See the PGP Information page for information on validating source releases.
Free binaries are available elsewhere - search Google to find them.
We do not provide binaries for macOS since newer releases of CUPS are not generally compatible with prior releases of macOS, and System Integrity Protection (enabled by default) will prevent replacement of the CUPS software.
The source distributions include an RPM spec file that can be used to build RPM packages for your Linux distribution. The rpmbuild command is used to build from the tar files:
rpmbuild -ta cups-version-source.tar.gz
At a minimum, you'll need the gcc, pam-devel, and zlib-devel packages installed to compile CUPS with all of the standard functionality. Additional developer packages are needed for Bonjour, DBUS, systemd, and USB printing support.
The spec file supports five options:
For example, if you are compiling CUPS on Red Hat Enterprise Linux 6, you will need to provide the --without systemd option since that distribution does not use systemd:
rpmbuild -ta cups-version-source.tar.gz --without systemd
Public access to the CUPS repository is now provided via GIT. Run the following command to checkout the current 2.2 (development) version of the CUPS code:
git clone https://github.com/apple/cups.git cups-2.2
Choose the "branch-2.1" branch to checkout the current 2.1.x (stable) version of the CUPS code:
git clone -b branch-2.1 https://github.com/apple/cups.git cups-2.1