diff --git a/lib/meson.build b/lib/meson.build
index fa28025..2be7040 100644
--- a/lib/meson.build
+++ b/lib/meson.build
@@ -72,6 +72,7 @@ pkg.generate(
 )
 
 libmks_gir = gnome.generate_gir(libmks,
+              sources: libmks_sources + libmks_headers,
             nsversion: api_version,
             namespace: 'Mks',
         symbol_prefix: 'mks',