diff --git a/lib/response.ml b/lib/response.ml
index 6b3a8d5..de1a655 100644
--- a/lib/response.ml
+++ b/lib/response.ml
@@ -89,7 +89,6 @@ let copy_file ?version ?(headers = Headers.empty) path =
     with
     | exn -> Result.error (`Exn exn)
   in
-
   let headers =
     let mime = Magic_mime.lookup path in
     Headers.(add_unless_exists headers Well_known.content_type mime)
diff --git a/multipart_test/multipart_test.ml b/multipart_test/multipart_test.ml
index e58f0fa..4b4ad93 100644
--- a/multipart_test/multipart_test.ml
+++ b/multipart_test/multipart_test.ml
@@ -4,15 +4,12 @@ let content_type =
   "multipart/form-data; boundary=----WebKitFormBoundaryVuTaDGWRcduyfmAv"
 
 let multipart_request_body n =
-  Format.asprintf
-    {|------WebKitFormBoundaryVuTaDGWRcduyfmAv
-Content-Disposition: form-data; name="picture.png"; filename="picture.png"
-Content-Type: image/png
-
-%s
+    {|------WebKitFormBoundaryVuTaDGWRcduyfmAv|}^"\r"^{|
+Content-Disposition: form-data; name="picture.png"; filename="picture.png"|}^"\r"^{|
+Content-Type: image/png|}^"\r\n\r\n"^
+(String.make n 'a')^"\r"^{|
 ------WebKitFormBoundaryVuTaDGWRcduyfmAv--
 |}
-    (String.make n 'a')
 
 let multipart_request_body_chunks payload =
   let continue = ref true in