Don't do this. Don't do any of it.

// in plugins.sbt
addSbtPlugin("com.codecommit" % "sbt-evil-mode" % "0.1-bdad513")

lazy val root = project
  .in(file("."))
  .gitHubDependency("djspiewak", "scala-collections", "c785a40")

The above creates a source dependency on hash c785a40 of the djspiewak/scala-collections project on github. Don't do this. Oh, tags probably also work. Haven't tried it. You shouldn't either.

Now, if you're truly an evil person (let's face it, why else would you be reading this?), then what you probably really want is a way to depend on HEAD of a given project. Mercifully, SBT prevents this due to entirely unrelated architectural constraints. So you can't!

...yet