diff --git a/src/koinos/mempool/mempool.hpp b/src/koinos/mempool/mempool.hpp
index c1e0e5d..16e82be 100644
--- a/src/koinos/mempool/mempool.hpp
+++ b/src/koinos/mempool/mempool.hpp
@@ -39,7 +39,7 @@ class mempool final
 {
 private:
   std::unique_ptr< detail::mempool_impl > _my;
-  mutable std::mutex                      _mutex;
+  mutable std::mutex _mutex;
 
 public:
   mempool( state_db::fork_resolution_algorithm algo = state_db::fork_resolution_algorithm::fifo );