The standard environment is used by passing it as an input called stdenv to the derivation, and then doing source $stdenv/setup at the top of the builder. Apart from adding the aforementioned commands to the PATH, setup also does the following: All input packages specified in the buildInputs environment variable have their /bin subdirectory added to PATH, their /include subdirectory added to the C/C++ header file search path, and their /lib subdirectory added to the linker search path. This can be extended. For instance, when the pkgconfig package is used, the subdirectory /lib/pkgconfig of each input is added to the PKG_CONFIG_PATH environment variable. The environment variable NIX_CFLAGS_STRIP is set so that the compiler strips debug information from object files. This can be disabled by setting NIX_STRIP_DEBUG to 0. The setup script also exports a function called genericBuild that knows how to build typical Autoconf-style packages. It can be customised to perform builds for any type of package. It is advisable to use genericBuild since it provides facilities that are almost always useful such as unpacking of sources, patching of sources, nested logging, etc. The definitive, up-to-date documentation of the generic builder is the source itself, which resides in pkgs/stdenv/generic/setup.sh.