Python 3.4.1 (default, Jun 30 2014, 00:39:13) [GCC 4.8.3] on linux Type "help", "copyright", "credits" or "license" for more information. >>> import couchdb >>> server = couchdb.Server('http://root:relax@localhost:5984') >>> server.config() Traceback (most recent call last): File "<stdin>", line 1, in <module> File "/usr/local/opt/virtualenv/couchdb3k/lib/python3.4/site-packages/couchdb/client.py", line 153, in config status, headers, data = self.resource.get_json('_config') File "/usr/local/opt/virtualenv/couchdb3k/lib/python3.4/site-packages/couchdb/http.py", line 555, in get_json return self._request_json('GET', path, headers=headers, **params) File "/usr/local/opt/virtualenv/couchdb3k/lib/python3.4/site-packages/couchdb/http.py", line 578, in _request_json headers=headers, **params) File "/usr/local/opt/virtualenv/couchdb3k/lib/python3.4/site-packages/couchdb/http.py", line 574, in _request credentials=self.credentials) File "/usr/local/opt/virtualenv/couchdb3k/lib/python3.4/site-packages/couchdb/http.py", line 302, in request authorization = basic_auth(credentials) File "/usr/local/opt/virtualenv/couchdb3k/lib/python3.4/site-packages/couchdb/http.py", line 610, in basic_auth return 'Basic %s' % b64encode('%s:%s' % credentials) File "/usr/local/opt/virtualenv/couchdb3k/lib64/python3.4/base64.py", line 62, in b64encode encoded = binascii.b2a_base64(s)[:-1] TypeError: 'str' does not support the buffer interface

I pushed a modified version of your fix as r4715ee910e9c (you had not actually run your doctests against 2.7, it seems). Thanks!