diff --git a/server/json.ml b/server/json.ml
index b8cefe0..82704e9 100644
--- a/server/json.ml
+++ b/server/json.ml
@@ -38,24 +38,49 @@ let str_to_string s =
 
 let rec to_string j =
   match j with
-  | Num f ->
+    | Num f ->
       if float_of_int (int_of_float f) = f
       then string_of_int (int_of_float f)
       else string_of_float f
-  | Str s ->
+    | Str s ->
       str_to_string s
-  | Arr js ->
+    | Arr js ->
       "[" ^ String.concat "," (List.map to_string js) ^ "]"
-  | Rec kvs ->
+    | Rec kvs ->
       "{" ^ String.concat "," (List.map kv_to_string kvs) ^ "}"
-  | Flg b ->
+    | Flg b ->
       if b then "true" else "false"
-  | Nil ->
+    | Nil ->
       "null"
-
 and kv_to_string (k, v) =
   str_to_string k ^ ":" ^ to_string v
 
+let rec pretty_string ?indent:(indent=2) j =
+  let rec walk current j =
+    match j with
+      | Num f ->
+	if float_of_int (int_of_float f) = f
+	then string_of_int (int_of_float f)
+	else string_of_float f
+      | Str s ->
+	str_to_string s
+      | Arr js ->
+	"[" ^ String.concat ", " (List.map (walk current) js) ^ "]"
+      | Rec [] ->
+	"{}"
+      | Rec [(k, v)] ->
+	"{" ^ str_to_string k ^ ": " ^ walk current v ^ "}"
+      | Rec kvs ->
+	"{" ^ String.concat "," (List.map (kv_walk (current + indent)) kvs) ^
+	  "\n" ^ String.make current ' ' ^ "}"
+      | Flg b ->
+	if b then "true" else "false"
+      | Nil ->
+	"null"
+  and kv_walk current (k, v) =
+    "\n" ^ String.make current ' ' ^ str_to_string k ^ ": " ^ walk current v
+  in walk 0 j
+
 let accumulate_utf8 codepoint (acc, len) =
   (* Of course, at the moment, the codepoint is limited to 16 bits... *)
   if codepoint < 0x80 then