diff --git a/unix/Makefile b/unix/Makefile
index fd1c1999dd..2e0cbfd35a 100644
--- a/unix/Makefile
+++ b/unix/Makefile
@@ -94,7 +94,7 @@ CFLAGS_MOD += -DMICROPY_PY_SOCKET=1
 SRC_MOD += modsocket.c
 endif
 ifeq ($(MICROPY_PY_THREAD),1)
-CFLAGS_MOD += -DMICROPY_PY_THREAD=1
+CFLAGS_MOD += -DMICROPY_PY_THREAD=1 -DMICROPY_PY_THREAD_GIL=0
 LDFLAGS_MOD += -lpthread
 endif