diff --git a/include/villas/utils.h b/include/villas/utils.h
index 62c6a9e7a..aa76bc048 100644
--- a/include/villas/utils.h
+++ b/include/villas/utils.h
@@ -176,6 +176,7 @@ char * cpulist_create(char *str, size_t len, cpu_set_t *set);
 json_t * config_to_json(config_setting_t *cfg);
 
 #endif
+int json_to_config(json_t *json, config_setting_t *parent);
 
 /** Allocate and initialize memory. */
 void * alloc(size_t bytes);
diff --git a/plugins/hooks/example_hook.c b/plugins/hooks/example_hook.c
index 1bd247fd2..aa7089102 100644
--- a/plugins/hooks/example_hook.c
+++ b/plugins/hooks/example_hook.c
@@ -14,10 +14,10 @@ struct hook;
 struct path;
 struct sample;
 
-static int hook_example(struct hook *h, int when, struct hook_info *j)
+static int example_start(struct hook *h)
 {
 	info("Hello world from example hook!");
-	
+
 	return 0;
 }
 
@@ -27,8 +27,7 @@ static struct plugin p = {
 	.type		= PLUGIN_TYPE_HOOK,
 	.hook		= {
 		.priority = 99,
-		.cb	= hook_example,
-		.when	= HOOK_PATH_START
+		.start	= example_start
 	}
 };