diff --git a/jedi/api.py b/jedi/api.py
index 248991b4..5e7c1109 100644
--- a/jedi/api.py
+++ b/jedi/api.py
@@ -442,7 +442,7 @@ class Script(object):
         return match.groups()
 
     def __del__(self):
-        evaluate.clear_caches()
+        api_classes._clear_caches()
 
 
 def set_debug_function(func_cb=debug.print_to_stdout, warnings=True,
diff --git a/jedi/api_classes.py b/jedi/api_classes.py
index 367615a9..793f806a 100644
--- a/jedi/api_classes.py
+++ b/jedi/api_classes.py
@@ -3,6 +3,9 @@
 import re
 import os
 
+import cache
+import dynamic
+import helpers
 import settings
 import evaluate
 import imports
@@ -10,6 +13,20 @@ import parsing
 import keywords
 
 
+def _clear_caches():
+    """
+    Clears all caches of this and related modules. The only cache that will not
+    be deleted is the module cache.
+    """
+    cache.clear_caches()
+    dynamic.search_param_cache.clear()
+    helpers.ExecutionRecursionDecorator.reset()
+
+    evaluate.follow_statement.reset()
+
+    imports.imports_processed = 0
+
+
 class BaseDefinition(object):
     _mapping = {'posixpath': 'os.path',
                'riscospath': 'os.path',
@@ -193,7 +210,7 @@ class Completion(BaseDefinition):
 
             self._followed_definitions = \
                             [BaseDefinition(d, d.start_pos) for d in defs]
-            evaluate.clear_caches()
+            _clear_caches()
 
         return self._followed_definitions
 
diff --git a/jedi/cache.py b/jedi/cache.py
new file mode 100644
index 00000000..5d882fd9
--- /dev/null
+++ b/jedi/cache.py
@@ -0,0 +1,53 @@
+memoize_caches = []
+faked_scopes = []
+
+
+def clear_caches():
+    """ Jedi caches many things, that should be completed after each completion
+    finishes.
+    """
+    global memoize_caches, faked_scopes
+
+    # memorize_caches must never be deleted, because the dicts will get lost in
+    # the wrappers.
+    for m in memoize_caches:
+        m.clear()
+
+    faked_scopes = []  # TODO really needed anymore? weakrefs are gone...
+
+
+def memoize_default(default=None):
+    """ This is a typical memoization decorator, BUT there is one difference:
+    To prevent recursion it sets defaults.
+
+    Preventing recursion is in this case the much bigger use than speed. I
+    don't think, that there is a big speed difference, but there are many cases
+    where recursion could happen (think about a = b; b = a).
+    """
+    def func(function):
+        memo = {}
+        memoize_caches.append(memo)
+
+        def wrapper(*args, **kwargs):
+            key = (args, frozenset(kwargs.items()))
+            if key in memo:
+                return memo[key]
+            else:
+                memo[key] = default
+                rv = function(*args, **kwargs)
+                memo[key] = rv
+                return rv
+        return wrapper
+    return func
+
+
+class CachedMetaClass(type):
+    """ This is basically almost the same than the decorator above, it just
+    caches class initializations. I haven't found any other way, so I do it
+    with meta classes.
+    """
+    @memoize_default()
+    def __call__(self, *args, **kwargs):
+        return super(CachedMetaClass, self).__call__(*args, **kwargs)
+
+
diff --git a/jedi/docstrings.py b/jedi/docstrings.py
index 29bf0d29..b960b606 100644
--- a/jedi/docstrings.py
+++ b/jedi/docstrings.py
@@ -5,7 +5,7 @@ import re
 import evaluate
 
 
-#@evaluate.memoize_default()  # TODO add
+#@cache.memoize_default()  # TODO add
 def follow_param(param):
     func = param.parent_function
     #print func, param, param.parent_function
diff --git a/jedi/dynamic.py b/jedi/dynamic.py
index 2e775462..83476186 100644
--- a/jedi/dynamic.py
+++ b/jedi/dynamic.py
@@ -9,6 +9,7 @@ from __future__ import with_statement
 
 import os
 
+import cache
 import parsing
 import modules
 import evaluate
@@ -93,7 +94,7 @@ class ParamListener(object):
         self.param_possibilities.append(params)
 
 
-@evaluate.memoize_default([])
+@cache.memoize_default([])
 def search_params(param):
     """
     This is a dynamic search for params. If you try to complete a type:
@@ -223,7 +224,7 @@ def dec(func):
 
 
 #@dec
-@evaluate.memoize_default([])
+@cache.memoize_default([])
 def _check_array_additions(compare_array, module, is_list):
     """
     Checks if a `parsing.Array` has "add" statements:
diff --git a/jedi/evaluate.py b/jedi/evaluate.py
index 5b3d2126..13e2f319 100644
--- a/jedi/evaluate.py
+++ b/jedi/evaluate.py
@@ -18,6 +18,7 @@ import sys
 import itertools
 import copy
 
+import cache
 import parsing
 import debug
 import builtin
@@ -26,9 +27,6 @@ import helpers
 import dynamic
 import docstrings
 
-memoize_caches = []
-faked_scopes = []
-
 
 class DecoratorNotFound(LookupError):
     """
@@ -63,66 +61,6 @@ class MultiLevelAttributeError(Exception):
         return 'Original:\n\n' + ''.join(tb)
 
 
-def clear_caches():
-    """
-    Clears all caches of this and related modules. Jedi caches many things,
-    that should be completed after each completion finishes. The only things
-    that stays is the module cache (which is not deleted here).
-    """
-    global memoize_caches, faked_scopes
-
-    for m in memoize_caches:
-        m.clear()
-
-    dynamic.search_param_cache.clear()
-    helpers.ExecutionRecursionDecorator.reset()
-
-    # memorize_caches must never be deleted, because the dicts will get lost in
-    # the wrappers.
-    faked_scopes = []
-
-    follow_statement.reset()
-
-    imports.imports_processed = 0
-
-
-def memoize_default(default=None):
-    """
-    This is a typical memoization decorator, BUT there is one difference:
-    To prevent recursion it sets defaults.
-
-    Preventing recursion is in this case the much bigger use than speed. I
-    don't think, that there is a big speed difference, but there are many cases
-    where recursion could happen (think about a = b; b = a).
-    """
-    def func(function):
-        memo = {}
-        memoize_caches.append(memo)
-
-        def wrapper(*args, **kwargs):
-            key = (args, frozenset(kwargs.items()))
-            if key in memo:
-                return memo[key]
-            else:
-                memo[key] = default
-                rv = function(*args, **kwargs)
-                memo[key] = rv
-                return rv
-        return wrapper
-    return func
-
-
-class CachedMetaClass(type):
-    """
-    This is basically almost the same than the decorator above, it just caches
-    class initializations. I haven't found any other way, so I do it with meta
-    classes.
-    """
-    @memoize_default()
-    def __call__(self, *args, **kwargs):
-        return super(CachedMetaClass, self).__call__(*args, **kwargs)
-
-
 class Executable(parsing.Base):
     """ An instance is also an executable - because __init__ is called """
     def __init__(self, base, var_args=None):
@@ -140,7 +78,7 @@ class Executable(parsing.Base):
         return self.base.parent
 
 
-class Instance(use_metaclass(CachedMetaClass, Executable)):
+class Instance(use_metaclass(cache.CachedMetaClass, Executable)):
     """ This class is used to evaluate instances. """
     def __init__(self, base, var_args=None):
         super(Instance, self).__init__(base, var_args)
@@ -159,7 +97,7 @@ class Instance(use_metaclass(CachedMetaClass, Executable)):
         # (No var_args) used.
         self.is_generated = False
 
-    @memoize_default()
+    @cache.memoize_default()
     def get_init_execution(self, func):
         func = InstanceElement(self, func, True)
         return Execution(func, self.var_args)
@@ -227,7 +165,7 @@ class Instance(use_metaclass(CachedMetaClass, Executable)):
         args = helpers.generate_param_array(v)
         return self.execute_subscope_by_name('__get__', args)
 
-    @memoize_default([])
+    @cache.memoize_default([])
     def get_defined_names(self):
         """
         Get the instance vars of a class. This includes the vars of all
@@ -273,7 +211,7 @@ class Instance(use_metaclass(CachedMetaClass, Executable)):
                 (type(self).__name__, self.base, len(self.var_args or []))
 
 
-class InstanceElement(use_metaclass(CachedMetaClass)):
+class InstanceElement(use_metaclass(cache.CachedMetaClass)):
     """
     InstanceElement is a wrapper for any object, that is used as an instance
     variable (e.g. self.variable or class methods).
@@ -288,7 +226,7 @@ class InstanceElement(use_metaclass(CachedMetaClass)):
         self.is_class_var = is_class_var
 
     @property
-    @memoize_default()
+    @cache.memoize_default()
     def parent(self):
         par = self.var.parent
         if isinstance(par, Class) and par == self.instance.base \
@@ -317,8 +255,8 @@ class InstanceElement(use_metaclass(CachedMetaClass)):
         par = InstanceElement(self.instance, origin.parent_stmt,
                                                     self.is_class_var)
         new.parent_stmt = par
-        faked_scopes.append(par)
-        faked_scopes.append(new)
+        cache.faked_scopes.append(par)
+        cache.faked_scopes.append(new)
         return new
 
     def __getattr__(self, name):
@@ -331,7 +269,7 @@ class InstanceElement(use_metaclass(CachedMetaClass)):
         return "<%s of %s>" % (type(self).__name__, self.var)
 
 
-class Class(use_metaclass(CachedMetaClass, parsing.Base)):
+class Class(use_metaclass(cache.CachedMetaClass, parsing.Base)):
     """
     This class is not only important to extend `parsing.Class`, it is also a
     important for descriptors (if the descriptor methods are evaluated or not).
@@ -339,7 +277,7 @@ class Class(use_metaclass(CachedMetaClass, parsing.Base)):
     def __init__(self, base):
         self.base = base
 
-    @memoize_default(default=[])
+    @cache.memoize_default(default=[])
     def get_super_classes(self):
         supers = []
         # TODO care for mro stuff (multiple super classes).
@@ -355,7 +293,7 @@ class Class(use_metaclass(CachedMetaClass, parsing.Base)):
             supers += get_scopes_for_name(builtin.Builtin.scope, 'object')
         return supers
 
-    @memoize_default(default=[])
+    @cache.memoize_default(default=[])
     def get_defined_names(self):
         def in_iterable(name, iterable):
             """ checks if the name is in the variable 'iterable'. """
@@ -397,7 +335,7 @@ class Class(use_metaclass(CachedMetaClass, parsing.Base)):
         return "<e%s of %s>" % (type(self).__name__, self.base)
 
 
-class Function(use_metaclass(CachedMetaClass, parsing.Base)):
+class Function(use_metaclass(cache.CachedMetaClass, parsing.Base)):
     """
     Needed because of decorators. Decorators are evaluated here.
     """
@@ -408,7 +346,7 @@ class Function(use_metaclass(CachedMetaClass, parsing.Base)):
         self.is_decorated = is_decorated
 
     @property
-    @memoize_default()
+    @cache.memoize_default()
     def _decorated_func(self):
         """
         Returns the function, that is to be executed in the end.
@@ -432,7 +370,7 @@ class Function(use_metaclass(CachedMetaClass, parsing.Base)):
                 # Create param array.
                 old_func = Function(f, is_decorated=True)
                 params = helpers.generate_param_array([old_func], old_func)
-                faked_scopes.append(old_func)
+                cache.faked_scopes.append(old_func)
 
                 wrappers = Execution(decorator, params).get_return_types()
                 if not len(wrappers):
@@ -481,7 +419,7 @@ class Execution(Executable):
     multiple calls to functions and recursion has to be avoided. But this is
     responsibility of the decorators.
     """
-    @memoize_default(default=[])
+    @cache.memoize_default(default=[])
     @helpers.ExecutionRecursionDecorator
     def get_return_types(self, evaluate_generator=False):
         """ Get the return types of a function. """
@@ -555,7 +493,7 @@ class Execution(Executable):
                 stmts += follow_statement(r)
             return stmts
 
-    @memoize_default(default=[])
+    @cache.memoize_default(default=[])
     def get_params(self):
         """
         This returns the params for an Execution/Instance and is injected as a
@@ -581,7 +519,7 @@ class Execution(Executable):
             new_param.is_generated = True
             name = copy.copy(param.get_name())
             name.parent = new_param
-            faked_scopes.append(new_param)
+            cache.faked_scopes.append(new_param)
             return name
 
         result = []
@@ -737,7 +675,7 @@ class Execution(Executable):
             if isinstance(copied, parsing.Function):
                 copied = Function(copied)
             objects.append(copied)
-            faked_scopes.append(copied)
+            cache.faked_scopes.append(copied)
         return objects
 
     def __getattr__(self, name):
@@ -745,7 +683,7 @@ class Execution(Executable):
             raise AttributeError('Tried to access %s: %s. Why?' % (name, self))
         return getattr(self.base, name)
 
-    @memoize_default()
+    @cache.memoize_default()
     def _scope_copy(self, scope):
         try:
             """ Copies a scope (e.g. if) in an execution """
@@ -758,28 +696,28 @@ class Execution(Executable):
             else:
                 copied = helpers.fast_parent_copy(scope)
                 copied.parent = self._scope_copy(copied.parent)
-                faked_scopes.append(copied)
+                cache.faked_scopes.append(copied)
                 return copied
         except AttributeError:
             raise MultiLevelAttributeError(sys.exc_info())
 
     @property
-    @memoize_default()
+    @cache.memoize_default()
     def returns(self):
         return self.copy_properties('returns')
 
     @property
-    @memoize_default()
+    @cache.memoize_default()
     def asserts(self):
         return self.copy_properties('asserts')
 
     @property
-    @memoize_default()
+    @cache.memoize_default()
     def statements(self):
         return self.copy_properties('statements')
 
     @property
-    @memoize_default()
+    @cache.memoize_default()
     def subscopes(self):
         return self.copy_properties('subscopes')
 
@@ -791,7 +729,7 @@ class Execution(Executable):
                 (type(self).__name__, self.base)
 
 
-class Generator(use_metaclass(CachedMetaClass, parsing.Base)):
+class Generator(use_metaclass(cache.CachedMetaClass, parsing.Base)):
     """ Cares for `yield` statements. """
     def __init__(self, func, var_args):
         super(Generator, self).__init__()
@@ -830,7 +768,7 @@ class Generator(use_metaclass(CachedMetaClass, parsing.Base)):
         return "<%s of %s>" % (type(self).__name__, self.func)
 
 
-class Array(use_metaclass(CachedMetaClass, parsing.Base)):
+class Array(use_metaclass(cache.CachedMetaClass, parsing.Base)):
     """
     Used as a mirror to parsing.Array, if needed. It defines some getter
     methods which are important in this module.
@@ -1380,7 +1318,7 @@ def assign_tuples(tup, results, seek_name):
 
 
 @helpers.RecursionDecorator
-@memoize_default(default=[])
+@cache.memoize_default(default=[])
 def follow_statement(stmt, seek_name=None):
     """
     The starting point of the completion. A statement always owns a call list,
diff --git a/jedi/helpers.py b/jedi/helpers.py
index b1f6e4c7..91a567e0 100644
--- a/jedi/helpers.py
+++ b/jedi/helpers.py
@@ -1,6 +1,7 @@
 import copy
 import contextlib
 
+import cache
 import parsing
 import evaluate
 import debug
@@ -195,7 +196,7 @@ def generate_param_array(args_tuple, parent_stmt=None):
             values.append([arg])
     pos = None
     arr = parsing.Array(pos, parsing.Array.TUPLE, parent_stmt, values=values)
-    evaluate.faked_scopes.append(arr)
+    cache.faked_scopes.append(arr)
     return arr
 
 
diff --git a/jedi/imports.py b/jedi/imports.py
index 03a76ca9..3226270b 100644
--- a/jedi/imports.py
+++ b/jedi/imports.py
@@ -6,6 +6,7 @@ import imp
 import sys
 import time
 
+import cache
 import builtin
 import modules
 import debug
@@ -91,7 +92,7 @@ class ImportPath(parsing.Base):
         n = parsing.Name(i.namespace.names[1:], zero, zero, self.import_stmt)
         new = parsing.Import(zero, zero, n)
         new.parent = parent
-        evaluate.faked_scopes.append(new)
+        cache.faked_scopes.append(new)
         debug.dbg('Generated a nested import: %s' % new)
         return new
 
diff --git a/jedi/modules.py b/jedi/modules.py
index 2421e913..71e300ab 100644
--- a/jedi/modules.py
+++ b/jedi/modules.py
@@ -8,6 +8,7 @@ import sys
 import os
 import time
 
+import cache
 import parsing
 import builtin
 import debug
@@ -215,7 +216,7 @@ class ModuleWithCursor(Module):
         return self._part_parser
 
 
-@evaluate.memoize_default([])
+@cache.memoize_default([])
 def sys_path_with_modifications(module):
     def execute_code(code):
         c = "import os; from os.path import *; result=%s"