diff --git a/tools/repo/check.d/10-crontabs.sh b/tools/repo/check.d/10-crontabs.sh
index 23fea1d..7c0e2cc 100755
--- a/tools/repo/check.d/10-crontabs.sh
+++ b/tools/repo/check.d/10-crontabs.sh
@@ -1,14 +1,24 @@
-#!/bin/sh
+#!/bin/bash
 
 set -e
 for cronfile in skel/etc/cron.d/*; do
+    basename=$(basename $cronfile)
+    sum=$(sha1sum $cronfile)
+    if [ -f .neb/cron/$basename-sum.txt ]; then
+        [ "$(cat .neb/cron/$basename-sum.txt)" = "$sum" ] && continue
+    else
+        mkdir -p .neb/cron
+    fi
+
     echo "checking $cronfile..."
     if ! echo "$cronfile" | grep -q "."; then
         echo "$cronfile: crontabs may not have an extension"
         exit 1
     fi
-    if ! [ $(tail -c1 "$cronfile" | wc -l) -gt 0 ]; then
-        echo "$cronfile: crontabs must end with a newline"
+    if ! crontab -T $cronfile &> /dev/null; then
+        echo "$cronfile: crontab syntax error"
         exit 1
     fi
+
+    echo "$sum" > .neb/cron/$basename-sum.txt
 done
\ No newline at end of file