diff --git a/lib/CMakeLists.txt b/lib/CMakeLists.txt
index 0846d06..290679f 100644
--- a/lib/CMakeLists.txt
+++ b/lib/CMakeLists.txt
@@ -38,7 +38,7 @@ if(WIN32)
 endif()
 
 # Public shared library
-add_library(nghttp2 SHARED ${NGHTTP2_SOURCES} ${NGHTTP2_RES})
+add_library(nghttp2 ${NGHTTP2_SOURCES} ${NGHTTP2_RES})
 set_target_properties(nghttp2 PROPERTIES
   COMPILE_FLAGS "${WARNCFLAGS}"
   VERSION ${LT_VERSION} SOVERSION ${LT_SOVERSION}
@@ -48,6 +48,9 @@ target_include_directories(nghttp2 INTERFACE
     "${CMAKE_CURRENT_BINARY_DIR}/includes"
     "${CMAKE_CURRENT_SOURCE_DIR}/includes"
     )
+if(NOT BUILD_SHARED_LIBS)
+  target_compile_definitions(nghttp2 PUBLIC "-DNGHTTP2_STATICLIB")
+endif()
 
 if(HAVE_CUNIT)
   # Static library (for unittests because of symbol visibility)