diff --git a/src/calibre/utils/terminal.py b/src/calibre/utils/terminal.py
index 97fb08bac5..599d112ad3 100644
--- a/src/calibre/utils/terminal.py
+++ b/src/calibre/utils/terminal.py
@@ -9,8 +9,8 @@ __docformat__ = 'restructuredtext en'
 
 import os, sys, re
 
-from calibre.constants import iswindows
-from polyglot.builtins import iteritems, range, zip
+from calibre.constants import iswindows, ispy3
+from polyglot.builtins import iteritems, range, zip, native_string_type
 
 if iswindows:
     import ctypes.wintypes
@@ -26,7 +26,7 @@ if iswindows:
 
 
 def fmt(code):
-    return ('\033[%dm'%code).encode('ascii')
+    return '\033[%dm' % code
 
 
 RATTRIBUTES = dict(
@@ -96,11 +96,11 @@ def colored(text, fg=None, bg=None, bold=False):
         prefix.append(BACKGROUNDS[bg])
     if bold:
         prefix.append(ATTRIBUTES['bold'])
-    prefix = b''.join(prefix)
+    prefix = ''.join(prefix)
     suffix = RESET
-    if isinstance(text, type(u'')):
-        prefix = prefix.decode('ascii')
-        suffix = suffix.decode('ascii')
+    if isinstance(text, bytes):
+        prefix = prefix.encode('ascii')
+        suffix = suffix.encode('ascii')
     return prefix + text + suffix
 
 
@@ -128,7 +128,7 @@ class Detect(object):
                     # Stream is a console
                     self.set_console = windll.kernel32.SetConsoleTextAttribute
                     self.default_console_text_attributes = WCOLORS['white']
-                    kernel32 = WinDLL(b'kernel32', use_last_error=True)
+                    kernel32 = WinDLL(native_string_type('kernel32'), use_last_error=True)
                     self.write_console = kernel32.WriteConsoleW
                     self.write_console.argtypes = [wintypes.HANDLE, wintypes.c_wchar_p, wintypes.DWORD, POINTER(wintypes.DWORD), wintypes.LPVOID]
                     self.write_console.restype = wintypes.BOOL
@@ -151,9 +151,13 @@ class Detect(object):
             while text:
                 t, text = text[:chunk], text[chunk:]
                 wt = c_wchar_p(t)
-                # Use the fact that len(t) == wcslen(wt) in python 2.7 on
-                # windows where the python unicode type uses UTF-16
-                if not self.write_console(self.file_handle, wt, len(t), byref(written), None):
+                if ispy3:
+                    text_len = len(t.encode('utf-16'))
+                else:
+                    # Use the fact that len(t) == wcslen(wt) in python 2.7 on
+                    # windows where the python unicode type uses UTF-16
+                    text_len = len(t)
+                if not self.write_console(self.file_handle, wt, text_len, byref(written), None):
                     # Older versions of windows can fail to write large strings
                     # to console with WriteConsoleW (seen it happen on Win XP)
                     import winerror
@@ -217,17 +221,27 @@ class ColoredStream(Detect):
 
 class ANSIStream(Detect):
 
-    ANSI_RE = re.compile(br'\033\[((?:\d|;)*)([a-zA-Z])')
+    ANSI_RE = r'\033\[((?:\d|;)*)([a-zA-Z])'
 
     def __init__(self, stream=None):
         super(ANSIStream, self).__init__(stream)
         self.encoding = getattr(self.stream, 'encoding', 'utf-8') or 'utf-8'
+        self.stream_takes_unicode = hasattr(self.stream, 'buffer')
         self.last_state = (None, None, False)
+        self._ansi_re_bin = self._ansi_re_unicode = None
+
+    def ansi_re(self, binary=False):
+        attr = '_ansi_re_bin' if binary else '_ansi_re_unicode'
+        ans = getattr(self, attr)
+        if ans is None:
+            expr = self.ANSI_RE
+            if binary:
+                expr = expr.encode('ascii')
+            ans = re.compile(expr)
+            setattr(self, attr, ans)
+        return ans
 
     def write(self, text):
-        if isinstance(text, type(u'')):
-            text = text.encode(self.encoding, 'replace')
-
         if not self.isatty:
             return self.strip_and_write(text)
 
@@ -239,8 +253,22 @@ class ANSIStream(Detect):
 
         self.write_and_convert(text)
 
+    def polyglot_write(self, text):
+        binary = isinstance(text, bytes)
+        stream = self.stream
+        if self.stream_takes_unicode:
+            if binary:
+                stream = self.stream.buffer
+        else:
+            if not binary:
+                text = text.encode(self.encoding, 'replace')
+        stream.write(text)
+
     def strip_and_write(self, text):
-        self.stream.write(self.ANSI_RE.sub(b'', text))
+        binary = isinstance(text, bytes)
+        pat = self.ansi_re(binary)
+        repl = b'' if binary else ''
+        self.polyglot_write(pat.sub(repl, text))
 
     def write_and_convert(self, text):
         '''
@@ -249,7 +277,8 @@ class ANSIStream(Detect):
         calls.
         '''
         cursor = 0
-        for match in self.ANSI_RE.finditer(text):
+        binary = isinstance(text, bytes)
+        for match in self.ansi_re(binary).finditer(text):
             start, end = match.span()
             self.write_plain_text(text, cursor, start)
             self.convert_ansi(*match.groups())
@@ -268,21 +297,25 @@ class ANSIStream(Detect):
                     pass
                 else:
                     return self.write_unicode_text(utext)
-            self.stream.write(text)
+            self.polyglot_write(text)
 
     def convert_ansi(self, paramstring, command):
+        if isinstance(paramstring, bytes):
+            paramstring = paramstring.decode('ascii', 'replace')
+        if isinstance(command, bytes):
+            command = command.decode('ascii', 'replace')
         params = self.extract_params(paramstring)
         self.call_win32(command, params)
 
     def extract_params(self, paramstring):
         def split(paramstring):
-            for p in paramstring.split(b';'):
+            for p in paramstring.split(';'):
                 if p:
                     yield int(p)
         return tuple(split(paramstring))
 
     def call_win32(self, command, params):
-        if command != b'm':
+        if command != 'm':
             return
         fg, bg, bold = self.last_state
 
diff --git a/src/polyglot/builtins.py b/src/polyglot/builtins.py
index d70a207da8..6616d5173c 100644
--- a/src/polyglot/builtins.py
+++ b/src/polyglot/builtins.py
@@ -7,6 +7,7 @@ from __future__ import absolute_import, division, print_function, unicode_litera
 import sys
 
 is_py3 = sys.version_info.major >= 3
+native_string_type = str
 
 
 def iterkeys(d):