diff --git a/examples/natmod/btree/btree_c.c b/examples/natmod/btree/btree_c.c
index c8c5cef471..f3e4790ed2 100644
--- a/examples/natmod/btree/btree_c.c
+++ b/examples/natmod/btree/btree_c.c
@@ -1,4 +1,3 @@
-#define MICROPY_ENABLE_DYNRUNTIME (1)
 #define MICROPY_PY_BTREE (1)
 
 #include "py/dynruntime.h"
diff --git a/examples/natmod/framebuf/framebuf.c b/examples/natmod/framebuf/framebuf.c
index 8f322c204a..8d488cffd6 100644
--- a/examples/natmod/framebuf/framebuf.c
+++ b/examples/natmod/framebuf/framebuf.c
@@ -1,4 +1,3 @@
-#define MICROPY_ENABLE_DYNRUNTIME (1)
 #define MICROPY_PY_FRAMEBUF (1)
 
 #include "py/dynruntime.h"
diff --git a/examples/natmod/uheapq/uheapq.c b/examples/natmod/uheapq/uheapq.c
index df880bd382..9da6bb4ada 100644
--- a/examples/natmod/uheapq/uheapq.c
+++ b/examples/natmod/uheapq/uheapq.c
@@ -1,4 +1,3 @@
-#define MICROPY_ENABLE_DYNRUNTIME (1)
 #define MICROPY_PY_UHEAPQ (1)
 
 #include "py/dynruntime.h"
diff --git a/examples/natmod/urandom/urandom.c b/examples/natmod/urandom/urandom.c
index 732e439eea..e1fed6a554 100644
--- a/examples/natmod/urandom/urandom.c
+++ b/examples/natmod/urandom/urandom.c
@@ -1,4 +1,3 @@
-#define MICROPY_ENABLE_DYNRUNTIME (1)
 #define MICROPY_PY_URANDOM (1)
 #define MICROPY_PY_URANDOM_EXTRA_FUNCS (1)
 
diff --git a/examples/natmod/ure/ure.c b/examples/natmod/ure/ure.c
index 6c9e9e307e..ca1383583a 100644
--- a/examples/natmod/ure/ure.c
+++ b/examples/natmod/ure/ure.c
@@ -1,4 +1,3 @@
-#define MICROPY_ENABLE_DYNRUNTIME (1)
 #define MICROPY_STACK_CHECK (1)
 #define MICROPY_PY_URE (1)
 #define MICROPY_PY_URE_MATCH_GROUPS (1)
diff --git a/examples/natmod/uzlib/uzlib.c b/examples/natmod/uzlib/uzlib.c
index 4873171e5e..99b3691761 100644
--- a/examples/natmod/uzlib/uzlib.c
+++ b/examples/natmod/uzlib/uzlib.c
@@ -1,4 +1,3 @@
-#define MICROPY_ENABLE_DYNRUNTIME (1)
 #define MICROPY_PY_UZLIB (1)
 
 #include "py/dynruntime.h"
diff --git a/py/dynruntime.h b/py/dynruntime.h
index 494ad772df..9f2803c535 100644
--- a/py/dynruntime.h
+++ b/py/dynruntime.h
@@ -33,6 +33,10 @@
 #include "py/objstr.h"
 #include "py/objtype.h"
 
+#if !MICROPY_ENABLE_DYNRUNTIME
+#error "dynruntime.h included in non-dynamic-module build."
+#endif
+
 #undef MP_ROM_QSTR
 #undef MP_OBJ_QSTR_VALUE
 #undef MP_OBJ_NEW_QSTR
diff --git a/py/dynruntime.mk b/py/dynruntime.mk
index 8b65745afd..cb5ab845eb 100644
--- a/py/dynruntime.mk
+++ b/py/dynruntime.mk
@@ -27,6 +27,7 @@ CFLAGS += -std=c99
 CFLAGS += -Os
 CFLAGS += -Wall -Werror -DNDEBUG
 CFLAGS += -DNO_QSTR
+CFLAGS += -DMICROPY_ENABLE_DYNRUNTIME
 CFLAGS += -DMP_CONFIGFILE='<$(CONFIG_H)>'
 CFLAGS += -fpic -fno-common
 CFLAGS += -U _FORTIFY_SOURCE # prevent use of __*_chk libc functions