diff --git a/src/ssn/streams/streamToString.ts b/src/ssn/streams/streamToString.ts
index 3917170..97cf953 100644
--- a/src/ssn/streams/streamToString.ts
+++ b/src/ssn/streams/streamToString.ts
@@ -1,9 +1,9 @@
 import * as stream from 'stream';
 import { TextDecoder } from 'util';
 
-const decoder = new TextDecoder('utf-8');
-
 export default function streamToString(inputStream: stream.Readable): Promise<string> {
+  const decoder = new TextDecoder('utf-8');
+
   return new Promise((resolve, reject) => {
     const stringParts: string[] = [];