diff --git a/rebase.sh b/rebase.sh
index 4612cc2..e1065f0 100755
--- a/rebase.sh
+++ b/rebase.sh
@@ -1,7 +1,29 @@
 #!/bin/bash
+
+# We always do a rebase to new upstream's tarball for Fedora Rawhide.
+#
+# For non-Rawhide Fedora releases, we can sometimes backport specific patches,
+# if the rebase is not possible.
+#
+# This scripts automates this process.
+
+# Since we are operating in a dist-git repository where we can't fix things with
+# --force-push if something goes wrong, we need to be extra careful and exit
+# immediately if something fails.
 set -e
-curl https://raw.githubusercontent.com/fedora-sysv/initscripts/master/initscripts.spec -o initscripts.spec
-git add initscripts.spec
+
+curl https://raw.githubusercontent.com/fedora-sysv/initscripts/master/initscripts.spec -o initscripts.spec || exit 1
 spectool -g initscripts.spec
-fedpkg new-sources $(basename $(spectool -S -l initscripts.spec | awk '{print $2;}'))
-git commit -m $(grep Version initscripts.spec | awk '{print $2;}')
+
+# Make a local scratch build in mock first. If it fails, do not upload new tarball!
+srpm_file="$(fedpkg srpm | grep -i "wrote" | cut -d ':' -f 2)"
+arch="$(uname -p)"
+
+mock -r "fedora-rawhide-${arch}" "${srpm_file}" || exit 2
+
+# Scratch build passed, the build should pass in Koji as well. Let's proceed:
+fedpkg new-sources "$(basename $(spectool -S -l initscripts.spec | gawk '{print $2;}'))" || exit 3
+git add initscripts.spec
+git commit -m "$(grep Version initscripts.spec | gawk '{print $2;}')"
+
+git show