diff --git a/jedi/evaluate/context/instance.py b/jedi/evaluate/context/instance.py
index 3136b376..78ba10ea 100644
--- a/jedi/evaluate/context/instance.py
+++ b/jedi/evaluate/context/instance.py
@@ -403,16 +403,12 @@ class BoundMethod(FunctionMixin, ContextWrapper):
         return '<%s: %s>' % (self.__class__.__name__, self._wrapped_context)
 
 
-class CompiledBoundMethod(compiled.CompiledObject):
-    def __init__(self, func):
-        super(CompiledBoundMethod, self).__init__(
-            func.evaluator, func.access_handle, func.parent_context)
-
+class CompiledBoundMethod(ContextWrapper):
     def is_bound_method(self):
         return True
 
-    def get_param_names(self):
-        return list(super(CompiledBoundMethod, self).get_param_names())[1:]
+    def get_signatures(self):
+        return [sig.bind(self) for sig in self._wrapped_context.get_signatures()]
 
 
 class SelfName(TreeNameDefinition):
diff --git a/jedi/evaluate/signature.py b/jedi/evaluate/signature.py
index 1138617d..8206c11c 100644
--- a/jedi/evaluate/signature.py
+++ b/jedi/evaluate/signature.py
@@ -88,4 +88,5 @@ class BuiltinSignature(AbstractSignature):
         return self.context
 
     def bind(self, context):
-        raise NotImplementedError('pls implement, need test case, %s' % context)
+        assert not self.is_bound
+        return BuiltinSignature(context, self._return_string, is_bound=True)