diff --git a/src/kapidox/depdiagram/framework.py b/src/kapidox/depdiagram/framework.py
--- a/src/kapidox/depdiagram/framework.py
+++ b/src/kapidox/depdiagram/framework.py
@@ -22,6 +22,9 @@
 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 # THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+from functools import reduce
+
 class Framework(object):
     """
     A framework has a tier, a name, a collection of targets it provides.
diff --git a/src/kapidox/depdiagram/frameworkdb.py b/src/kapidox/depdiagram/frameworkdb.py
--- a/src/kapidox/depdiagram/frameworkdb.py
+++ b/src/kapidox/depdiagram/frameworkdb.py
@@ -164,14 +164,13 @@
         for dot_file in dot_files:
             yaml_file = dot_file.replace(".dot", ".yaml")
             with open(yaml_file) as f:
-                dct = yaml.load(f)
+                dct = yaml.safe_load(f)
 
             if 'tier' not in dct:
                 # This mean it's not a frameworks
                 continue
 
             tier = dct["tier"]
-            dot_file = dot_file.encode("utf-8")
             fw = parser.parse(tier, dot_file)
 
             _add_extra_dependencies(fw, dct)
diff --git a/src/kapidox/depdiagram/generate.py b/src/kapidox/depdiagram/generate.py
--- a/src/kapidox/depdiagram/generate.py
+++ b/src/kapidox/depdiagram/generate.py
@@ -24,6 +24,7 @@
 # THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 import logging
 import itertools
+from functools import cmp_to_key
 
 from kapidox.depdiagram.block import Block, quote
 from kapidox.depdiagram.framework import Framework
@@ -112,7 +113,7 @@
                     # depend on other frameworks from that tier are listed after
                     # their dependees.
                     frameworks = list(frameworks)
-                    for fw in sorted(frameworks, cmp=FrameworkCmp(self.db)):
+                    for fw in sorted(frameworks, key=cmp_to_key(FrameworkCmp(self.db))):
                         if self.detailed:
                             self.write_detailed_framework(tier_block, fw)
                         else:
diff --git a/src/kapidox/depdiagram/gvutils.py b/src/kapidox/depdiagram/gvutils.py
--- a/src/kapidox/depdiagram/gvutils.py
+++ b/src/kapidox/depdiagram/gvutils.py
@@ -42,11 +42,11 @@
 
     @property
     def label(self):
-        return gv.getv(self.handle, b"label")
+        return gv.getv(self.handle, "label")
 
     @property
     def shape(self):
-        return gv.getv(self.handle, b"shape")
+        return gv.getv(self.handle, "shape")
 
 
 class Edge(object):
diff --git a/src/kapidox/preprocessing.py b/src/kapidox/preprocessing.py
--- a/src/kapidox/preprocessing.py
+++ b/src/kapidox/preprocessing.py
@@ -108,7 +108,7 @@
         return None
 
     try:
-        metainfo = yaml.load(open(metainfo_file))
+        metainfo = yaml.safe_load(open(metainfo_file))
     except Exception as e:
         print(e)
         logging.warning('Could not load metainfo.yaml for {}, skipping it'