You will need a compiler that supports C++ 17. I used GCC 7.4.0c.
The code is on GitHub at https://github.com/PacktPublishing/Hands-On-Functional-Programming-with-Cpp in the Chapter15 folder. It includes and uses doctest, which is a single-header open source unit testing library. You can find it on its GitHub repository here: https://github.com/onqtam/doctest.