Frequently asked questions
==========================

How does ``cryptography`` compare to NaCl (Networking and Cryptography Library)?
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While ``cryptography`` and `NaCl`_ both share the goal of making cryptography
easier, and safer, to use for developers, ``cryptography`` is designed to be a
general purpose library, interoperable with existing systems, while NaCl
features a collection of hand selected algorithms.

``cryptography``'s :ref:`recipes <cryptography-layout>` layer has similar goals
to NaCl.

If you prefer NaCl's design, we highly recommend `PyNaCl`_.

Compiling ``cryptography`` on OS X produces a ``fatal error: 'openssl/aes.h' file not found`` error
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This happens because OS X 10.11 no longer includes a copy of OpenSSL.
``cryptography`` now provides wheels which include a statically linked copy of
OpenSSL. You're seeing this error because your copy of pip is too old to find
our wheel files. Upgrade your copy of pip with ``pip install -U pip`` and then
try install ``cryptography`` again.

.. _`NaCl`: https://nacl.cr.yp.to/
.. _`PyNaCl`: https://pynacl.readthedocs.org