diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 233bc80d8f4b0a2ed98f97e33a6269dd6ef0d882..01fddc124d989670b28af4212074fe0183bdbc90 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -16,6 +16,10 @@
         files: tests/playbook.yml
         args:
         - tests/playbook.yml
+-   repo: https://github.com/adarnimrod/shell-pre-commit
+    sha: v0.1.0
+    hooks:
+    -   id: shell-lint
 -   repo: https://github.com/willthames/ansible-lint
     sha: 959ab0f525e9abb19cf75f34381015cf33695f61
     hooks:
diff --git a/files/backup.sh b/files/backup.sh
index bd20741d24bca2ab3f764fe96eb4cbe20565442f..cdf2e5cf4fc074f8a1757f3a02f9fc4a95659812 100644
--- a/files/backup.sh
+++ b/files/backup.sh
@@ -1,3 +1,4 @@
-#!/bin/sh -e
+#!/bin/sh
+set -eu
 cd /srv/git
 tar -cf /var/backups/git.tar.gz repositories