Enforcing framework adaptability is one of the key points in the process of building an object-oriented application framework. When it comes to simulation, some adaptation mechanisms to configure components on-the-fly are usually required in order to produce good software artifacts and alleviate development effort. The paper reports an experience using a simulation multi-agent framework, initially conceived to be used in fluid flow problems. The framework architecture demonstrated during its evolution a great potential regarding to flexibility and modularity, tackling a wide range of other problems ranging from a network protocol simulation to a soccer simulation.The contribution of the work is that it provides an adaptable framework architecture with a particular combination of building mechanisms such as agents, uniform decomposition, competing tasks, events and implicit invocation, to represent complex simulations in a flexible manner. In addition, it describes three application examples using the framework, showing both practical experience about framework evolution and derived research ideas in the targeted area.The work is organized into five sections. The first section gives background information about adaptability in object oriented systems and multi-agent systems. Then, the description of our framework Bubble is presented. The following section reports three application examples based on the framework and lessons learned in this evolution process. Then, some tradeoffs and perspectives about Bubble are discussed after that. And finally, we draw the conclusions of the work. BACKGROUND INFORMATIONThis section explains what we mean by adaptability in object oriented systems (closely related with the architecture of our framework), and presents basic concepts about multiagent systems and agent-based simulations, in order to situate the rest of the work.