diff -ur nginx-1.15.0-wolfssl/src/event/ngx_event_openssl.c nginx-1.15.0-wolfssl-debug/src/event/ngx_event_openssl.c
--- nginx-1.15.0-wolfssl/src/event/ngx_event_openssl.c	2018-06-14 15:44:59.055897015 +1000
+++ nginx-1.15.0-wolfssl-debug/src/event/ngx_event_openssl.c	2018-06-14 15:45:28.216021713 +1000
@@ -144,6 +144,11 @@
 
 #endif
 
+#ifdef WOLFSSL_NGINX
+    /* Turn on internal wolfssl debugging to stdout */
+    wolfSSL_Debugging_ON();
+#endif
+
 #if OPENSSL_VERSION_NUMBER >= 0x0090800fL
 #ifndef SSL_OP_NO_COMPRESSION
     {
Only in nginx-1.15.0-wolfssl-debug/src/event: ngx_event_openssl.c.orig