diff --git a/desktop/src-tauri/src/app_state.rs b/desktop/src-tauri/src/app_state.rs
index 4f595c348..d80f7c892 100644
--- a/desktop/src-tauri/src/app_state.rs
+++ b/desktop/src-tauri/src/app_state.rs
@@ -84,6 +84,12 @@ pub fn build_app_state() -> AppState {
     AppState {
         keys: Mutex::new(keys),
         http_client: reqwest::Client::builder()
+            // Keep URL authority/Host headers intact for relay tenant binding,
+            // but avoid macOS/IPv6 localhost flakiness for local dev services.
+            // reqwest uses the URL port over this port-0 DNS override, so
+            // http://localhost:3000 still sends Host: localhost:3000 while
+            // connecting to 127.0.0.1:3000 instead of ::1.
+            .resolve("localhost", std::net::SocketAddr::from(([127, 0, 0, 1], 0)))
             .pool_idle_timeout(std::time::Duration::from_secs(10))
             .pool_max_idle_per_host(1)
             .build()