The new M-PAGES software by NGS is written in C++, with a bit of python tooling as well. This is to replace the original PAGES software, which was written in F

The new M-PAGES software by NGS is written in C++, with a bit of python tooling as well. This is to replace the original PAGES software, which was written in Fortran. M-PAGES is able to process GNSS baselines using all the new satellite systems, as opposed to only GPS. Edit - my understanding is they chose that language for good extensibility.