Inja
A Template Engine for Modern C++
...Most importantly, inja needs only two header files, which is (nearly) as trivial as integration in C++ can get. Of course, everything is tested on all relevant compilers. Inja is a headers only library, which can be downloaded from the releases or directly from the include/ or single_include/ folder. Inja uses nlohmann/json.hpp as its single dependency, so make sure it can be included from inja.hpp. json can be downloaded here.