diff --git a/cli/src/commands/script/script.ts b/cli/src/commands/script/script.ts
index 0bca28c294..820bada9b3 100644
--- a/cli/src/commands/script/script.ts
+++ b/cli/src/commands/script/script.ts
@@ -314,7 +314,8 @@ export async function handleFile(
             continue;
           }
           log.info(`Adding file: ${file.path.substring(1)}`);
-          const fil = new File([file.contents as BlobPart], file.path.substring(1));
+          // .slice() creates new ArrayBuffer, needed for cross-platform compatibility
+          const fil = new File([file.contents.slice()], file.path.substring(1));
           tarball.append(fil);
         }
         const endTime = performance.now();
@@ -541,8 +542,8 @@ async function streamToBlob(stream: ReadableStream<Uint8Array>): Promise<Blob> {
     chunks.push(value);
   }
 
-  // Create a Blob from the chunks
-  const blob = new Blob(chunks as BlobPart[]);
+  // Create a Blob from the chunks (.map with slice for cross-platform compatibility)
+  const blob = new Blob(chunks.map(c => c.slice()));
   return blob;
 }