diff --git a/c_src/towerops_nif.c b/c_src/towerops_nif.c
index 65627bfe..d6533e34 100644
--- a/c_src/towerops_nif.c
+++ b/c_src/towerops_nif.c
@@ -1,6 +1,10 @@
 // Pure C NIF for net-snmp MIB resolution
 // Directly links to libnetsnmp without Rust layer
 
+// Enable BSD types (u_char, u_short, etc.) on newer glibc
+#define _DEFAULT_SOURCE
+#define _BSD_SOURCE
+
 #include <erl_nif.h>
 #include <sys/types.h>
 #include <net-snmp/net-snmp-config.h>