In this paper, we lay out the design time and space of component assembly in a visual builder, and propose concrete ways of also handling context components seamlessly. We present an environment that allows Java developers to test and evaluate JavaBeans components implementing the extensible runtime containment and services protocol. We enhanced the BeanBox from the Bean Development Kit (BDK) with new visual manipulation capabilities for nested beans, so that it is possible to drag and drop, serialize and de-serialize, group and ungroup, nested beans. By means of these visual manipulations, child beans can be visually put inside context beans.