Ruby (programming language)
Matsumoto defined it this way in an interview:Ruby is object-oriented: every value is an object, including classes and instances of types that many other languages designate as primitives (such as integers, booleans, and "null"). Variables always hold references to objects. Every function is a method and methods are always called on an object. Methods defined at the top level scope become methods of the Object class. Since this class is an ancestor of every other class, such methods can be called on any object. They are also visible in all scopes, effectively serving as "global" procedures. Ruby supports inheritance with dynamic dispatch, mixins and singleton methods (belonging to, and defined for, a single instance rather than being defined on the class). Though Ruby does not support multiple inheritance, classes can import modules as mixins.
Apache Buildr
Though Buildr's general philosophy is similar to Maven, it uses Ruby's scripting possibilities to provide a more flexible and customizable programming model. The user writes a Ruby build script, declaring a project, its sub-projects, artifacts, dependencies, packaging rules, etc. Based on these declarations, a list of standard targets are provided to compile or package the project, upload a prepared package to a remote repository, clean up the build results, run tests and so on. Hooks are provided to execute custom Ruby code before or after the standard targets, allowing the user to comfortably override any defaults and further specify the behavior of the standard targets. New, completely user-written targets can be added.