diff --git a/traits-stubs/traits-stubs/api.pyi b/traits-stubs/traits-stubs/api.pyi
index 57b1f1083..833f8bd4b 100644
--- a/traits-stubs/traits-stubs/api.pyi
+++ b/traits-stubs/traits-stubs/api.pyi
@@ -8,7 +8,16 @@
 #
 # Thanks for using Enthought open source!
 
-from .trait_type import TraitType as TraitType
+from .constants import (
+    ComparisonMode as ComparisonMode,
+    DefaultValue as DefaultValue,
+    TraitKind as TraitKind,
+    ValidateTrait as ValidateTrait,
+    NO_COMPARE as NO_COMPARE,
+    OBJECT_IDENTITY_COMPARE as OBJECT_IDENTITY_COMPARE,
+    RICH_COMPARE as RICH_COMPARE,
+)
+
 from .traits import (
     Color as Color,
     Default as Default,
@@ -18,9 +27,30 @@ from .traits import (
     Trait as Trait
 )
 
+from .ctrait import CTrait as CTrait
+
 from .has_traits import (
+    ABCHasStrictTraits as ABCHasStrictTraits,
+    ABCHasTraits as ABCHasTraits,
+    ABCMetaHasTraits as ABCMetaHasTraits,
+    AbstractViewElement as AbstractViewElement,
     HasTraits as HasTraits,
+    HasStrictTraits as HasStrictTraits,
+    HasPrivateTraits as HasPrivateTraits,
+    HasRequiredTraits as HasRequiredTraits,
+    Interface as Interface,
+    SingletonHasTraits as SingletonHasTraits,
+    SingletonHasStrictTraits as SingletonHasStrictTraits,
+    SingletonHasPrivateTraits as SingletonHasPrivateTraits,
+    MetaHasTraits as MetaHasTraits,
+    Vetoable as Vetoable,
+    VetoableEvent as VetoableEvent,
     observe as observe,
+    on_trait_change as on_trait_change,
+    cached_property as cached_property,
+    property_depends_on as property_depends_on,
+    provides as provides,
+    isinterface as isinterface,
 )
 
 from .trait_types import (
@@ -146,6 +176,9 @@ from .trait_types import (
     ValidatedTuple as ValidatedTuple
 )
 
+from .base_trait_handler import BaseTraitHandler as BaseTraitHandler
+from .trait_handler import TraitHandler as TraitHandler
+from .trait_type import TraitType as TraitType
 from .trait_handlers import (
     TraitCoerceType as TraitCoerceType,
     TraitCastType as TraitCastType,
diff --git a/traits-stubs/traits-stubs/base_trait_hander.pyi b/traits-stubs/traits-stubs/base_trait_hander.pyi
deleted file mode 100644
index 3e9b1671f..000000000
--- a/traits-stubs/traits-stubs/base_trait_hander.pyi
+++ /dev/null
@@ -1,13 +0,0 @@
-# (C) Copyright 2005-2020 Enthought, Inc., Austin, TX
-# All rights reserved.
-#
-# This software is provided without warranty under the terms of the BSD
-# license included in LICENSE.txt and may be redistributed only under
-# the conditions described in the aforementioned license. The license
-# is also available online at http://www.enthought.com/licenses/BSD.txt
-#
-# Thanks for using Enthought open source!
-
-
-class BaseTraitHandler(object):
-    ...
diff --git a/traits-stubs/traits-stubs/trait_handler.pyi b/traits-stubs/traits-stubs/trait_handler.pyi
index 02b463ccc..d0f24c8b3 100644
--- a/traits-stubs/traits-stubs/trait_handler.pyi
+++ b/traits-stubs/traits-stubs/trait_handler.pyi
@@ -8,8 +8,8 @@
 #
 # Thanks for using Enthought open source!
 
-from .base_trait_hander import BaseTraitHandler
+from .base_trait_handler import BaseTraitHandler
 
 
 class TraitHandler(BaseTraitHandler):
-    ...
\ No newline at end of file
+    ...
diff --git a/traits-stubs/traits_stubs_tests/examples/HasStrictTraits.py b/traits-stubs/traits_stubs_tests/examples/HasStrictTraits.py
new file mode 100644
index 000000000..ccb19f878
--- /dev/null
+++ b/traits-stubs/traits_stubs_tests/examples/HasStrictTraits.py
@@ -0,0 +1,17 @@
+from traits.api import Event, HasStrictTraits, observe
+
+
+class Person(HasStrictTraits):
+    conductor = Event()
+
+    @observe("conductor")
+    def talk(self, event):
+        pass
+
+
+def sing(event):
+    pass
+
+
+person = Person()
+person.observe(sing, "conductor")
diff --git a/traits-stubs/traits_stubs_tests/examples/Interface.py b/traits-stubs/traits_stubs_tests/examples/Interface.py
new file mode 100644
index 000000000..660fb6400
--- /dev/null
+++ b/traits-stubs/traits_stubs_tests/examples/Interface.py
@@ -0,0 +1,15 @@
+from traits.api import Float, HasTraits, Interface, provides, Str, Tuple
+
+
+class IHasName(Interface):
+    name = Str()
+
+
+@provides(IHasName)
+class NamedColor(HasTraits):
+    name = Str()
+
+    rgb = Tuple(Float, Float, Float)
+
+
+named_color = NamedColor(name="green", rgb=(0.0, 1.0, 0.0))