diff --git a/ocaml-calendar.spec b/ocaml-calendar.spec
index f8c3439..4636558 100644
--- a/ocaml-calendar.spec
+++ b/ocaml-calendar.spec
@@ -4,7 +4,7 @@
 
 Name:           ocaml-calendar
 Version:        2.04
-Release:        35.1%{?dist}
+Release:        36%{?dist}
 Summary:        Objective Caml library for managing dates and times
 License:        LGPLv2
 
@@ -13,6 +13,7 @@ Source0:        https://forge.ocamlcore.org/frs/download.php/1481/calendar-2.04.
 
 Patch1:         calendar-2.03.2-enable-debug.patch
 
+BuildRequires: make
 BuildRequires:  ocaml >= 4.00.1
 BuildRequires:  ocaml-findlib-devel >= 1.3.3-3
 BuildRequires:  ocaml-ocamldoc
@@ -77,6 +78,9 @@ make install
 
 
 %changelog
+* Tue Jan 26 2021 Fedora Release Engineering <releng@fedoraproject.org> - 2.04-36
+- Rebuilt for https://fedoraproject.org/wiki/Fedora_34_Mass_Rebuild
+
 * Tue Sep 01 2020 Richard W.M. Jones <rjones@redhat.com> - 2.04-35
 - OCaml 4.11.1 rebuild