Eldev (Elisp development tool) is an Emacs-based build tool, targeted solely at Elisp projects. It is an alternative to Cask. Unlike Cask, Eldev itself is fully written in Elisp and its configuration files are also Elisp programs. If you are familiar with Java world, Cask can be seen as a parallel to Maven — it uses project description, while Eldev is sort of a parallel to Gradle — its configuration is a program on its own.