diff --git a/src/lib/swim/swim_transport.h b/src/lib/swim/swim_transport.h
index c4e48cdebd2895d5568e4f2280ae1f07786c47f2..31fd9af592b75ec85b97ce826df354adc3754465 100644
--- a/src/lib/swim/swim_transport.h
+++ b/src/lib/swim/swim_transport.h
@@ -32,6 +32,7 @@
  */
 #include <netinet/in.h>
 #include <arpa/inet.h>
+#include <unistd.h>
 
 struct ifaddrs;