ATL is one of the most widely used model-to-model transformation languages. Often, software designers and developers using MDE techniques have difficulties executing ATL transformations outside the Eclipse platform. An advantage of implementing these transformations in a standalone way is that they can be used for handling models at runtime. This paper presents a web tool which uses ATL and EMF libraries to provide model transformation and model validation services. These functionalities are used to implement an adaptation process built up from a set of M2M transformations aimed to dynamically generate a new M2M transformation (which does not exist a priori) from a rule repository model. This new transformation is responsible for adapting component-based software systems. The web tool also offers a GUI to test and verify the adaptation process.