diff --git a/simplejson/scanner.py b/simplejson/scanner.py
new file mode 100644
index 0000000..54593a3
--- /dev/null
+++ b/simplejson/scanner.py
@@ -0,0 +1,77 @@
+"""JSON token scanner
+"""
+import re
+def _import_c_make_scanner():
+    try:
+        from simplejson._speedups import make_scanner
+        return make_scanner
+    except ImportError:
+        return None
+c_make_scanner = _import_c_make_scanner()
+
+__all__ = ['make_scanner']
+
+NUMBER_RE = re.compile(
+    r'(-?(?:0|[1-9]\d*))(\.\d+)?([eE][-+]?\d+)?',
+    (re.VERBOSE | re.MULTILINE | re.DOTALL))
+
+def py_make_scanner(context):
+    parse_object = context.parse_object
+    parse_array = context.parse_array
+    parse_string = context.parse_string
+    match_number = NUMBER_RE.match
+    encoding = context.encoding
+    strict = context.strict
+    parse_float = context.parse_float
+    parse_int = context.parse_int
+    parse_constant = context.parse_constant
+    object_hook = context.object_hook
+    object_pairs_hook = context.object_pairs_hook
+    memo = context.memo
+
+    def _scan_once(string, idx):
+        try:
+            nextchar = string[idx]
+        except IndexError:
+            raise StopIteration
+
+        if nextchar == '"':
+            return parse_string(string, idx + 1, encoding, strict)
+        elif nextchar == '{':
+            return parse_object((string, idx + 1), encoding, strict,
+                _scan_once, object_hook, object_pairs_hook, memo)
+        elif nextchar == '[':
+            return parse_array((string, idx + 1), _scan_once)
+        elif nextchar == 'n' and string[idx:idx + 4] == 'null':
+            return None, idx + 4
+        elif nextchar == 't' and string[idx:idx + 4] == 'true':
+            return True, idx + 4
+        elif nextchar == 'f' and string[idx:idx + 5] == 'false':
+            return False, idx + 5
+
+        m = match_number(string, idx)
+        if m is not None:
+            integer, frac, exp = m.groups()
+            if frac or exp:
+                res = parse_float(integer + (frac or '') + (exp or ''))
+            else:
+                res = parse_int(integer)
+            return res, m.end()
+        elif nextchar == 'N' and string[idx:idx + 3] == 'NaN':
+            return parse_constant('NaN'), idx + 3
+        elif nextchar == 'I' and string[idx:idx + 8] == 'Infinity':
+            return parse_constant('Infinity'), idx + 8
+        elif nextchar == '-' and string[idx:idx + 9] == '-Infinity':
+            return parse_constant('-Infinity'), idx + 9
+        else:
+            raise StopIteration
+
+    def scan_once(string, idx):
+        try:
+            return _scan_once(string, idx)
+        finally:
+            memo.clear()
+
+    return scan_once
+
+make_scanner = c_make_scanner or py_make_scanner