diff --git a/docs/developer-guide/js-api.md b/docs/developer-guide/js-api.md
index ceb65f71..2fce666b 100644
--- a/docs/developer-guide/js-api.md
+++ b/docs/developer-guide/js-api.md
@@ -6,8 +6,8 @@
 const semanticRelease = require("semantic-release");
 const { WritableStreamBuffer } = require("stream-buffers");
 
-const stdoutBuffer = WritableStreamBuffer();
-const stderrBuffer = WritableStreamBuffer();
+const stdoutBuffer = new WritableStreamBuffer();
+const stderrBuffer = new WritableStreamBuffer();
 
 try {
   const result = await semanticRelease(