diff --git a/includes/back-compat/trait-wpdo-anti-eav-aware-alias.php b/includes/back-compat/trait-wpdo-anti-eav-aware-alias.php
index 2d54ec6..c42c5ae 100644
--- a/includes/back-compat/trait-wpdo-anti-eav-aware-alias.php
+++ b/includes/back-compat/trait-wpdo-anti-eav-aware-alias.php
@@ -30,11 +30,6 @@ if ( ! trait_exists( 'WPDO_Anti_EAV_Aware', false ) && trait_exists( 'TMDO_Anti_
 	}
 }
 
-if ( ! interface_exists( 'WPDO_Entity_Adapter_Interface', false ) && interface_exists( 'TMDO_Entity_Adapter_Interface', false ) ) {
-	/**
-	 * Backward-compat alias interface. PHP allows interface inheritance, so
-	 * extending the new interface gives implementing classes the same
-	 * obligations under the old name.
-	 */
-	interface WPDO_Entity_Adapter_Interface extends TMDO_Entity_Adapter_Interface {}
-}
+// NOTE: WPDO_Entity_Adapter_Interface is declared in
+// back-compat/interface-wpdo-entity-adapter-alias.php — it used to be duplicated
+// here, which made composer's classmap ambiguous.
diff --git a/includes/class-tmdo-back-compat.php b/includes/class-tmdo-back-compat.php
index 8f5be88..e32a644 100644
--- a/includes/class-tmdo-back-compat.php
+++ b/includes/class-tmdo-back-compat.php
@@ -128,7 +128,7 @@ $tmdo_class_aliases = array(
 	'TMDO_Zone_Archive'               => 'WPDO_Zone_Archive',
 	'TMDO_Interceptor_Base'           => 'WPDO_Interceptor_Base',
 	'TMDO_Query_Interceptor_Base'     => 'WPDO_Query_Interceptor_Base',
-	'TMDO_Notifier'                   => 'WPDO_Notifier',
+	'TMDO_Abstract_Notifier'          => 'WPDO_Abstract_Notifier',
 );
 
 foreach ( $tmdo_class_aliases as $tmdo_class => $wpdo_alias ) {
@@ -172,7 +172,21 @@ if ( ! defined( 'WPDO_IS_MYSQL' ) ) {
 }
 
 // ── Hook dual-fire bridge ─────────────────────────────────────────────────
-// Phase 1 過渡期：tmdo_* 與 wpdo_* hook 雙向轉發，讓既有 listener 仍能接收事件。
+// 核心一律 do_action( 'wpdo_*' )，所以單向的 tmdo_* → wpdo_* 轉發等於讓 tmdo_*
+// 契約永遠收不到事件。這裡做雙向轉發，並用共用旗標防止 A→B→A 無限迴圈與
+// listener 被觸發兩次。
+$tmdo_make_relay = static function ( string $source, string $target ): callable {
+	return static function ( ...$args ) use ( $source, $target ) {
+		$base = preg_replace( '/^(wpdo|tmdo)_/', '', $source );
+		if ( ! empty( $GLOBALS['tmdo_hook_relay_active'][ $base ] ) ) {
+			return;
+		}
+		$GLOBALS['tmdo_hook_relay_active'][ $base ] = true;
+		do_action_ref_array( $target, $args );
+		$GLOBALS['tmdo_hook_relay_active'][ $base ] = false;
+	};
+};
+
 foreach ( array(
 	'wpdo_register_fields',
 	'wpdo_register_entity_fields',
@@ -185,12 +199,29 @@ foreach ( array(
 	'wpdo_auto_promoted',
 ) as $tmdo_back_compat_hook ) {
 	$tmdo_new_hook = preg_replace( '/^wpdo_/', 'tmdo_', $tmdo_back_compat_hook );
-	add_action(
-		$tmdo_new_hook,
-		static function ( ...$args ) use ( $tmdo_back_compat_hook ) {
-			do_action_ref_array( $tmdo_back_compat_hook, $args );
-		},
-		1
-	);
+	add_action( $tmdo_new_hook, $tmdo_make_relay( $tmdo_new_hook, $tmdo_back_compat_hook ), 1 );
+	add_action( $tmdo_back_compat_hook, $tmdo_make_relay( $tmdo_back_compat_hook, $tmdo_new_hook ), 1 );
+}
+unset( $tmdo_back_compat_hook, $tmdo_new_hook, $tmdo_make_relay );
+
+// ── 函式別名（sister plugin 可能 remove_action 'plugins_loaded', 'wpdo_run'）──
+if ( ! function_exists( 'wpdo_run' ) ) {
+	/**
+	 * Back-compat shim for the old boot function name.
+	 *
+	 * @return void
+	 */
+	function wpdo_run(): void {
+		tmdo_run();
+	}
+}
+if ( ! function_exists( 'wpdo_load_textdomain' ) ) {
+	/**
+	 * Back-compat shim for the old textdomain loader name.
+	 *
+	 * @return void
+	 */
+	function wpdo_load_textdomain(): void {
+		tmdo_load_textdomain();
+	}
 }
-unset( $tmdo_back_compat_hook, $tmdo_new_hook );
diff --git a/tests/bootstrap.php b/tests/bootstrap.php
index 5b591bf..1c4a5a2 100644
--- a/tests/bootstrap.php
+++ b/tests/bootstrap.php
@@ -174,6 +174,11 @@ if ( ! function_exists( 'do_action' ) ) {
 		}
 	}
 }
+if ( ! function_exists( 'do_action_ref_array' ) ) {
+	function do_action_ref_array( string $hook, array $args ): void {
+		do_action( $hook, ...$args );
+	}
+}
 if ( ! function_exists( 'wp_next_scheduled' ) ) {
 	function wp_next_scheduled( string $hook ): int|false { return false; }
 }
diff --git a/tests/integration/bootstrap.php b/tests/integration/bootstrap.php
index 78022a7..6ed4d1b 100644
--- a/tests/integration/bootstrap.php
+++ b/tests/integration/bootstrap.php
@@ -272,6 +272,11 @@ if ( ! function_exists( 'do_action' ) ) {
 		}
 	}
 }
+if ( ! function_exists( 'do_action_ref_array' ) ) {
+	function do_action_ref_array( string $hook, array $args ): void {
+		do_action( $hook, ...$args );
+	}
+}
 
 if ( ! function_exists( 'is_admin' ) )       { function is_admin(): bool { return ! empty( $GLOBALS['_wp_is_admin'] ); } }
 if ( ! function_exists( 'is_singular' ) )    { function is_singular( $t = '' ): bool { return false; } }