diff --git a/nhrpd/debug.h b/nhrpd/debug.h
new file mode 100644
index 0000000..b1f49aa
--- /dev/null
+++ b/nhrpd/debug.h
@@ -0,0 +1,42 @@
+#include "log.h"
+
+#if defined(__GNUC__) && (__GNUC__ >= 3)
+#define likely(_x) __builtin_expect(!!(_x), 1)
+#define unlikely(_x) __builtin_expect(!!(_x), 0)
+#else
+#define likely(_x) !!(_x)
+#define unlikely(_x) !!(_x)
+#endif
+
+#define NHRP_DEBUG_COMMON	(1 << 0)
+#define NHRP_DEBUG_KERNEL	(1 << 1)
+#define NHRP_DEBUG_IF		(1 << 2)
+#define NHRP_DEBUG_ROUTE	(1 << 3)
+#define NHRP_DEBUG_VICI		(1 << 4)
+#define NHRP_DEBUG_EVENT	(1 << 5)
+#define NHRP_DEBUG_ALL		(0xFFFF)
+
+extern unsigned int debug_flags;
+
+#if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L
+
+#define debugf(level, ...) \
+	do {						\
+		if (unlikely(debug_flags & level))	\
+			zlog_debug(__VA_ARGS__);	\
+	} while(0)
+
+#elif defined __GNUC__
+
+#define debugf(level, _args...)				\
+	do {						\
+		if (unlikely(debug_flags & level))	\
+			zlog_debug(_args);		\
+	} while(0)
+
+#else
+
+static inline void debugf(int level, const char *format, ...) { }
+
+#endif
+