diff --git a/libs/ui/include/psemek/ui/element.hpp b/libs/ui/include/psemek/ui/element.hpp
index d302a5be..176d5413 100644
--- a/libs/ui/include/psemek/ui/element.hpp
+++ b/libs/ui/include/psemek/ui/element.hpp
@@ -61,7 +61,7 @@ namespace psemek::ui
 
 		virtual ~element() {}
 
-		virtual void post(util::function<void()> f);
+		virtual void post(util::function<void()> f) const;
 		virtual void post_reshape();
 
 	protected:
diff --git a/libs/ui/source/element.cpp b/libs/ui/source/element.cpp
index 882cec9a..0612f746 100644
--- a/libs/ui/source/element.cpp
+++ b/libs/ui/source/element.cpp
@@ -79,7 +79,7 @@ namespace psemek::ui
 		return merged_style_;
 	}
 
-	void element::post(util::function<void()> f)
+	void element::post(util::function<void()> f) const
 	{
 		auto l = loop();
 		if (l)