diff --git a/wangle/CMakeLists.txt b/wangle/CMakeLists.txt
index 15dc8b6..ed8c79b 100644
--- a/wangle/CMakeLists.txt
+++ b/wangle/CMakeLists.txt
@@ -123,6 +123,7 @@ target_include_directories(
   PUBLIC
     $<BUILD_INTERFACE:${CMAKE_SOURCE_DIR}/..>
     $<INSTALL_INTERFACE:${INCLUDE_INSTALL_DIR}>
+  PRIVATE
     ${FIZZ_INCLUDE_DIR}
     ${FOLLY_INCLUDE_DIR}
     ${Boost_INCLUDE_DIR}