diff --git a/lib/api/sessions/http.cpp b/lib/api/sessions/http.cpp
index 65b52a772..e55372d3a 100644
--- a/lib/api/sessions/http.cpp
+++ b/lib/api/sessions/http.cpp
@@ -147,9 +147,11 @@ int api_http_protocol_cb(struct lws *wsi, enum lws_callback_reasons reason, void
 	void *user_ctx = lws_context_user(ctx);
 
 	Web *w = static_cast<Web *>(user_ctx);
+	Http *s = static_cast<Http *>(user);
 	Api *a = w->getApi();
 
-	Http *s = static_cast<Http *>(user);
+	if (a == nullptr)
+		return -1;
 
 	switch (reason) {
 		case LWS_CALLBACK_HTTP_BIND_PROTOCOL:
diff --git a/lib/api/sessions/websocket.cpp b/lib/api/sessions/websocket.cpp
index 86ca8a2b4..79df5bdb7 100644
--- a/lib/api/sessions/websocket.cpp
+++ b/lib/api/sessions/websocket.cpp
@@ -104,10 +104,12 @@ int api_ws_protocol_cb(lws *wsi, enum lws_callback_reasons reason, void *user, v
 	lws_context *ctx = lws_get_context(wsi);
 	void *user_ctx = lws_context_user(ctx);
 
-	Web *w = static_cast<Web*>(user_ctx);
+	Web *w = static_cast<Web *>(user_ctx);
+	WebSocket *s = static_cast<WebSocket *>(user);
 	Api *a = w->getApi();
 
-	WebSocket *s = static_cast<WebSocket *>(user);
+	if (a == nullptr)
+		return -1;
 
 	switch (reason) {
 		case LWS_CALLBACK_ESTABLISHED:
diff --git a/src/villas-pipe.cpp b/src/villas-pipe.cpp
index 0d8ebfa0e..b47668861 100644
--- a/src/villas-pipe.cpp
+++ b/src/villas-pipe.cpp
@@ -378,10 +378,7 @@ check:		if (optarg == endptr)
 	/* Only start web subsystem if villas-pipe is used with a websocket node */
 	if (node_type(node)->start == websocket_start) {
 		Web *w = sn.getWeb();
-		Api *a = sn.getApi();
-
 		w->start();
-		a->start();
 	}
 #endif /* WITH_NODE_WEBSOCKET */