diff --git a/Atk.overrides b/Atk.overrides
--- a/Atk.overrides
+++ b/Atk.overrides
@@ -2,3 +2,68 @@
 
 # Not marked properly as a GType struct (which we hide)
 ignore _RegistryClass
+
+# Generated from atk 2.20.0 with xsltproc Nullable.xslt Atk-1.0.gir
+set-attr Atk/Action/get_description/@return-value nullable 1
+set-attr Atk/Action/get_keybinding/@return-value nullable 1
+set-attr Atk/Action/get_localized_name/@return-value nullable 1
+set-attr Atk/Action/get_name/@return-value nullable 1
+set-attr Atk/Action/get_description/@return-value nullable 1
+set-attr Atk/Action/get_keybinding/@return-value nullable 1
+set-attr Atk/Action/get_localized_name/@return-value nullable 1
+set-attr Atk/Action/get_name/@return-value nullable 1
+set-attr Atk/ActionIface/get_description/get_description/@return-value nullable 1
+set-attr Atk/ActionIface/get_name/get_name/@return-value nullable 1
+set-attr Atk/ActionIface/get_keybinding/get_keybinding/@return-value nullable 1
+set-attr Atk/ActionIface/get_localized_name/get_localized_name/@return-value nullable 1
+set-attr Atk/Component/ref_accessible_at_point/@return-value nullable 1
+set-attr Atk/Component/ref_accessible_at_point/@return-value nullable 1
+set-attr Atk/ComponentIface/ref_accessible_at_point/ref_accessible_at_point/@return-value nullable 1
+set-attr Atk/Document/get_document/@return-value nullable 1
+set-attr Atk/Document/get_attribute_value/@return-value nullable 1
+set-attr Atk/Document/get_document/@return-value nullable 1
+set-attr Atk/DocumentIface/get_document/get_document/@return-value nullable 1
+set-attr Atk/Function/@parameters/user_data nullable 1
+set-attr Atk/Image/get_image_locale/@return-value nullable 1
+set-attr Atk/Image/get_image_locale/@return-value nullable 1
+set-attr Atk/ImageIface/get_image_locale/get_image_locale/@return-value nullable 1
+set-attr Atk/KeySnoopFunc/@parameters/user_data nullable 1
+set-attr Atk/Object/active_descendant_changed/@parameters/child nullable 1
+set-attr Atk/Object/children_changed/@parameters/changed_child nullable 1
+set-attr Atk/Object/initialize/@parameters/data nullable 1
+set-attr Atk/Object/initialize/@parameters/data nullable 1
+set-attr Atk/Object/active-descendant-changed/@parameters/arg1 nullable 1
+set-attr Atk/Object/children-changed/@parameters/arg2 nullable 1
+set-attr Atk/Object/property-change/@parameters/arg1 nullable 1
+set-attr Atk/ObjectClass/initialize/initialize/@parameters/data nullable 1
+set-attr Atk/ObjectClass/children_changed/children_changed/@parameters/changed_child nullable 1
+set-attr Atk/ObjectClass/active_descendant_changed/active_descendant_changed/@parameters/child nullable 1
+set-attr Atk/Selection/ref_selection/@return-value nullable 1
+set-attr Atk/Selection/ref_selection/@return-value nullable 1
+set-attr Atk/SelectionIface/ref_selection/ref_selection/@return-value nullable 1
+set-attr Atk/StateSet/or_sets/@return-value nullable 1
+set-attr Atk/StreamableContent/get_uri/@return-value nullable 1
+set-attr Atk/StreamableContent/get_uri/@return-value nullable 1
+set-attr Atk/StreamableContentIface/get_uri/get_uri/@return-value nullable 1
+set-attr Atk/Table/get_caption/@return-value nullable 1
+set-attr Atk/Table/get_column_header/@return-value nullable 1
+set-attr Atk/Table/get_row_description/@return-value nullable 1
+set-attr Atk/Table/get_row_header/@return-value nullable 1
+set-attr Atk/Table/get_caption/@return-value nullable 1
+set-attr Atk/Table/get_column_header/@return-value nullable 1
+set-attr Atk/Table/get_row_description/@return-value nullable 1
+set-attr Atk/Table/get_row_header/@return-value nullable 1
+set-attr Atk/TableIface/get_caption/get_caption/@return-value nullable 1
+set-attr Atk/TableIface/get_column_header/get_column_header/@return-value nullable 1
+set-attr Atk/TableIface/get_row_description/get_row_description/@return-value nullable 1
+set-attr Atk/TableIface/get_row_header/get_row_header/@return-value nullable 1
+set-attr Atk/Text/get_string_at_offset/@return-value nullable 1
+set-attr Atk/Text/get_string_at_offset/@return-value nullable 1
+set-attr Atk/TextAttribute/get_value/@return-value nullable 1
+set-attr Atk/TextIface/get_string_at_offset/get_string_at_offset/@return-value nullable 1
+set-attr Atk/UtilClass/add_key_event_listener/add_key_event_listener/@parameters/data nullable 1
+set-attr Atk/Value/get_range/@return-value nullable 1
+set-attr Atk/Value/get_range/@return-value nullable 1
+set-attr Atk/ValueIface/get_range/get_range/@return-value nullable 1
+set-attr Atk/add_key_event_listener/@parameters/data nullable 1
+set-attr Atk/text_attribute_get_value/@return-value nullable 1
diff --git a/gi-atk.cabal b/gi-atk.cabal
--- a/gi-atk.cabal
+++ b/gi-atk.cabal
@@ -1,5 +1,5 @@
 name:                 gi-atk
-version:              2.0.4
+version:              2.0.5
 synopsis:             Atk bindings
 description:          Bindings for Atk, autogenerated by haskell-gi.
 homepage:             https://github.com/haskell-gi/haskell-gi
@@ -15,6 +15,7 @@
 
 custom-setup
       setup-depends: base >= 4.7 && < 5,
+                     Cabal >= 1.24,
                      haskell-gi >= 0.17.3 && < 1
 
 library