diff --git a/esphomeyaml/api/client.py b/esphomeyaml/api/client.py
index 53608a3082..446de042b5 100644
--- a/esphomeyaml/api/client.py
+++ b/esphomeyaml/api/client.py
@@ -14,7 +14,7 @@ import esphomeyaml.api.api_pb2 as pb
 from esphomeyaml.const import CONF_PASSWORD, CONF_PORT
 from esphomeyaml.core import EsphomeyamlError
 from esphomeyaml.helpers import resolve_ip_address, indent, color
-from esphomeyaml.py_compat import text_type, IS_PY2, byte, char, format_bytes
+from esphomeyaml.py_compat import text_type, IS_PY2, byte_to_bytes, char_to_byte, format_bytes
 from esphomeyaml.util import safe_print
 
 _LOGGER = logging.getLogger(__name__)
@@ -67,16 +67,16 @@ MESSAGE_TYPE_TO_PROTO = {
 
 def _varuint_to_bytes(value):
     if value <= 0x7F:
-        return byte(value)
+        return byte_to_bytes(value)
 
     ret = bytes()
     while value:
         temp = value & 0x7F
         value >>= 7
         if value:
-            ret += byte(temp | 0x80)
+            ret += byte_to_bytes(temp | 0x80)
         else:
-            ret += byte(temp)
+            ret += byte_to_bytes(temp)
 
     return ret
 
@@ -85,7 +85,7 @@ def _bytes_to_varuint(value):
     result = 0
     bitpos = 0
     for c in value:
-        val = char(c)
+        val = char_to_byte(c)
         result |= (val & 0x7F) << bitpos
         bitpos += 7
         if (val & 0x80) == 0:
@@ -361,7 +361,7 @@ class APIClient(threading.Thread):
 
     def _recv_varint(self):
         raw = bytes()
-        while not raw or char(raw[-1]) & 0x80:
+        while not raw or char_to_byte(raw[-1]) & 0x80:
             raw += self._recv(1)
         return _bytes_to_varuint(raw)
 
@@ -370,7 +370,7 @@ class APIClient(threading.Thread):
             return
 
         # Preamble
-        if char(self._recv(1)[0]) != 0x00:
+        if char_to_byte(self._recv(1)[0]) != 0x00:
             raise APIConnectionError("Invalid preamble")
 
         length = self._recv_varint()
diff --git a/esphomeyaml/components/font.py b/esphomeyaml/components/font.py
index ab1611231e..c69ffbd46e 100644
--- a/esphomeyaml/components/font.py
+++ b/esphomeyaml/components/font.py
@@ -8,6 +8,7 @@ from esphomeyaml.const import CONF_FILE, CONF_GLYPHS, CONF_ID, CONF_SIZE
 from esphomeyaml.core import CORE, HexInt
 from esphomeyaml.cpp_generator import ArrayInitializer, MockObj, Pvariable, RawExpression, add
 from esphomeyaml.cpp_types import App
+from esphomeyaml.py_compat import sort_by_cmp
 
 DEPENDENCIES = ['display']
 MULTI_CONF = True
@@ -37,7 +38,7 @@ def validate_glyphs(value):
             return 1
         raise vol.Invalid(u"Found duplicate glyph {}".format(x))
 
-    value.sort(cmp=comparator)
+    sort_by_cmp(value, comparator)
     return value
 
 
diff --git a/esphomeyaml/espota2.py b/esphomeyaml/espota2.py
index 423fc6a5bd..b541f4d63b 100755
--- a/esphomeyaml/espota2.py
+++ b/esphomeyaml/espota2.py
@@ -7,7 +7,7 @@ import time
 
 from esphomeyaml.core import EsphomeyamlError
 from esphomeyaml.helpers import resolve_ip_address, is_ip_address
-from esphomeyaml.py_compat import IS_PY2, char
+from esphomeyaml.py_compat import IS_PY2, char_to_byte
 
 RESPONSE_OK = 0
 RESPONSE_REQUEST_AUTH = 1
@@ -68,7 +68,7 @@ def recv_decode(sock, amount, decode=True):
     data = sock.recv(amount)
     if not decode:
         return data
-    return [char(x) for x in data]
+    return [char_to_byte(x) for x in data]
 
 
 def receive_exactly(sock, amount, msg, expect, decode=True):
diff --git a/esphomeyaml/helpers.py b/esphomeyaml/helpers.py
index b7afe6cfca..b13b9768e1 100644
--- a/esphomeyaml/helpers.py
+++ b/esphomeyaml/helpers.py
@@ -6,7 +6,7 @@ import os
 import socket
 import subprocess
 
-from esphomeyaml.py_compat import text_type, IS_PY2
+from esphomeyaml.py_compat import text_type, char_to_byte
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -41,13 +41,19 @@ def indent(text, padding=u'  '):
 
 # From https://stackoverflow.com/a/14945195/8924614
 def cpp_string_escape(string, encoding='utf-8'):
+    def _should_escape(byte):  # type: (int) -> bool
+        if not 32 <= byte < 127:
+            return True
+        if byte in (char_to_byte('\\'), char_to_byte('"')):
+            return True
+        return False
+
     if isinstance(string, text_type):
         string = string.encode(encoding)
     result = ''
     for character in string:
-        if IS_PY2:
-            character = ord(character)
-        if not (32 <= character < 127) or character in ('\\', '"'):
+        character = char_to_byte(character)
+        if _should_escape(character):
             result += '\\%03o' % character
         else:
             result += chr(character)
diff --git a/esphomeyaml/py_compat.py b/esphomeyaml/py_compat.py
index 5e70766c46..5147749efa 100644
--- a/esphomeyaml/py_compat.py
+++ b/esphomeyaml/py_compat.py
@@ -1,3 +1,4 @@
+import functools
 import sys
 
 PYTHON_MAJOR = sys.version_info[0]
@@ -25,18 +26,28 @@ else:
     binary_type = bytes
 
 
-def byte(val):
+def byte_to_bytes(val):  # type: (int) -> bytes
     if IS_PY2:
         return chr(val)
     else:
         return bytes([val])
 
 
-def char(val):
+def char_to_byte(val):  # type: (str) -> int
     if IS_PY2:
-        return ord(val)
+        if isinstance(val, string_types):
+            return ord(val)
+        elif isinstance(val, int):
+            return val
+        else:
+            raise ValueError
     else:
-        return val
+        if isinstance(val, str):
+            return ord(val)
+        elif isinstance(val, int):
+            return val
+        else:
+            raise ValueError
 
 
 def format_bytes(val):
@@ -44,3 +55,10 @@ def format_bytes(val):
         return ' '.join('{:02X}'.format(ord(x)) for x in val)
     else:
         return ' '.join('{:02X}'.format(x) for x in val)
+
+
+def sort_by_cmp(list_, cmp):
+    if IS_PY2:
+        list_.sort(cmp=cmp)
+    else:
+        list_.sort(key=functools.cmp_to_key(cmp))