diff --git a/lib/migration_generator/migration_generator.ex b/lib/migration_generator/migration_generator.ex
index e305cb0..be8565d 100644
--- a/lib/migration_generator/migration_generator.ex
+++ b/lib/migration_generator/migration_generator.ex
@@ -123,11 +123,11 @@ defmodule AshPostgres.MigrationGenerator do
         {module, migration_name} =
           case to_install do
             [single] ->
-              {"install_#{single}", "#{timestamp(true)}_install_#{single}.exs"}
+              {"install_#{single}", "#{timestamp(true)}_install_#{single}_extension"}
 
             multiple ->
               {"install_#{Enum.count(multiple)}_extensions",
-               "#{timestamp(true)}_install_#{Enum.count(multiple)}_extensions.exs"}
+               "#{timestamp(true)}_install_#{Enum.count(multiple)}_extensions"}
           end
 
         migration_file =