diff --git a/packages/drizzle-driver/src/utils/schema.ts b/packages/drizzle-driver/src/utils/schema.ts
index 772d66e7..6a939f9f 100644
--- a/packages/drizzle-driver/src/utils/schema.ts
+++ b/packages/drizzle-driver/src/utils/schema.ts
@@ -154,5 +154,5 @@ export class DrizzleAppSchema<
     this.types = {} as SchemaTableType<Expand<TablesFromSchemaEntries<T>>>;
   }
 
-  types: SchemaTableType<Expand<TablesFromSchemaEntries<T>>>;
+  readonly types: SchemaTableType<Expand<TablesFromSchemaEntries<T>>>;
 }