[Distutils] manylinux1 guidelines for zlib?

Hello, Surprisingly, the manylinux1 spec doesn't seem to include the zlib in the list of known-to-be-available libraries (are there GNU/Linux systems out there without a zlib installed?). Since I'm assuming several packages already had a need for that, is there a recommended way to link in the zlib as part of a manylinux1 wheel? Would you recommend static linking with a private version, or dynamic linking? Regards Antoine.