Sbt-ugli er is a plugin for Sbt that uglifies Scala source code by surrounding it with package blocks, replacing newlines with whitespace or semicolons, and concatenating all sources. It was demonstrated to successfully uglify and test the scala-csv library but encountered errors when trying to uglify nscala-time, possibly due to a bug in Scala. The purpose of the plugin is to write jokes and report issues rather than for practical use.