diff --git a/backup-tar/sources_anna b/backup-tar/sources_anna
index 5f32d8ce0c89fcb8f8abbcdfc4092e6ae96c49d0..ee47c8de7cc882b8f8f8f959c849aac891fc5f56 100644
--- a/backup-tar/sources_anna
+++ b/backup-tar/sources_anna
@@ -1,6 +1,9 @@
-POSTGRES=/root/backup/postgres
-mkdir -p $POSTGRES
-sudo -u postgres pg_dumpall | xz -9 -T2 > $POSTGRES/postgres-anna.dump.xz
+(
+    set -euo pipefail
+    POSTGRES=/root/backup/postgres
+    mkdir -p $POSTGRES
+    (cd ~postgres; sudo -u postgres pg_dumpall) | xz -9 -T2 > $POSTGRES/postgres-anna.dump.xz
+)
 
 SOURCES="/srv/pdsbot/ /root/backup/postgres/"