diff --git a/hack/verify-codegen.sh b/hack/verify-codegen.sh
index 6d157bfb5837..c184b108ccd2 100755
--- a/hack/verify-codegen.sh
+++ b/hack/verify-codegen.sh
@@ -14,42 +14,46 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+source "$(dirname $(readlink -f ${BASH_SOURCE}))/../test/library.sh"
+
 set -o errexit
 set -o nounset
 set -o pipefail
 
-SERVING_ROOT=$(dirname "${BASH_SOURCE}")/..
-
-DIFFROOT="${SERVING_ROOT}"
-TMP_DIFFROOT="${SERVING_ROOT}/_tmp"
-_tmp="${SERVING_ROOT}/_tmp"
+readonly TMP_DIFFROOT="$(mktemp -d -p ${SERVING_ROOT_DIR})"
 
 cleanup() {
-  rm -rf "${_tmp}"
+  rm -rf "${TMP_DIFFROOT}"
 }
 
 trap "cleanup" EXIT SIGINT
 
 cleanup
 
+# Save working tree state
 mkdir -p "${TMP_DIFFROOT}/pkg"
-cp -a "${DIFFROOT}/pkg"/* "${TMP_DIFFROOT}/pkg"
+cp -aR "${SERVING_ROOT_DIR}/Gopkg.lock" "${SERVING_ROOT_DIR}/pkg" "${SERVING_ROOT_DIR}/vendor" "${TMP_DIFFROOT}"
 
 # We symlink a few testdata files from config, so copy it as well.
 mkdir -p "${TMP_DIFFROOT}/config"
-cp -a "${DIFFROOT}/config"/* "${TMP_DIFFROOT}/config"
+cp -a "${SERVING_ROOT_DIR}/config"/* "${TMP_DIFFROOT}/config"
 
 # TODO(mattmoor): We should be able to rm -rf pkg/client/ and vendor/
 
-"${SERVING_ROOT}/hack/update-codegen.sh"
-echo "Diffing ${DIFFROOT} against freshly generated codegen"
+"${SERVING_ROOT_DIR}/hack/update-codegen.sh"
+echo "Diffing ${SERVING_ROOT_DIR} against freshly generated codegen"
 ret=0
-diff -Naupr "${DIFFROOT}/pkg" "${TMP_DIFFROOT}/pkg" || ret=$?
-cp -a "${TMP_DIFFROOT}/pkg"/* "${DIFFROOT}/pkg"
+diff -Naupr "${SERVING_ROOT_DIR}/pkg" "${TMP_DIFFROOT}/pkg" || ret=$?
+
+# Restore working tree state
+rm -fr "${TMP_DIFFROOT}/config"
+rm -fr "${SERVING_ROOT_DIR}/Gopkg.lock" "${SERVING_ROOT_DIR}/pkg" "${SERVING_ROOT_DIR}/vendor"
+cp -aR "${TMP_DIFFROOT}"/* "${SERVING_ROOT_DIR}"
+
 if [[ $ret -eq 0 ]]
 then
-  echo "${DIFFROOT} up to date."
+  echo "${SERVING_ROOT_DIR} up to date."
 else
-  echo "ERROR: ${DIFFROOT} is out of date. Please run ./hack/update-codegen.sh"
+  echo "ERROR: ${SERVING_ROOT_DIR} is out of date. Please run ./hack/update-codegen.sh"
   exit 1
 fi