diff --git a/nixos/tests/postgresql/wal2json.nix b/nixos/tests/postgresql/wal2json.nix
index 511b1a7a2e8c..e1f8cf248c54 100644
--- a/nixos/tests/postgresql/wal2json.nix
+++ b/nixos/tests/postgresql/wal2json.nix
@@ -22,6 +22,7 @@ let
               wal_level = "logical";
               max_replication_slots = "10";
               max_wal_senders = "10";
+              output_plugin_libraries = "wal2json";
             };
           };
         };