diff --git a/llvm.sh b/llvm.sh
new file mode 100755
index 0000000..aca707d
--- /dev/null
+++ b/llvm.sh
@@ -0,0 +1,25 @@
+#!/bin/bash
+function repo_init() {
+	UPSTREAM=$1
+	WORKING_DIR=$2
+	git clone --mirror $UPSTREAM $WORKING_DIR
+}
+
+function repo_update() {
+	repo_dir="$1"
+	cd $repo_dir
+	echo "==== SYNC $repo_dir START ===="
+	/usr/bin/timeout -s INT 3600 git remote -v update
+	git repack -a -b -d
+	echo "==== SYNC $repo_dir DONE ===="
+}
+
+repos=("llvm" "clang" "libcxx" "lldb" "clang-tools-extra" "polly" "zorg" "compiler-rt" "libcxxabi" "lld" "lnt")
+
+for repo in ${repos[@]}; do
+	if [[ ! -d "$TUNASYNC_WORKING_DIR/${repo}.git" ]]; then
+		echo "Initializing ${repo}.git"
+		repo_init "http://llvm.org/git/${repo}" "$TUNASYNC_WORKING_DIR/${repo}.git"
+	fi
+	repo_update "$TUNASYNC_WORKING_DIR/${repo}.git"
+done