diff --git a/CMakeLists.txt b/CMakeLists.txt
index 75df44f..3cf4f1a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -2,6 +2,7 @@ cmake_minimum_required(VERSION 3.1.0 FATAL_ERROR)
 project (lgogdownloader LANGUAGES CXX VERSION 2.26)
 
 set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}/cmake/")
+set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -DDEBUG=1")
 
 find_package(Boost
   REQUIRED