diff --git a/src/interfaces/source.ts b/src/interfaces/source.ts
index d2e7d6c..602a669 100644
--- a/src/interfaces/source.ts
+++ b/src/interfaces/source.ts
@@ -98,6 +98,7 @@ export class Site {
   actor_id: string;
   last_refreshed_at: string;
   inbox_url: string;
+  private_key: Option<string>;
   public_key: string;
   instance_id: number;
 }