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diff --git a/tools/go_branch.sh b/tools/go_branch.sh
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+#!/bin/bash
+
+# Copyright 2019 The gVisor Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+set -eo pipefail
+
+# Discovery the package name from the go.mod file.
+declare -r module=$(cat go.mod | grep -E "^module" | cut -d' ' -f2)
+declare -r origpwd=$(pwd)
+declare -r othersrc=("go.mod" "go.sum" "AUTHORS" "LICENSE")
+
+# Check that gopath has been built.
+declare -r gopath_dir="$(pwd)/bazel-bin/gopath/src/${module}"
+if ! [ -d "${gopath_dir}" ]; then
+  echo "No gopath directory found; build the :gopath target." >&2
+  exit 1
+fi
+
+# Create a temporary working directory, and ensure that this directory and all
+# subdirectories are cleaned up upon exit.
+declare -r tmp_dir=$(mktemp -d)
+finish() {
+  cd # Leave tmp_dir.
+  rm -rf "${tmp_dir}"
+}
+trap finish EXIT
+
+# Record the current working commit.
+declare -r head=$(git describe --always)
+
+# We expect to have an existing go branch that we will use as the basis for
+# this commit. That branch may be empty, but it must exist.
+declare -r go_branch=$(git show-ref --hash origin/go)
+
+# Clone the current repository to the temporary directory, and check out the
+# current go_branch directory. We move to the new repository for convenience.
+declare -r repo_orig="$(pwd)"
+declare -r repo_new="${tmp_dir}/repository"
+git clone . "${repo_new}"
+cd "${repo_new}"
+
+# Setup the repository and checkout the branch.
+git config user.email "gvisor-bot@google.com"
+git config user.name "gVisor bot"
+git fetch origin "${go_branch}"
+git checkout -b go "${go_branch}"
+
+# Start working on a merge commit that combines the previous history with the
+# current history. Note that we don't actually want any changes yet.
+#
+# N.B. The git behavior changed at some point and the relevant flag was added
+# to allow for override, so try the only behavior first then pass the flag.
+git merge --no-commit --strategy ours ${head} || \
+  git merge --allow-unrelated-histories --no-commit --strategy ours ${head}
+
+# Sync the entire gopath_dir.
+rsync --recursive --verbose --delete --exclude .git -L "${gopath_dir}/" .
+
+# Add additional files.
+for file in "${othersrc[@]}"; do
+  cp "${origpwd}"/"${file}" .
+done
+
+# Construct a new README.md.
+cat > README.md <<EOF
+# gVisor
+
+This branch is a synthetic branch, containing only Go sources, that is
+compatible with standard Go tools. See the master branch for authoritative
+sources and tests.
+EOF
+
+# There are a few solitary files that can get left behind due to the way bazel
+# constructs the gopath target. Note that we don't find all Go files here
+# because they may correspond to unused templates, etc.
+cp "${repo_orig}"/runsc/*.go runsc/
+
+# Update the current working set and commit.
+git add . && git commit -m "Merge ${head} (automated)"
+
+# Push the branch back to the original repository.
+git remote add orig "${repo_orig}" && git push -f orig go:go