diff --git a/src/main.rs b/src/main.rs
index 9a84829..5538441 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -10,7 +10,7 @@ use controller::*;
 use view::view::*;
 
 fn main() {
-    let app = adw::Application::builder()
+    let app: adw::Application = adw::Application::builder()
         .application_id("com.github.gtk-rs.examples.basic")
         .build();