diff --git a/packages/parser/src/language/sankey/module.ts b/packages/parser/src/language/sankey/module.ts
index 6ff5d75675..f58875c79d 100644
--- a/packages/parser/src/language/sankey/module.ts
+++ b/packages/parser/src/language/sankey/module.ts
@@ -21,13 +21,13 @@ import { createSankeyParser } from './parser.js';
 /**
  * Declaration of `Sankey` services.
  */
-export type SankeyAddedServices = {
+export interface SankeyAddedServices {
   parser: {
     LangiumParser: LangiumParser;
     TokenBuilder: SankeyTokenBuilder;
     ValueConverter: SankeyValueConverter;
   };
-};
+}
 
 /**
  * Union of Langium default services and `Sankey` services.