title: bcrypt in python
body: <p>At the moment I'm trying to build a log in system with a very high security.</p>
  
  <p>So I want to use bcrypt and I've also found a 3rd party library, 
  <a href="http://www.mindrot.org/projects/py-bcrypt/" rel="noreferrer">py-bcrypt</a>.</p>
  
  <p>But the author said it is a pure python implementation. </p>
  
  <p>Now I read somewhere that it is not recommended to use bcrypt in python only because it is too slow and this results in a security leak. bcrypt should be implemented in C.</p>
  
  <p>Can anyone confirm this?  Now what should I do?</p>
  
  <p><strong>Should I use:</strong></p>
  
  <ul>
  <li>bcrypt (python)</li>
  <li>SHA512 (from hashlib)</li>
  <li>something different</li>
  </ul>
  
  <p><em>I'm using Google App Engine</em></p>
  
  <p><strong>EDIT:</strong>
  <a href="http://packages.python.org/passlib/lib/passlib.hash.bcrypt.html#bcrypt-backends" rel="noreferrer">http://packages.python.org/passlib/lib/passlib.hash.bcrypt.html#bcrypt-backends</a></p>
  
  <blockquote>
    <p>It should be noted that the pure-python implementation (#4) is too
    slow to be useable, given the number of rounds currently required for
    security. Because of this, it is disabled by default, unless the
    environment variable PASSLIB_BUILTIN_BCRYPT="enabled" is set.</p>
  </blockquote>