diff --git a/third_party/datetime.cmake b/third_party/datetime.cmake
index f96aa06c..d59808a2 100644
--- a/third_party/datetime.cmake
+++ b/third_party/datetime.cmake
@@ -3,6 +3,7 @@
 include_guard(GLOBAL)
 
 set (BUILD_TZ_LIB ON CACHE BOOL "timezone library is a dependency" FORCE)
+set (USE_SYSTEM_TZ_DB ON CACHE BOOL "use OS compiled timezone database" FORCE)
 include(FetchContent)
 FetchContent_Declare(date_src
         GIT_REPOSITORY https://github.com/HowardHinnant/date.git