diff --git a/services/api/src/main.rs b/services/api/src/main.rs
index 0e9ea61..bcf5656 100644
--- a/services/api/src/main.rs
+++ b/services/api/src/main.rs
@@ -11,7 +11,7 @@ mod session;
 
 use std::sync::Arc;
 
-use axum::serve::ListenerExt;
+use axum::serve::{Listener, ListenerExt};
 
 use crate::config::Config;
 use crate::routes::AppState;
@@ -103,7 +103,15 @@ async fn main() {
                 tracing::debug!("set_nodelay failed: {e}");
             }
         });
-    tracing::info!("listening on {}", config.bind_addr);
+    // The bound address, not the configured one: BIND_ADDR=127.0.0.1:0 asks
+    // the OS for whichever port is free, which is what scripts/dev-instance.sh
+    // relies on this line to report - logging config.bind_addr back would
+    // always print :0 and never say which port actually opened.
+    let bound = listener
+        .local_addr()
+        .map(|a| a.to_string())
+        .unwrap_or_else(|_| config.bind_addr.to_string());
+    tracing::info!("listening on {bound}");
 
     axum::serve(listener, routes::app(state))
         .with_graceful_shutdown(shutdown_signal())