CISTEM is a stemming algorithm for the German language, the algorithm is available for different languages at https://github.com/LeonieWeissweiler/CISTEM. The R package cistem contains an interface to the 'C++' version of the code.

• TODO: cistem.cpp sets the locale to setlocale(LC_ALL, "de_DE.UTF-8") which is the reason why it is currently not accepted on CRAN. An easy fix could be to remove this line from the C++ code an check on the startup if the correct locale is set and if not issue a warning.