diff --git a/10/entrypoint.sh b/10/entrypoint.sh
index 119e8b5..78d2a8c 100755
--- a/10/entrypoint.sh
+++ b/10/entrypoint.sh
@@ -7,6 +7,6 @@ if [[ $@ == *crond* ]] && [ -z "$CRON_SCHEDULE" ]; then
 fi
 
 # Write cron schedule
-echo "$CRON_SCHEDULE python3 -u /backup/backup.py > /dev/stdout" > /var/spool/cron/crontabs/root
+echo "$CRON_SCHEDULE python3 -u /backup/backup.py > /dev/stdout" | crontab -
 
 exec "$@"
diff --git a/11/entrypoint.sh b/11/entrypoint.sh
index 119e8b5..78d2a8c 100755
--- a/11/entrypoint.sh
+++ b/11/entrypoint.sh
@@ -7,6 +7,6 @@ if [[ $@ == *crond* ]] && [ -z "$CRON_SCHEDULE" ]; then
 fi
 
 # Write cron schedule
-echo "$CRON_SCHEDULE python3 -u /backup/backup.py > /dev/stdout" > /var/spool/cron/crontabs/root
+echo "$CRON_SCHEDULE python3 -u /backup/backup.py > /dev/stdout" | crontab -
 
 exec "$@"
diff --git a/12/entrypoint.sh b/12/entrypoint.sh
index 119e8b5..78d2a8c 100755
--- a/12/entrypoint.sh
+++ b/12/entrypoint.sh
@@ -7,6 +7,6 @@ if [[ $@ == *crond* ]] && [ -z "$CRON_SCHEDULE" ]; then
 fi
 
 # Write cron schedule
-echo "$CRON_SCHEDULE python3 -u /backup/backup.py > /dev/stdout" > /var/spool/cron/crontabs/root
+echo "$CRON_SCHEDULE python3 -u /backup/backup.py > /dev/stdout" | crontab -
 
 exec "$@"
diff --git a/13/entrypoint.sh b/13/entrypoint.sh
index 119e8b5..78d2a8c 100755
--- a/13/entrypoint.sh
+++ b/13/entrypoint.sh
@@ -7,6 +7,6 @@ if [[ $@ == *crond* ]] && [ -z "$CRON_SCHEDULE" ]; then
 fi
 
 # Write cron schedule
-echo "$CRON_SCHEDULE python3 -u /backup/backup.py > /dev/stdout" > /var/spool/cron/crontabs/root
+echo "$CRON_SCHEDULE python3 -u /backup/backup.py > /dev/stdout" | crontab -
 
 exec "$@"
diff --git a/14/entrypoint.sh b/14/entrypoint.sh
index 119e8b5..78d2a8c 100755
--- a/14/entrypoint.sh
+++ b/14/entrypoint.sh
@@ -7,6 +7,6 @@ if [[ $@ == *crond* ]] && [ -z "$CRON_SCHEDULE" ]; then
 fi
 
 # Write cron schedule
-echo "$CRON_SCHEDULE python3 -u /backup/backup.py > /dev/stdout" > /var/spool/cron/crontabs/root
+echo "$CRON_SCHEDULE python3 -u /backup/backup.py > /dev/stdout" | crontab -
 
 exec "$@"
diff --git a/15/entrypoint.sh b/15/entrypoint.sh
index 119e8b5..78d2a8c 100755
--- a/15/entrypoint.sh
+++ b/15/entrypoint.sh
@@ -7,6 +7,6 @@ if [[ $@ == *crond* ]] && [ -z "$CRON_SCHEDULE" ]; then
 fi
 
 # Write cron schedule
-echo "$CRON_SCHEDULE python3 -u /backup/backup.py > /dev/stdout" > /var/spool/cron/crontabs/root
+echo "$CRON_SCHEDULE python3 -u /backup/backup.py > /dev/stdout" | crontab -
 
 exec "$@"
diff --git a/16/entrypoint.sh b/16/entrypoint.sh
index 119e8b5..78d2a8c 100755
--- a/16/entrypoint.sh
+++ b/16/entrypoint.sh
@@ -7,6 +7,6 @@ if [[ $@ == *crond* ]] && [ -z "$CRON_SCHEDULE" ]; then
 fi
 
 # Write cron schedule
-echo "$CRON_SCHEDULE python3 -u /backup/backup.py > /dev/stdout" > /var/spool/cron/crontabs/root
+echo "$CRON_SCHEDULE python3 -u /backup/backup.py > /dev/stdout" | crontab -
 
 exec "$@"
diff --git a/Makefile b/Makefile
index c3bebf3..aee3226 100644
--- a/Makefile
+++ b/Makefile
@@ -1,2 +1,2 @@
 update:
-	python update.py
+	python3 update.py
diff --git a/template/entrypoint.sh b/template/entrypoint.sh
index 119e8b5..78d2a8c 100755
--- a/template/entrypoint.sh
+++ b/template/entrypoint.sh
@@ -7,6 +7,6 @@ if [[ $@ == *crond* ]] && [ -z "$CRON_SCHEDULE" ]; then
 fi
 
 # Write cron schedule
-echo "$CRON_SCHEDULE python3 -u /backup/backup.py > /dev/stdout" > /var/spool/cron/crontabs/root
+echo "$CRON_SCHEDULE python3 -u /backup/backup.py > /dev/stdout" | crontab -
 
 exec "$@"