At CERN, 50 million lines of C++ code are being used by about 10 thousand physicist. Many of them are not programming experts. To make writing C++ more accessible, ROOT, one of the core tools at CERN, has been using the CINT C++ interpreter for more than 15 years. CINT also opens up a whole new world of dynamic programming: plug-ins, signal/slot, runtime evaluation, reflection. In particular, the latter is fundamental to CERN and its petabytes of Large Hadron Collider data per year, which are created, serialized, and analyzed as C++ objects.