SGI’s RapidApp was originally based on Builder Xcessory Version 3 source code. Consequently, RapidApp and Builder Xcessory share many of the same approaches to GUI development. And when SGI took RapidApp to End of Life, Builder Xcessory was given the nod as the official SGI recommended upgrade path for RapidApp users.

The actual process of converting involves the running of a converter on the RapidApp save file. This converter only supports RapidApp save files that were created using RapidApp 1.2+. The converter is written in Python, allowing users to extend and modify it as necessary to address any unique needs of their RapidApp user interface.