diff --git a/ai/compat_1.7.nut b/ai/compat_1.7.nut
new file mode 100644
--- /dev/null
+++ b/ai/compat_1.7.nut
@@ -0,0 +1,22 @@
+/*
+ * This file is part of OpenTTD.
+ * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
+ * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+AILog.Info("1.7 API compatibility in effect.");
+
+/* 1.9 adds a vehicle type parameter. */
+AIBridge._GetName <- AIBridge.GetName;
+AIBridge.GetName <- function(bridge_id)
+{
+	return AIBridge._GetName(bridge_id, AIVehicle.VT_RAIL);
+}
+
+/* 1.9 adds parent_group_id to CreateGroup function */
+AIGroup._CreateGroup <- AIGroup.CreateGroup;
+AIGroup.CreateGroup <- function(vehicle_type)
+{
+	return AIGroup._CreateGroup(vehicle_type, AIGroup.GROUP_INVALID);
+}