diff --git a/json_serialization/reader.nim b/json_serialization/reader.nim
index 4ab9749..e89cc52 100644
--- a/json_serialization/reader.nim
+++ b/json_serialization/reader.nim
@@ -17,10 +17,6 @@ type
     encounteredField*: cstring
     deserializedType*: cstring
 
-  CustomSerializationError* = object of JsonReaderError
-    deserializedField*: string
-    innerException*: ref CatchableError
-
   ExpectedTokenCategory* = enum
     etBool = "bool literal"
     etInt = "integer"
@@ -33,6 +29,10 @@ type
     etCurrlyLe = "object start bracket"
     etCurrlyRi = "object end bracket"
 
+  GenericJsonReaderError* = object of JsonReaderError
+    deserializedField*: string
+    innerException*: ref CatchableError
+
   UnexpectedToken* = object of JsonReaderError
     encountedToken*: TokKind
     expectedToken*: ExpectedTokenCategory
@@ -46,8 +46,8 @@ method formatMsg*(err: ref UnexpectedField, filename: string): string =
 method formatMsg*(err: ref UnexpectedToken, filename: string): string =
   fmt"{filename}({err.line}, {err.col}) Unexpected token '{err.encountedToken}' in place of '{err.expectedToken}'"
 
-method formatMsg*(err: ref CustomSerializationError, filename: string): string =
-  fmt"{filename}({err.line}, {err.col}) Custom serialization exception while deserializing '{err.deserializedField}': [{err.innerException.name}] {err.innerException.msg}"
+method formatMsg*(err: ref GenericJsonReaderError, filename: string): string =
+  fmt"{filename}({err.line}, {err.col}) Exception encountered while deserializing '{err.deserializedField}': [{err.innerException.name}] {err.innerException.msg}"
 
 template init*(T: type JsonReader, stream: ByteStreamVar, mode = defaultJsonMode): auto =
   init JsonReader, AsciiStreamVar(stream), mode
@@ -70,10 +70,12 @@ proc raiseUnexpectedField(r: JsonReader, fieldName, deserializedType: cstring) =
   ex.deserializedType = deserializedType
   raise ex
 
-proc readValueFailed*(r: JsonReader,
-                      Record: type, fieldName: string, field: var auto,
-                      err: ref CatchableError) =
-  var ex = new CustomSerializationError
+proc handleReadException*(r: JsonReader,
+                          Record: type,
+                          fieldName: string,
+                          field: var auto,
+                          err: ref CatchableError) =
+  var ex = new GenericJsonReaderError
   ex.assignLineNumber(r)
   ex.deserializedField = fieldName
   ex.innerException = err
diff --git a/json_serialization/writer.nim b/json_serialization/writer.nim
index f164a00..dae4e14 100644
--- a/json_serialization/writer.nim
+++ b/json_serialization/writer.nim
@@ -125,6 +125,8 @@ proc writeArray[T](w: var JsonWriter, elements: openarray[T]) =
   writeIterable(w, elements)
 
 proc writeValue*(w: var JsonWriter, value: auto) =
+  mixin enumInstanceSerializedFields
+
   template addChar(c) =
     append c
 
@@ -161,7 +163,6 @@ proc writeValue*(w: var JsonWriter, value: auto) =
         # TODO: Should this really use a decimal representation?
         # Or perhaps $ord(c) returns hex?
         # This is potentially a bug in Nim's json module.
-        # In any case, we can call appendNumber here.
         append $ord(c)
       of '\\': addPrefixSlash '\\'
       else: addChar c
@@ -170,16 +171,16 @@ proc writeValue*(w: var JsonWriter, value: auto) =
   elif value is bool:
     append if value: "true" else: "false"
   elif value is enum:
-    w.stream.appendNumber ord(value)
+    w.stream.append $ord(value)
   elif value is SomeInteger:
-    w.stream.appendNumber value
+    w.stream.append $value
   elif value is SomeFloat:
     append $value
   elif value is (seq or array):
     w.writeArray(value)
   elif value is (object or tuple):
     w.beginRecord(type(value))
-    value.serializeFields(k, v):
+    value.enumInstanceSerializedFields(k, v):
       w.writeField k, v
     w.endRecord()
   else:
diff --git a/tests/test_serialization.nim b/tests/test_serialization.nim
index c6f535a..0560443 100644
--- a/tests/test_serialization.nim
+++ b/tests/test_serialization.nim
@@ -1,5 +1,6 @@
 import
   strutils, unittest,
+  serialization/object_serialization,
   serialization/testing/generic_suite,
   ../json_serialization, ./utils,
   ../json_serialization/std/[options, sets]
@@ -12,10 +13,11 @@ type
     x: int
     y: string
     distance: Meter
+    ignored: int
 
   Foo = object
     i: int
-    b: Bar
+    b {.dontSerialize.}: Bar
     s: string
 
   Bar = object
@@ -41,6 +43,8 @@ template reject(code) =
 
 borrowSerialization(Meter, int)
 
+Simple.setSerializedFields distance, x, y
+
 proc `==`(lhs, rhs: Meter): bool =
   int(lhs) == int(rhs)
 
@@ -74,21 +78,21 @@ suite "toJson tests":
     var s = Simple(x: 10, y: "test", distance: Meter(20))
 
     check:
-      s.toJson == """{"x":10,"y":"test","distance":20}"""
-      s.toJson(typeAnnotations = true) == """{"$type":"Simple","x":10,"y":"test","distance":20}"""
+      s.toJson == """{"distance":20,"x":10,"y":"test"}"""
+      s.toJson(typeAnnotations = true) == """{"$type":"Simple","distance":20,"x":10,"y":"test"}"""
       s.toJson(pretty = true) == dedent"""
         {
+          "distance": 20,
           "x": 10,
-          "y": "test",
-          "distance": 20
+          "y": "test"
         }
       """
 
   test "handle missing fields":
     let json = dedent"""
         {
-          "y": "test",
-          "distance": 20
+          "distance": 20,
+          "y": "test"
         }
       """
 
@@ -135,8 +139,8 @@ suite "toJson tests":
       h1 = HoldsOption(o: some Simple(x: 1, y: "2", distance: Meter(3)))
       h2 = HoldsOption(r: newSimple(1, "2", Meter(3)))
 
-    Json.roundtripTest h1, """{"r":null,"o":{"x":1,"y":"2","distance":3}}"""
-    Json.roundtripTest h2, """{"r":{"x":1,"y":"2","distance":3},"o":null}"""
+    Json.roundtripTest h1, """{"r":null,"o":{"distance":3,"x":1,"y":"2"}}"""
+    Json.roundtripTest h2, """{"r":{"distance":3,"x":1,"y":"2"},"o":null}"""
 
   test "Set types":
     type HoldsSet = object