make -j
'-j' will try to run as many subprocesses as possible. You can limit it by adding a number, for example 'make -j 4' might be a good one.
If you try this out on a project containing many files to compile, and if you have a machine which can run multiple flows of execution in parallel, you should get a much faster build as the files are compiled in parallel.
In the rest of the tutorial we'll learn how gnustep-make decides which steps are done in parallel and which steps are done in serial order.