diff --git a/core/common.hpp b/core/common.hpp
index 38cf178..cc999d8 100644
--- a/core/common.hpp
+++ b/core/common.hpp
@@ -114,9 +114,9 @@
 namespace scheduler = ndn::scheduler;
 namespace signal = ndn::signal;
 namespace time = ndn::time;
-using namespace ndn::time_literals;
 
-using ndn::operator""_block;
+using namespace ndn::block_literals;
+using namespace ndn::time_literals;
 
 } // namespace nfd