diff --git a/source/mijin/async/future.hpp b/source/mijin/async/future.hpp
index 0ccbc19..5fe417c 100644
--- a/source/mijin/async/future.hpp
+++ b/source/mijin/async/future.hpp
@@ -34,21 +34,21 @@ namespace impl
 template<typename TValue>
 struct FutureStorage
 {
-    std::optional<TValue> value;
+    Optional<TValue> value;
 
     void setValue(TValue value_) noexcept { value = std::move(value_); }
-    [[nodiscard]] TValue& getValue() noexcept { return value.value(); }
+    [[nodiscard]] TValue& getValue() noexcept { return value.get(); }
 
 };
 
-template<typename TValue>
-struct FutureStorage<TValue&>
-{
-    std::optional<TValue*> value;
-
-    void setValue(TValue& value_) noexcept { value = &value_; }
-    [[nodiscard]] TValue& getValue() const noexcept { return *value.value(); }
-};
+// template<typename TValue>
+// struct FutureStorage<TValue&>
+// {
+//     Optional<TValue*> value;
+//
+//     void setValue(TValue& value_) noexcept { value = &value_; }
+//     [[nodiscard]] TValue& getValue() const noexcept { return *value.get(); }
+// };
 
 template<>
 struct FutureStorage<void>