diff --git a/zuul/lib/clonemapper.py b/zuul/lib/clonemapper.py
index ae558cd..57ac177 100644
--- a/zuul/lib/clonemapper.py
+++ b/zuul/lib/clonemapper.py
@@ -19,6 +19,9 @@
 import os
 import re
 
+import six
+
+
 OrderedDict = extras.try_imports(['collections.OrderedDict',
                                   'ordereddict.OrderedDict'])
 
@@ -59,17 +62,17 @@
             raise Exception("Expansion error. Check error messages above")
 
         self.log.info("Mapping projects to workspace...")
-        for project, dest in ret.iteritems():
+        for project, dest in six.iteritems(ret):
             dest = os.path.normpath(os.path.join(workspace, dest[0]))
             ret[project] = dest
             self.log.info("  %s -> %s", project, dest)
 
         self.log.debug("Checking overlap in destination directories...")
         check = defaultdict(list)
-        for project, dest in ret.iteritems():
+        for project, dest in six.iteritems(ret):
             check[dest].append(project)
 
-        dupes = dict((d, p) for (d, p) in check.iteritems() if len(p) > 1)
+        dupes = dict((d, p) for (d, p) in six.iteritems(check) if len(p) > 1)
         if dupes:
             raise Exception("Some projects share the same destination: %s",
                             dupes)
diff --git a/zuul/lib/cloner.py b/zuul/lib/cloner.py
index f0235a6..3155df6 100644
--- a/zuul/lib/cloner.py
+++ b/zuul/lib/cloner.py
@@ -19,6 +19,8 @@
 import re
 import yaml
 
+import six
+
 from git import GitCommandError
 from zuul.lib.clonemapper import CloneMapper
 from zuul.merger.merger import Repo
@@ -62,7 +64,7 @@
         dests = mapper.expand(workspace=self.workspace)
 
         self.log.info("Preparing %s repositories", len(dests))
-        for project, dest in dests.iteritems():
+        for project, dest in six.iteritems(dests):
             self.prepareRepo(project, dest)
         self.log.info("Prepared all repositories")