diff --git a/termite.cc b/termite.cc
index c7af02e..bf4414e 100644
--- a/termite.cc
+++ b/termite.cc
@@ -1,6 +1,7 @@
 #define _POSIX_C_SOURCE 200809L
 
 #include <algorithm>
+#include <cstdlib>
 #include <cstring>
 #include <limits>