Hello, I am working with Roassal and trying to write a cell-layout builder that uses RTPieBuilders internally as its nested objects. The nesting docs cover nesting RT elements, but not builders. The composition docs cover composing builders, but not nesting them. I have a partial solution, but it is getting increasingly hacky, to the point where it may be easier to just duplicate the piebuilder code in my builder. Before I go down that road, I wanted to check if there was a more natural way to nest builders. Below is a mashup of the Roassal Examples Nesting and Pie Chart builders that gives the basic flavor of what I am trying to accomplish. Notice that I am creating new PieBuilders every time, running them, and extracting their createdElements for my layout. This works well enough, but if I then want to normalize global properties so that all pie slices with the same property get the same color, I have no way to coordinate the newly generated PieBuilders, as each possesses its own normalizer. Likewise, if I have a global PieBuilder, its internal state gets trampled with each iteration. I figured there was likely an easy way to compose builders that I didn't know about, so I thought I would ask. | v es b | v := RTView new. es := RTEllipse elementsOn: RTShape withAllSubclasses. v addAll: es. RTNest new for: es add: [ :group :model | b := RTPieBuilder new. b objects: RTShape withAllSubclasses. b slice: #numberOfMethods. b normalizer distinctColor. b view: v. b build. group addAll: b createdElements. ]. RTCellLayout new lineItemsCount: 8; on: es. v Thanks, Evan