diff --git a/docker/init.sh b/docker/init.sh
index 722df3700..49b53d646 100755
--- a/docker/init.sh
+++ b/docker/init.sh
@@ -2,7 +2,7 @@
 
 #backend
 gitMaster="\.\.\/\.git\/refs\/heads\/master"
-git ls-remote https://github.com/mempool/mempool.git $1 | awk '{ print $1}' > ./backend/master
+git ls-remote https://github.com/mempool/mempool.git "$1^{}" | awk '{ print $1}' > ./backend/master
 cp ./docker/backend/* ./backend/
 sed -i "s/${gitMaster}/master/g" ./backend/src/api/backend-info.ts