argh why is this so hard

_template/build.sh

@@ -6,7 +6,12 @@ cd "$(dirname $0)"/..
 echo "$SSH_KEY" > ~/.ssh/id_rsa
 chmod 600 ~/.ssh/id_rsa
 
-./create-branches.sh
+# branch names
+DEFAULT=v3
+ROLLUP=rollup-v3
+WEBPACK=webpack-v3
 
-# force push rollup-v3 and webpack branches
-git push git@github.com:sveltejs/sapper-template.git rollup-v3 webpack-v3 -f
+./create-branches.sh $DEFAULT $ROLLUP $WEBPACK
+
+# force push rollup and webpack branches
+git push git@github.com:sveltejs/sapper-template.git $ROLLUP $WEBPACK -f

_template/create-branches.sh

@@ -1,25 +1,29 @@
 #!/bin/bash
 cd "$(dirname $0)"/..
 
-# make sure we're on master, and delete the rollup-v3 and webpack-v3 branches
-git symbolic-ref HEAD refs/heads/master
-git reset --hard
-git branch -D rollup-v3 webpack-v3
+DEFAULT=$1
+ROLLUP=$2
+WEBPACK=$3
 
-# create the rollup-v3 branch off the current master
-git checkout -b rollup-v3
+# make sure we're on master, and delete the $ROLLUP and $WEBPACK branches
+git symbolic-ref HEAD "refs/heads/$DEFAULT"
+git reset --hard
+git branch -D $ROLLUP $WEBPACK
+
+# create the $ROLLUP branch off the current master
+git checkout -b $ROLLUP
 node _template/build-pkg.js rollup
 git rm -r --cached .travis.yml _template package_template.json webpack.config.js
 git add package.json
 git commit -m 'Sapper template for Rollup'
-git symbolic-ref HEAD refs/heads/master
+git symbolic-ref HEAD "refs/heads/$DEFAULT"
 git reset --hard
 
-# create the webpack-v3 branch off the current master
-git checkout -b webpack-v3
+# create the $WEBPACK branch off the current master
+git checkout -b $WEBPACK
 node _template/build-pkg.js webpack
 git rm -r --cached .travis.yml _template package_template.json rollup.config.js
 git add package.json
 git commit -m 'Sapper template for webpack'
-git symbolic-ref HEAD refs/heads/master
+git symbolic-ref HEAD "refs/heads/$DEFAULT"
 git reset --hard