diff --git a/src/aria2.h b/src/aria2.h
index 2c30174f6..16b753ccf 100644
--- a/src/aria2.h
+++ b/src/aria2.h
@@ -13,6 +13,7 @@
 
 #include <memory>
 #include <curl/curl.h>
+#include <pthread.h>
 
 namespace kiwix {