The slapos.networkcache should not be required, buildout should work without such library.

src/zc/buildout/networkcache.py

@@ -19,8 +19,6 @@ import posixpath
 import re
 import urllib
 import urlparse
-from slapos.libnetworkcache import NetworkcacheClient, UploadError, \
-                                   DirectoryNotFound
 
 
 _md5_re = re.compile(r'md5=([a-f0-9]+)')
@@ -54,6 +52,13 @@ def download_network_cached(sha_dir, sha_cache, path, url, logger, md5sum=None):
 
     return True if download succeeded.
     """
+    try:
+      from slapos.libnetworkcache import NetworkcacheClient, UploadError, \
+                                   DirectoryNotFound
+    except:
+      return False
+
+
     if sha_cache in (None, '',):
         # Not able to use network cache
         return False
@@ -89,6 +94,12 @@ def download_network_cached(sha_dir, sha_cache, path, url, logger, md5sum=None):
 
 def upload_network_cached(sha_cache, sha_dir, external_url, path, logger):
     """Upload file to a shacache server"""
+    try:
+      from slapos.libnetworkcache import NetworkcacheClient, UploadError, \
+                                   DirectoryNotFound
+    except:
+      return False
+
     if sha_cache in [None, ''] or sha_dir in [None, '']:
         logger.debug(
              'Upload cache ignored, shacache or shadir was not provided!')