diff --git a/.github/matrix.py b/.github/matrix.py
index b5eec8b5d..2d1dfe241 100755
--- a/.github/matrix.py
+++ b/.github/matrix.py
@@ -207,6 +207,7 @@ def main(ref_name):
                         'OPT_CFLAGS="-O1"',
                         "USE_ZLIB=1",
                         "USE_OT=1",
+                        "DEBUG=-DDEBUG_STRICT=2",
                         "OT_INC=${HOME}/opt-ot/include",
                         "OT_LIB=${HOME}/opt-ot/lib",
                         "OT_RUNPATH=1",