Abstract-Make is one of the oldest build technologies and is still widely used today, whether by manually writing Makefiles, or by generating them using tools like Autotools and CMake. Despite its conceptual simplicity, modern Make implementations such as GNU Make have become very complex languages, featuring functions, macros, lazy variable assignments and (in GNU Make 4.0) the Guile embedded scripting language. Since we are interested in understanding how widespread such complex language features are, this paper studies the use of Make features in almost 20,000 Makefiles, comprised of over 8.4 million lines, from more than 350 different open source projects. We look at the popularity of features and the difference between hand-written Makefiles and those generated using various tools. We find that generated Makefiles use only a core set of features and that more advanced features (such as function calls) are used very little, and almost exclusively in hand-written Makefiles.