diff --git a/wagtail/contrib/wagtailapi/serializers.py b/wagtail/contrib/wagtailapi/serializers.py
index c0f26101c..4cd323e16 100644
--- a/wagtail/contrib/wagtailapi/serializers.py
+++ b/wagtail/contrib/wagtailapi/serializers.py
@@ -3,13 +3,13 @@ from __future__ import absolute_import
 from collections import OrderedDict
 
 from django.db import models
-from django.utils.encoding import force_text
 
 from modelcluster.models import get_all_child_relations
 
 from taggit.managers import TaggableManager
 
 from rest_framework.serializers import BaseSerializer
+from rest_framework.fields import Field, ReadOnlyField
 
 from wagtail.utils.compat import get_related_model
 from wagtail.wagtailcore.models import Page
@@ -18,30 +18,14 @@ from wagtail.wagtailcore import fields as wagtailcore_fields
 from .utils import ObjectDetailURL, URLPath, BadRequestError, pages_for_site
 
 
-class Field(object):
-    def __init__(self, field_name):
-        self.field_name = field_name
-
-    def get_attribute(self, instance):
-        return getattr(instance, self.field_name)
-
-    def to_representation(self, value):
-        return value
-
-
-class AttrField(Field):
-    def to_representation(self, value):
-        return force_text(value, strings_only=True)
-
-
 class ChildRelationField(Field):
-    def __init__(self, field_name, fields):
-        self.field_name = field_name
-        self.fields = fields
+    def __init__(self, *args, **kwargs):
+        self.child_fields = kwargs.pop('child_fields')
+        super(ChildRelationField, self).__init__(*args, **kwargs)
 
     def to_representation(self, value):
         return [
-            dict(get_api_data(child_object, self.fields))
+            dict(get_api_data(child_object, self.child_fields))
             for child_object in value.all()
         ]
 
@@ -82,7 +66,7 @@ def get_serializer_fields(model, fields):
     for field_name in fields:
         # Check child relations
         if field_name in child_relations and hasattr(child_relations[field_name], 'api_fields'):
-            yield ChildRelationField(field_name, child_relations[field_name].api_fields)
+            yield field_name, ChildRelationField, {'child_fields': child_relations[field_name].api_fields}
             continue
 
         # Check django fields
@@ -90,13 +74,13 @@ def get_serializer_fields(model, fields):
             field = model._meta.get_field(field_name)
 
             if field.rel and isinstance(field.rel, models.ManyToOneRel):
-                yield RelatedObjectField(field_name)
+                yield field_name, RelatedObjectField, {}
             elif isinstance(field, wagtailcore_fields.StreamField):
-                yield StreamField(field_name)
+                yield field_name, StreamField, {}
             elif isinstance(field, TaggableManager):
-                yield TagsField(field_name)
+                yield field_name, TagsField, {}
             else:
-                yield AttrField(field_name)
+                yield field_name, ReadOnlyField, {}
 
             continue
         except models.fields.FieldDoesNotExist:
@@ -104,14 +88,17 @@ def get_serializer_fields(model, fields):
 
         # Check attributes
         if hasattr(model, field_name):
-            yield AttrField(field_name)
+            yield field_name, ReadOnlyField, {}
             continue
 
 
 def get_api_data(obj, fields):
     serializer_fields = get_serializer_fields(type(obj), fields)
 
-    for field in serializer_fields:
+    for field_name, field_class, field_kwargs in serializer_fields:
+        field = field_class(**field_kwargs)
+        field.bind(field_name, None)
+
         value = field.get_attribute(obj)
 
         if value is not None: