ROOT is a data analysis framework broadly used in and outside of High Energy
Physics (HEP). Since HEP software frameworks always strive for performance
improvements, ROOT was extended with experimental support of runtime C++
Modules. C++ Modules are designed to improve the performance of C++ code
parsing. C++ Modules offers a promising way to improve ROOT's runtime
performance by saving the C++ header parsing time which happens during ROOT
runtime. This paper presents the results and challenges of integrating C++
Modules into ROOT.Comment: 8 pages, 3 figures, 6 listing, CHEP 2018 - 23rd International
Conference on Computing in High Energy and Nuclear Physic