diff --git a/src/request.lisp b/src/request.lisp
index abe32f7..200156b 100644
--- a/src/request.lisp
+++ b/src/request.lisp
@@ -73,7 +73,9 @@
         (setf uri (getf env :request-uri)))
       (unless uri-scheme
         ;; for some reason, it is called url-scheme in the environment plist :(
-        (setf uri-scheme (getf env :url-scheme))))
+        (setf uri-scheme (getf env :url-scheme)))
+      (unless content-type
+        (setf content-type "application/octet-stream")))
 
     ;; Cookies
     (unless (request-cookies req)