--- a/src/civetweb/src/civetweb.c	2017-11-02 10:58:06.000000000 -0700
+++ b/src/civetweb/src/civetweb.c	2019-04-11 17:23:30.736346783 -0700
@@ -851,6 +851,7 @@
 #include <openssl/crypto.h>
 #include <openssl/x509.h>
 #include <openssl/pem.h>
+#include <openssl/engine.h>
 #else
 /* SSL loaded dynamically from DLL.
  * I put the prototypes here to be independent from OpenSSL source
