diff --git a/include/tl/expected.hpp b/include/tl/expected.hpp
index f154190..4bc30ad 100644
--- a/include/tl/expected.hpp
+++ b/include/tl/expected.hpp
@@ -26,9 +26,11 @@
 #include <utility>
 
 #if !defined(TL_ASSERT)
+#if (__cplusplus > 201103L) //can't have assert in constexpr in C++11
 #include <cassert>
 #define TL_ASSERT assert
 #endif
+#endif
 
 #if defined(__EXCEPTIONS) || defined(_CPPUNWIND)
 #define TL_EXPECTED_EXCEPTIONS_ENABLED