diff --git a/sd.c b/sd.c
index f28004a..5ea3298 100644
--- a/sd.c
+++ b/sd.c
@@ -1,6 +1,7 @@
+#include <assert.h>
+#include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
-#include <stdbool.h>
 #include <string.h>
 #include <time.h>
 #include <unistd.h>
@@ -56,8 +57,8 @@ int main(int argc, char* argv[]) {
 	}
 
 	/* Disable input buffering */
-	system("stty -F /dev/tty cbreak min 1");
-	system("stty -F /dev/tty -echo");
+	assert(system("stty -F /dev/tty cbreak min 1") == 0);
+	assert(system("stty -F /dev/tty -echo") == 0);
 
 	while (true) {
 		int x = (long long)rand() * rand() % seg[1];
@@ -100,6 +101,6 @@ int main(int argc, char* argv[]) {
 	}
 
 	/* Cleanup */
-	system("stty -F /dev/tty echo");
 	sqlite3_close(db);
+	assert(system("stty -F /dev/tty echo") == 0);
 }