diff --git a/src/qsplib/CMakeLists.txt b/src/qsplib/CMakeLists.txt
index e7445cb..5e93a24 100644
--- a/src/qsplib/CMakeLists.txt
+++ b/src/qsplib/CMakeLists.txt
@@ -61,7 +61,7 @@ set_target_properties(qsp-engine-debug PROPERTIES LINK_FLAGS "-Wno-parentheses \
     -Wdeprecated-non-prototype \
     -fsanitize=address \
     -gsource-map \
-    -O3 \
+    -O1 \
     -sASSERTIONS \
     -s EXPORT_ES6=1 \
     -s WASM=1 \