From the recent advent of scripting tools integrated into commercial CAAD software and everyday design practice, the use of programming applied to an architectural design process becomes a necessary field of study. The presented research explores the use of programming as explorative and reflexive medium (Schin, 1983) through the development of a programming framework for architectural design. Based on Java, the ANAR+ library is a parametric geometry environment meant to be used as programming interface by designers. Form exploration strategies based on parametric variations depend on the internal logic description, a key role for form generation. In most commercial CAD software, geometric data structures are often predefined objects, thus constraining the form exploration, whereas digital architectural research and teaching are in need for an encompassing tool able to step beyond new software products limitations.