diff --git a/CMakeLists.txt b/CMakeLists.txt
index 84fb13c..ea152ef 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -113,6 +113,7 @@ if(APPLE AND NOT BOOST_ROOT)
     execute_process(COMMAND brew --prefix boost OUTPUT_VARIABLE BOOST_ROOT OUTPUT_STRIP_TRAILING_WHITESPACE)
 endif()
 if(MINGW)
+    set(MINGW_FLAG "${MINGW_FLAG} -DWIN32_LEAN_AND_MEAN")
     set(Boost_THREADAPI win32)
 endif()
 
@@ -275,8 +276,8 @@ endif()
 add_c_flag_if_supported(-fPIC C_SECURITY_FLAGS)
 add_cxx_flag_if_supported(-fPIC CXX_SECURITY_FLAGS)
 
-set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -std=c11 ${C_SECURITY_FLAGS}")
-set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${CXX_SECURITY_FLAGS}")
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${MINGW_FLAG} -std=c11 ${C_SECURITY_FLAGS}")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${MINGW_FLAG} ${CXX_SECURITY_FLAGS}")
 set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${LD_SECURITY_FLAGS} ${STATIC_FLAGS}")
 
 add_subdirectory(src)