The part of Root I use is Cling the C++ interpreter along with Xeus in a Jupyter notebook. I decided one night to test the fastest n-body from benchmarkgames comparing Xeus and Python 3. With Xeus I get 15.58 seconds and running the fastest Python code with Python3 kernel, both on binder using the same instance, I get 5 minutes. Output is exactly the same for both runs. Even with an overhead tax for running dynamic C++ at ~300% for this program Cling is very quick. SIMD and vectorization were not used just purely the code from benchmarkgames. I use Cling primarily as a quick stand-in JIT for languages that compile to C++.