diff --git a/isso/tests/test_html.py b/isso/tests/test_html.py
index b1be6dc..a036eb3 100644
--- a/isso/tests/test_html.py
+++ b/isso/tests/test_html.py
@@ -33,7 +33,7 @@ class TestHTML(unittest.TestCase):
             self.assertEqual(convert(input), expected)
 
     def test_github_flavoured_markdown(self):
-        convert = html.Markdown(extensions=("fenced_code", ))
+        convert = html.Markdown(extensions=("fenced-code", ))
 
         # without lang
         _in = textwrap.dedent("""\
diff --git a/isso/utils/html.py b/isso/utils/html.py
index 51c01e8..5e2c148 100644
--- a/isso/utils/html.py
+++ b/isso/utils/html.py
@@ -59,11 +59,11 @@ def sanitize(tokenizer, document):
     return serializer.render(stream)
 
 
-def Markdown(extensions=("strikethrough", "superscript", "autolink")):
+def Markdown(extensions=("strikethrough", "superscript", "autolink",
+                         "fenced-code")):
 
-    flags = reduce(operator.xor, map(
-        lambda ext: getattr(misaka, 'EXT_' + ext.upper()), extensions), 0)
-    md = misaka.Markdown(Unofficial(), extensions=flags)
+    renderer = Unofficial()
+    md = misaka.Markdown(renderer, extensions=extensions)
 
     def inner(text):
         rv = md(text).rstrip("\n")
@@ -82,7 +82,7 @@ class Unofficial(misaka.HtmlRenderer):
     to <code class="$lang">, compatible with Highlight.js.
     """
 
-    def block_code(self, text, lang):
+    def blockcode(self, text, lang):
         lang = ' class="{0}"'.format(lang) if lang else ''
         return "<pre><code{1}>{0}</code></pre>\n".format(text, lang)