diff --git a/lib/ibus-menu.vala b/lib/ibus-menu.vala
index a240f00..beefe9c 100644
--- a/lib/ibus-menu.vala
+++ b/lib/ibus-menu.vala
@@ -279,7 +279,7 @@ public class Indicator.Keyboard.IBusMenu : MenuModel {
 
 	/* Forward all menu model calls to our internal menu. */
 
-	public override Variant get_item_attribute_value (int item_index, string attribute, VariantType? expected_type) {
+	public override Variant? get_item_attribute_value (int item_index, string attribute, VariantType? expected_type) {
 		return menu.get_item_attribute_value (item_index, attribute, expected_type);
 	}
 
@@ -287,7 +287,7 @@ public class Indicator.Keyboard.IBusMenu : MenuModel {
 		menu.get_item_attributes (item_index, out attributes);
 	}
 
-	public override MenuModel get_item_link (int item_index, string link) {
+	public override MenuModel? get_item_link (int item_index, string link) {
 		return menu.get_item_link (item_index, link);
 	}
 
diff --git a/lib/indicator-menu.vala b/lib/indicator-menu.vala
index 80eacf3..659009a 100644
--- a/lib/indicator-menu.vala
+++ b/lib/indicator-menu.vala
@@ -151,11 +151,11 @@ public class Indicator.Keyboard.IndicatorMenu : MenuModel {
 		indicator_menu.get_item_links (item_index, out links);
 	}
 
-	public override Variant get_item_attribute_value (int item_index, string attribute, VariantType? expected_type) {
+	public override Variant? get_item_attribute_value (int item_index, string attribute, VariantType? expected_type) {
 		return indicator_menu.get_item_attribute_value (item_index, attribute, expected_type);
 	}
 
-	public override MenuModel get_item_link (int item_index, string link) {
+	public override MenuModel? get_item_link (int item_index, string link) {
 		return indicator_menu.get_item_link (item_index, link);
 	}
 
diff --git a/lib/main.vala b/lib/main.vala
index 8b077ff..eb2f24e 100644
--- a/lib/main.vala
+++ b/lib/main.vala
@@ -839,7 +839,7 @@ public class Indicator.Keyboard.Service : Object {
 		string? name = null;
 
 		var sources = get_sources ();
-		var active = get_active_action ().get_state ().get_uint32 ();
+		var active = ((!) get_active_action ().get_state ()).get_uint32 ();
 
 		if (active < sources.length) {
 			icon = sources[active].icon;
@@ -983,7 +983,7 @@ public class Indicator.Keyboard.Service : Object {
 
 			if (xkb_length > 1) {
 				var active_action = get_active_action ();
-				var active = active_action.get_state ().get_uint32 ();
+				var active = ((!) active_action.get_state ()).get_uint32 ();
 				var offset = -((!) parameter).get_int32 () % xkb_length;
 
 				/* Make offset positive modulo xkb_length. */
diff --git a/tests/services/ca.desrt.dconf.service b/tests/services/ca.desrt.dconf.service
index 7ce3879..1c2c24d 100644
--- a/tests/services/ca.desrt.dconf.service
+++ b/tests/services/ca.desrt.dconf.service
@@ -1,3 +1,3 @@
 [D-BUS Service]
 Name=ca.desrt.dconf
-Exec=/usr/lib/dconf/dconf-service
+Exec=/usr/libexec/dconf-service