diff --git a/Makefile b/Makefile
index 4098eb9..d42d3f0 100644
--- a/Makefile
+++ b/Makefile
@@ -23,11 +23,12 @@ test: setup testonly
 testonly:
 	raco test -p $(PACKAGES)
 
+PROTOCOLS_BRANCH=main
 pull-protocols:
 	git subtree pull -P syndicate/private/protocols \
 		-m 'Merge latest changes from the syndicate-protocols repository' \
 		git@git.syndicate-lang.org:syndicate-lang/syndicate-protocols \
-		main
+		$(PROTOCOLS_BRANCH)
 
 fixcopyright:
 	-fixcopyright.rkt --preset-racket LGPL-3.0-or-later