scalajs-bundler is a module bundler for Scala.js projects that use npm packages: it bundles the .js file emitted by the Scala.js compiler with its npm dependencies into a single .js file executable by Web browsers.

scalajs-bundler uses npm and webpack under the hood.

Last stable version is 0.18.0:

// For Scala.js 1.x
addSbtPlugin("ch.epfl.scala" % "sbt-scalajs-bundler" % "0.18.0")
// Or, for Scala.js 0.6.x
addSbtPlugin("ch.epfl.scala" % "sbt-scalajs-bundler-sjs06" % "0.18.0")

See the getting started page for more details about the setup process.