6.36")



Static site generation with hot reload support via sbt-revolver. Configure the frontend (Scala.js) and site generator.


Enable the frontend plugin:

val frontend = project

Create and edit package.json in


The following rollup inputs are available:





Enable the generator plugin and connect the frontend module:

val generator = project
    scalajsProject := frontend,
    hashPackage := "com.malliina.assets",

Assets generated by the frontend will be available in com.malliina.assets.HashedAssets.

Implement your site generation function and call it from the main method of the project. Write the site to directory BuildInfo.siteDir. I recommend Scalatags for HTML generation.

Run sbt ~build and navigate to http://localhost:10101 to view the site.


Define your project:

// Scala.js project
val client = project

// Backend restarted with sbt-revolver
val server = project
    clientProject := client

To run:

sbt ~start

The start command will fingerprint assets generated by scalajs-bundler (via webpack) and make them available as resources to the server module. Any changes to either the client or server will rebuild and reload. See example/build.sbt for a minimal example.

Maven Central

To publish to Maven Central, enable the MavenCentralPlugin SBT autoplugin for your project:

val myLibrary = Project("my-library", file("."))

Define the following SBT settings in order to populate the Maven POM XML correctly:

gitUserName := "My GitHub Username Here",
developerName := "My Name Here"

To publish the artifacts, run:

sbt release

You need credentials to publish.

The generated POM XML declares a license of


Plugin NodeJsPlugin lets you run npm commands from the sbt shell.

val myApp ="."))

Then run e.g.

front ncu

Set sbt setting cwd to your frontend working directory. (Typically, the directory containing package.json.) By default, it is baseDirectory.


This SBT plugin generates a Scala source file that represents the directory structure of a given file system directory.

For example, given a directory with the following structure:


The plugin generates (roughly) the following Scala object:

object AppAssets {
  def file1_jpg: String = "file1.jpg"
  def file2_jpg: String = "file2.jpg"
  object sub {
    def file3_jpg: String = "sub/file3.jpg"

Now you can refer to a given file path without writing the string literal by hand:

AppAssets.sub.file3_jpg // returns "sub/file3.jpg"

Furthermore, if the file is deleted or moved from the file system, any code that references the file will no longer compile.


Add the following settings in plugins.sbt:

addSbtPlugin("com.malliina" % "sbt-filetree" % "1.6.36")

Enable FileTreePlugin in your project:

val myProject = Project("demo", file("."))

Specify the source directories for the file tree traversal and corresponding destination objects to write:

import com.malliina.sbt.filetree.DirMap
fileTreeSources += DirMap(baseDirectory.value / "appfiles", "com.malliina.filetree.AppFiles")

Now when you compile, the build generates source code that defines an object com.malliina.filetree.AppFiles, where each member is a file or directory under baseDirectory / appfiles.

By default, each file path is represented as a String. You can supply a function as a third paramater to a DirMap that transforms each file path:

DirMap(baseDirectory.value / "appfiles", "com.malliina.filetree.AppFiles", "com.malliina.Code.transform")

Where transform is a unary function of type String => T.