diff --git a/rust/ql/test/library-tests/elements/builtintypes/BuiltinTypes.expected b/rust/ql/test/library-tests/elements/builtintypes/BuiltinTypes.expected
index cfab22cd61c3..e08eb561b58b 100644
--- a/rust/ql/test/library-tests/elements/builtintypes/BuiltinTypes.expected
+++ b/rust/ql/test/library-tests/elements/builtintypes/BuiltinTypes.expected
@@ -1,6 +1,8 @@
 | struct Array |  |
 | struct Ptr |  |
+| struct PtrMut |  |
 | struct Ref |  |
+| struct RefMut |  |
 | struct Slice |  |
 | struct Tuple0 |  |
 | struct Tuple1 |  |
diff --git a/rust/tools/builtins/types.rs b/rust/tools/builtins/types.rs
index 0c6025b4d37d..fc0be525ab44 100644
--- a/rust/tools/builtins/types.rs
+++ b/rust/tools/builtins/types.rs
@@ -26,8 +26,10 @@ pub struct f64;
 
 struct Slice<TSlice>;
 struct Array<TArray, const N: usize>;
-struct Ref<TRef>; // todo: add mut variant
-struct Ptr<TPtr>; // todo: add mut variant
+struct Ref<TRef>;
+struct RefMut<TRefMut>;
+struct Ptr<TPtr>;
+struct PtrMut<TPtrMut>;
 
 // tuples
 struct Tuple0;