diff --git a/scripts/prepare/generate.ts b/scripts/prepare/generate.ts
index bcc19b4a49..929cdc00f6 100644
--- a/scripts/prepare/generate.ts
+++ b/scripts/prepare/generate.ts
@@ -37,6 +37,7 @@ async function loadScripts(): Promise<readonly [Writer, Transformer]> {
       exports,
       module: { exports },
       require: req,
+      process: { env: {} },
     };
     script.runInNewContext(ctx);