diff --git a/config.ml b/config.ml
index 46855e5..614f939 100644
--- a/config.ml
+++ b/config.ml
@@ -38,9 +38,11 @@ module Addrs = struct
     &> (str |> name)
 end
 
+let to_list_loose = function `List list -> list | _ -> []
+
 let to_int_list json =
   let open Yojson.Basic.Util in
-  json |> to_list |> List.map to_int
+  json |> to_list_loose |> List.map to_int
 
 module PayloadRule = struct
   module Tcp = struct
@@ -74,9 +76,7 @@ module PayloadRule = struct
     | _ -> assert false
 end
 
-let to_addr_list json =
-  let open Yojson.Basic.Util in
-  json |> to_list |> List.map Addrs.of_json
+let to_addr_list json = json |> to_list_loose |> List.map Addrs.of_json
 
 module Rule = struct
   type t = { src : Addrs.t list; dest : Addrs.t list; payload : PayloadRule.t }
@@ -98,5 +98,7 @@ let zones_of_json json =
 let of_json json =
   let open Yojson.Basic.Util in
   let zones = json |> member "zones" |> zones_of_json in
-  let rules = json |> member "rules" |> to_list |> List.map Rule.of_json in
+  let rules =
+    json |> member "rules" |> to_list_loose |> List.map Rule.of_json
+  in
   { zones; rules }