diff --git a/include/util/static_assert.hpp b/include/util/static_assert.hpp
index ea6bc3814..28e922fd3 100644
--- a/include/util/static_assert.hpp
+++ b/include/util/static_assert.hpp
@@ -15,7 +15,7 @@ template <typename It, typename Value> inline void static_assert_iter_value()
 template <typename It, typename Category> inline void static_assert_iter_category()
 {
     using IterCategoryType = typename std::iterator_traits<It>::iterator_category;
-    static_assert(std::is_base_of<Category, IterCategoryType>::value, "");
+    static_assert(std::is_base_of_v<Category, IterCategoryType>, "");
 }
 
 } // namespace osrm::util
diff --git a/third_party/variant/include/mapbox/variant.hpp b/third_party/variant/include/mapbox/variant.hpp
index 91ec1dacb..396b4a9eb 100644
--- a/third_party/variant/include/mapbox/variant.hpp
+++ b/third_party/variant/include/mapbox/variant.hpp
@@ -163,7 +163,11 @@ struct enable_if_type
 template <typename F, typename V, typename Enable = void>
 struct result_of_unary_visit
 {
+#if __cplusplus >= 201703L
     using type = std::invoke_result_t<F, V&>;
+#else
+    using type = std::result_of_t<F(V&)>;
+#endif
 };
 
 template <typename F, typename V>
@@ -175,7 +179,11 @@ struct result_of_unary_visit<F, V, typename enable_if_type<typename F::result_ty
 template <typename F, typename V, typename Enable = void>
 struct result_of_binary_visit
 {
+#if __cplusplus >= 201703L
     using type = std::invoke_result_t<F, V&, V&>;
+#else
+    using type = std::result_of_t<F(V&, V&)>;
+#endif
 };
 
 template <typename F, typename V>