diff --git a/webagg/liverec.py b/webagg/liverec.py
index 5d8bacf0..e0fe1298 100644
--- a/webagg/liverec.py
+++ b/webagg/liverec.py
@@ -42,7 +42,7 @@ class RecordingStream(object):
         self.recorder.write_response_buff(buff)
         return res
 
-    def readline(self, maxlen=None):
+    def readline(self, maxlen=-1):
         line = self.fp.readline(maxlen)
         self.recorder.write_response_header_line(line)
         return line
diff --git a/webagg/responseloader.py b/webagg/responseloader.py
index 0bacb440..96e64067 100644
--- a/webagg/responseloader.py
+++ b/webagg/responseloader.py
@@ -12,10 +12,11 @@ from io import BytesIO
 from bottle import response
 
 import uuid
+import six
 
 
 #=============================================================================
-class StreamIter(object):
+class StreamIter(six.Iterator):
     def __init__(self, stream, header=None, size=8192):
         self.stream = stream
         self.header = header