diff --git a/hosts/pie/firefly.nix b/hosts/pie/firefly.nix
index 80c08c3..5d77a23 100644
--- a/hosts/pie/firefly.nix
+++ b/hosts/pie/firefly.nix
@@ -124,7 +124,7 @@ in {
       # See https://www.hosting.de/blog/verschluesselte-backups-mit-rclone-und-restic-in-nextcloud/
       repository = "rclone:cloud.pub.solar:/backups/FireflyIII";
       backupPrepareCommand = ''
-        docker exec -t firefly-db pg_dumpall -c -U postgres > "${backupDir}/postgres.sql"
+        ${pkgs.docker-client}/bin/docker exec -t firefly-db pg_dumpall -c -U firefly > "${backupDir}/postgres.sql"
       '';
       rcloneConfigFile = config.age.secrets."rclone-pie.conf".path;
     };