diff --git a/include/ArduinoJson/ForwardDeclarations.hpp b/include/ArduinoJson/ForwardDeclarations.hpp
index fc9a188e..a3ebf3a5 100644
--- a/include/ArduinoJson/ForwardDeclarations.hpp
+++ b/include/ArduinoJson/ForwardDeclarations.hpp
@@ -6,8 +6,6 @@
 
 #pragma once
 
-// TODO: cleanup
-
 namespace ArduinoJson {
 class JsonArray;
 class JsonArrayConstIterator;
diff --git a/include/ArduinoJson/Internals/CompactJsonWriter.hpp b/include/ArduinoJson/Internals/CompactJsonWriter.hpp
index edd1e15b..abc39027 100644
--- a/include/ArduinoJson/Internals/CompactJsonWriter.hpp
+++ b/include/ArduinoJson/Internals/CompactJsonWriter.hpp
@@ -10,6 +10,7 @@
 
 namespace ArduinoJson {
 namespace Internals {
+
 class CompactJsonWriter : public JsonWriter {
  public:
   explicit CompactJsonWriter(Print *sink) : JsonWriter(sink) {}
diff --git a/include/ArduinoJson/Internals/JsonArrayNode.hpp b/include/ArduinoJson/Internals/JsonArrayNode.hpp
index 842bb443..13c3a62e 100644
--- a/include/ArduinoJson/Internals/JsonArrayNode.hpp
+++ b/include/ArduinoJson/Internals/JsonArrayNode.hpp
@@ -14,16 +14,10 @@ namespace Internals {
 
 class JsonArrayNode {
  public:
-  static JsonArrayNode* createFrom(JsonBuffer* buffer) {
-    void* ptr = buffer->alloc(sizeof(JsonArrayNode));
-    return ptr ? new (ptr) JsonArrayNode() : NULL;
-  }
+  JsonArrayNode() : next(0) {}
 
   JsonArrayNode* next;
   JsonValue value;
-
- private:
-  JsonArrayNode() : next(0) {}
 };
 }
 }
diff --git a/include/ArduinoJson/Internals/JsonObjectNode.hpp b/include/ArduinoJson/Internals/JsonObjectNode.hpp
index e3be8178..6ea76f7d 100644
--- a/include/ArduinoJson/Internals/JsonObjectNode.hpp
+++ b/include/ArduinoJson/Internals/JsonObjectNode.hpp
@@ -14,16 +14,10 @@ namespace Internals {
 
 class JsonObjectNode {
  public:
-  static JsonObjectNode* createFrom(JsonBuffer* buffer, const char* key) {
-    void* ptr = buffer->alloc(sizeof(JsonObjectNode));
-    return ptr ? new (ptr) JsonObjectNode(key) : NULL;
-  }
+  JsonObjectNode(const char* k) : pair(k), next(NULL) {}
 
   JsonPair pair;
   JsonObjectNode* next;
-
- private:
-  JsonObjectNode(const char* k) : pair(k), next(NULL) {}
 };
 }
 }
diff --git a/include/ArduinoJson/Internals/JsonSerializer.hpp b/include/ArduinoJson/Internals/JsonSerializer.hpp
index 2b815904..bba785cd 100644
--- a/include/ArduinoJson/Internals/JsonSerializer.hpp
+++ b/include/ArduinoJson/Internals/JsonSerializer.hpp
@@ -23,4 +23,4 @@ class JsonSerializer {
   JsonWriter &_writer;
 };
 }
-}
\ No newline at end of file
+}
diff --git a/include/ArduinoJson/Internals/JsonWriter.hpp b/include/ArduinoJson/Internals/JsonWriter.hpp
index 906e0fb7..aa25fab9 100644
--- a/include/ArduinoJson/Internals/JsonWriter.hpp
+++ b/include/ArduinoJson/Internals/JsonWriter.hpp
@@ -10,6 +10,7 @@
 
 namespace ArduinoJson {
 namespace Internals {
+
 class JsonWriter {
  public:
   explicit JsonWriter(Print *sink) : _sink(sink), _length(0) {}
diff --git a/include/ArduinoJson/Internals/PrettyJsonWriter.hpp b/include/ArduinoJson/Internals/PrettyJsonWriter.hpp
index 7975c641..ec2ea27a 100644
--- a/include/ArduinoJson/Internals/PrettyJsonWriter.hpp
+++ b/include/ArduinoJson/Internals/PrettyJsonWriter.hpp
@@ -11,6 +11,7 @@
 
 namespace ArduinoJson {
 namespace Internals {
+
 class PrettyJsonWriter : public JsonWriter {
  public:
   explicit PrettyJsonWriter(IndentedPrint *sink)
diff --git a/include/ArduinoJson/Internals/QuotedString.hpp b/include/ArduinoJson/Internals/QuotedString.hpp
index f144c658..311ed195 100644
--- a/include/ArduinoJson/Internals/QuotedString.hpp
+++ b/include/ArduinoJson/Internals/QuotedString.hpp
@@ -10,10 +10,10 @@
 
 namespace ArduinoJson {
 namespace Internals {
+
 class QuotedString {
  public:
   static size_t printTo(const char *, Print *);
-
   static char *extractFrom(char *input, char **end);
 };
 }
diff --git a/include/ArduinoJson/JsonArray.hpp b/include/ArduinoJson/JsonArray.hpp
index 0d944ef6..ec371abc 100644
--- a/include/ArduinoJson/JsonArray.hpp
+++ b/include/ArduinoJson/JsonArray.hpp
@@ -13,6 +13,7 @@
 #include "JsonObject.hpp"
 
 namespace ArduinoJson {
+
 class JsonArray : public JsonPrintable {
   friend class JsonBuffer;
 
@@ -25,14 +26,15 @@ class JsonArray : public JsonPrintable {
 
   bool success() { return _buffer != NULL; }
 
-  value_type &operator[](int index) const;
-  value_type &add();
+  value_type &operator[](int index) const { return at(index); }
+  value_type &at(int index) const;
 
   template <typename T>
   void add(T value) {
     add().set(value);
   }
 
+  value_type &add();
   void add(double value, int decimals) { add().set(value, decimals); }
   void add(JsonArray &nestedArray) { add().set(nestedArray); }
   void add(JsonObject &nestedObject) { add().set(nestedObject); }
@@ -54,14 +56,21 @@ class JsonArray : public JsonPrintable {
   // constructor is private: instance must be created via a JsonBuffer
   JsonArray(JsonBuffer *buffer) : _buffer(buffer), _firstNode(NULL) {}
 
-  JsonArray(const JsonArray &);  // copy is forbidden, use a reference instead
-  JsonArray &operator=(
-      const JsonArray &);  // copy is forbidden, use a reference instead
+  // copy is forbidden, use a reference instead
+  JsonArray(const JsonArray &);
+  JsonArray &operator=(const JsonArray &);
 
+  Internals::JsonArrayNode *createNode();
   inline void addNode(Internals::JsonArrayNode *node);
 
   JsonBuffer *_buffer;
   Internals::JsonArrayNode *_firstNode;
   static JsonArray _invalid;
 };
+
+bool operator==(const JsonArray &left, const JsonArray &right) {
+  // two JsonArray are equal if they are the same instance
+  // (we don't compare the content)
+  return &left == &right;
+}
 }
diff --git a/include/ArduinoJson/JsonArrayConstIterator.hpp b/include/ArduinoJson/JsonArrayConstIterator.hpp
index 4703987c..863bc83e 100644
--- a/include/ArduinoJson/JsonArrayConstIterator.hpp
+++ b/include/ArduinoJson/JsonArrayConstIterator.hpp
@@ -34,4 +34,4 @@ class JsonArrayConstIterator {
  private:
   Internals::JsonArrayNode *_node;
 };
-}
\ No newline at end of file
+}
diff --git a/include/ArduinoJson/JsonBuffer.hpp b/include/ArduinoJson/JsonBuffer.hpp
index ca323c37..b16a321d 100644
--- a/include/ArduinoJson/JsonBuffer.hpp
+++ b/include/ArduinoJson/JsonBuffer.hpp
@@ -6,8 +6,6 @@
 
 #pragma once
 
-#include <new>
-
 #include "ForwardDeclarations.hpp"
 #include "JsonValue.hpp"
 
diff --git a/include/ArduinoJson/JsonObject.hpp b/include/ArduinoJson/JsonObject.hpp
index cff469e3..52e39ca3 100644
--- a/include/ArduinoJson/JsonObject.hpp
+++ b/include/ArduinoJson/JsonObject.hpp
@@ -13,6 +13,7 @@
 #include "JsonArray.hpp"
 
 namespace ArduinoJson {
+
 class JsonObject : public JsonPrintable {
   friend class JsonBuffer;
 
@@ -22,16 +23,18 @@ class JsonObject : public JsonPrintable {
   typedef JsonObjectIterator iterator;
   typedef JsonObjectConstIterator const_iterator;
 
+  bool success() const { return _buffer != NULL; }
   int size() const;
 
-  JsonValue &operator[](key_type key);
+  JsonValue &at(key_type key);
+  JsonValue &operator[](key_type key) { return at(key); }
+
   void remove(key_type key);
 
   template <typename T>
   void add(key_type key, T value) {
     add(key).set(value);
   }
-
   void add(key_type key, JsonArray &array) { add(key).set(array); }
   void add(key_type key, JsonObject &object) { add(key).set(object); }
 
@@ -57,6 +60,7 @@ class JsonObject : public JsonPrintable {
       const JsonObject &);  // copy is forbidden, use a reference instead
 
   JsonValue &add(key_type key) { return (*this)[key]; }
+  Internals::JsonObjectNode *createNode(key_type key);
   void addNode(Internals::JsonObjectNode *nodeToAdd);
   void removeNode(Internals::JsonObjectNode *nodeToRemove);
 
@@ -67,4 +71,10 @@ class JsonObject : public JsonPrintable {
   Internals::JsonObjectNode *_firstNode;
   static JsonObject _invalid;
 };
+
+bool operator==(const JsonObject &left, const JsonObject &right) {
+  // two JsonObject are equal if they are the same instance
+  // (we don't compare the content)
+  return &left == &right;
+}
 }
diff --git a/include/ArduinoJson/JsonPair.hpp b/include/ArduinoJson/JsonPair.hpp
index 774fb84a..d540ad30 100644
--- a/include/ArduinoJson/JsonPair.hpp
+++ b/include/ArduinoJson/JsonPair.hpp
@@ -10,6 +10,7 @@
 #include "Internals/JsonObjectNode.hpp"
 
 namespace ArduinoJson {
+
 struct JsonPair {
   JsonPair(const char* k) : key(k) {}
 
diff --git a/include/ArduinoJson/JsonValue.hpp b/include/ArduinoJson/JsonValue.hpp
index df90a9be..594c48ce 100644
--- a/include/ArduinoJson/JsonValue.hpp
+++ b/include/ArduinoJson/JsonValue.hpp
@@ -13,7 +13,6 @@
 #include "Internals/JsonValueType.hpp"
 
 namespace ArduinoJson {
-
 class JsonValue {
  public:
   JsonValue() : _type(Internals::JSON_UNDEFINED) {}
@@ -64,7 +63,10 @@ class JsonValue {
   void writeTo(Internals::JsonWriter &writer) const;
 
  private:
+  JsonValue(Internals::JsonValueType type) : _type(type) {}
+
   Internals::JsonValueType _type;
   Internals::JsonValueContent _content;
   static JsonValue _invalid;
 };
+}
diff --git a/src/JsonArray.cpp b/src/JsonArray.cpp
index 72972e30..0233df70 100644
--- a/src/JsonArray.cpp
+++ b/src/JsonArray.cpp
@@ -6,6 +6,8 @@
 
 #include "ArduinoJson/JsonArray.hpp"
 
+#include <new>  // required for placement new
+
 #include "ArduinoJson/JsonBuffer.hpp"
 #include "ArduinoJson/JsonObject.hpp"
 #include "ArduinoJson/Internals/JsonWriter.hpp"
@@ -13,20 +15,22 @@
 using namespace ArduinoJson;
 using namespace ArduinoJson::Internals;
 
+JsonArray JsonArray::_invalid(NULL);
+
 int JsonArray::size() const {
   int nodeCount = 0;
   for (JsonArrayNode *node = _firstNode; node; node = node->next) nodeCount++;
   return nodeCount;
 }
 
-JsonValue &JsonArray::operator[](int index) const {
+JsonValue &JsonArray::at(int index) const {
   JsonArrayNode *node = _firstNode;
   while (node && index--) node = node->next;
   return node ? node->value : JsonValue::invalid();
 }
 
 JsonValue &JsonArray::add() {
-  JsonArrayNode *node = JsonArrayNode::createFrom(_buffer);
+  JsonArrayNode *node = createNode();
   if (!node) return JsonValue::invalid();
 
   addNode(node);
@@ -34,6 +38,12 @@ JsonValue &JsonArray::add() {
   return node->value;
 }
 
+JsonArrayNode *JsonArray::createNode() {
+  if (_buffer) return NULL;
+  void *ptr = _buffer->alloc(sizeof(JsonArrayNode));
+  return ptr ? new (ptr) JsonArrayNode() : NULL;
+}
+
 void JsonArray::addNode(JsonArrayNode *newNode) {
   if (_firstNode) {
     JsonArrayNode *lastNode = _firstNode;
diff --git a/src/JsonBuffer.cpp b/src/JsonBuffer.cpp
index fa59ce20..c09a8f96 100644
--- a/src/JsonBuffer.cpp
+++ b/src/JsonBuffer.cpp
@@ -6,6 +6,8 @@
 
 #include "ArduinoJson/JsonBuffer.hpp"
 
+#include <new>  // required for the placement new
+
 #include "ArduinoJson/JsonArray.hpp"
 #include "ArduinoJson/JsonObject.hpp"
 #include "ArduinoJson/JsonValue.hpp"
diff --git a/src/JsonObject.cpp b/src/JsonObject.cpp
index 277920fe..27438d31 100644
--- a/src/JsonObject.cpp
+++ b/src/JsonObject.cpp
@@ -6,6 +6,7 @@
 
 #include "ArduinoJson/JsonObject.hpp"
 
+#include <new>       // required for placement new
 #include <string.h>  // for strcmp
 
 #include "ArduinoJson/JsonBuffer.hpp"
@@ -17,13 +18,15 @@
 using namespace ArduinoJson;
 using namespace ArduinoJson::Internals;
 
+JsonObject JsonObject::_invalid(NULL);
+
 int JsonObject::size() const {
   int nodeCount = 0;
   for (JsonObjectNode *node = _firstNode; node; node = node->next) nodeCount++;
   return nodeCount;
 }
 
-JsonValue &JsonObject::operator[](const char *key) {
+JsonValue &JsonObject::at(const char *key) {
   JsonObjectNode *node = getOrCreateNodeAt(key);
   return node ? node->pair.value : JsonValue::invalid();
 }
@@ -55,13 +58,19 @@ JsonObjectNode *JsonObject::getOrCreateNodeAt(const char *key) {
   JsonObjectNode *existingNode = getNodeAt(key);
   if (existingNode) return existingNode;
 
-  JsonObjectNode *newNode = JsonObjectNode::createFrom(_buffer, key);
+  JsonObjectNode *newNode = createNode(key);
 
   if (newNode) addNode(newNode);
 
   return newNode;
 }
 
+JsonObjectNode *JsonObject::createNode(const char *key) {
+  if (!_buffer) return NULL;
+  void *ptr = _buffer->alloc(sizeof(JsonObjectNode));
+  return ptr ? new (ptr) JsonObjectNode(key) : NULL;
+}
+
 void JsonObject::addNode(JsonObjectNode *nodeToAdd) {
   if (!_firstNode) {
     _firstNode = nodeToAdd;
diff --git a/src/JsonValue.cpp b/src/JsonValue.cpp
index 06cb26b9..c0bdfc1a 100644
--- a/src/JsonValue.cpp
+++ b/src/JsonValue.cpp
@@ -12,6 +12,8 @@
 using namespace ArduinoJson;
 using namespace ArduinoJson::Internals;
 
+JsonValue JsonValue::_invalid(JSON_INVALID);
+
 JsonValue::operator JsonArray &() const {
   return _type == JSON_ARRAY ? *_content.asArray : JsonArray::invalid();
 }
diff --git a/test/JsonObject_PrettyPrintTo_Tests.cpp b/test/JsonObject_PrettyPrintTo_Tests.cpp
index d356f36c..0ed70055 100644
--- a/test/JsonObject_PrettyPrintTo_Tests.cpp
+++ b/test/JsonObject_PrettyPrintTo_Tests.cpp
@@ -13,11 +13,12 @@
 using namespace ArduinoJson;
 
 class JsonObject_PrettyPrintTo_Tests : public testing::Test {
- protected:
-  JsonObject object;
-  StaticJsonBuffer<30> json;
+ public:
+  JsonObject_PrettyPrintTo_Tests() : object(json.createObject()) {}
 
-  virtual void SetUp() { object = json.createObject(); }
+ protected:
+  JsonObject &object;
+  StaticJsonBuffer<30> json;
 
   void outputMustBe(const char *expected) {
     size_t n = object.prettyPrintTo(buffer, sizeof(buffer));
@@ -63,10 +64,10 @@ TEST_F(JsonObject_PrettyPrintTo_Tests, EmptyNestedContainers) {
 }
 
 TEST_F(JsonObject_PrettyPrintTo_Tests, NestedContainers) {
-  JsonObject nested1 = object.createNestedObject("key1");
+  JsonObject &nested1 = object.createNestedObject("key1");
   nested1["a"] = 1;
 
-  JsonArray nested2 = object.createNestedArray("key2");
+  JsonArray &nested2 = object.createNestedArray("key2");
   nested2.add(2);
 
   outputMustBe(
diff --git a/test/JsonObject_Serialization_Tests.cpp b/test/JsonObject_Serialization_Tests.cpp
index 1ea4b0d9..ee415221 100644
--- a/test/JsonObject_Serialization_Tests.cpp
+++ b/test/JsonObject_Serialization_Tests.cpp
@@ -13,9 +13,10 @@
 using namespace ArduinoJson;
 
 class JsonObject_Serialization_Tests : public testing::Test {
- protected:
-  virtual void SetUp() { object = json.createObject(); }
+ public:
+  JsonObject_Serialization_Tests() : object(json.createObject()) {}
 
+ protected:
   void outputMustBe(const char *expected) {
     char actual[256];
     int result = object.printTo(actual, sizeof(actual));
@@ -24,7 +25,7 @@ class JsonObject_Serialization_Tests : public testing::Test {
     EXPECT_EQ(strlen(expected), result);
   }
 
-  JsonObject object;
+  JsonObject &object;
   StaticJsonBuffer<5> json;
 };
 
@@ -113,7 +114,7 @@ TEST_F(JsonObject_Serialization_Tests, OneFalse) {
 }
 
 TEST_F(JsonObject_Serialization_Tests, OneEmptyNestedArrayViaProxy) {
-  JsonArray nestedArray = json.createArray();
+  JsonArray &nestedArray = json.createArray();
 
   object["key"] = nestedArray;
 
@@ -121,7 +122,7 @@ TEST_F(JsonObject_Serialization_Tests, OneEmptyNestedArrayViaProxy) {
 }
 
 TEST_F(JsonObject_Serialization_Tests, OneEmptyNestedObjectViaProxy) {
-  JsonObject nestedArray = json.createObject();
+  JsonObject &nestedArray = json.createObject();
 
   object["key"] = nestedArray;
 
diff --git a/test/JsonParser_Array_Tests.cpp b/test/JsonParser_Array_Tests.cpp
index c5891211..6b1b33a1 100644
--- a/test/JsonParser_Array_Tests.cpp
+++ b/test/JsonParser_Array_Tests.cpp
@@ -15,17 +15,17 @@ class JsonParser_Array_Tests : public testing::Test {
  protected:
   void whenInputIs(const char *json) {
     strcpy(_jsonString, json);
-    _array = _jsonBuffer.parseArray(_jsonString);
+    _array = &_jsonBuffer.parseArray(_jsonString);
   }
 
-  void parseMustSucceed() { EXPECT_TRUE(_array.success()); }
+  void parseMustSucceed() { EXPECT_TRUE(_array->success()); }
 
   void parseMustFail() {
-    EXPECT_FALSE(_array.success());
-    EXPECT_EQ(0, _array.size());
+    EXPECT_FALSE(_array->success());
+    EXPECT_EQ(0, _array->size());
   }
 
-  void sizeMustBe(int expected) { EXPECT_EQ(expected, _array.size()); }
+  void sizeMustBe(int expected) { EXPECT_EQ(expected, _array->size()); }
 
   template <typename T>
   void firstElementMustBe(T expected) {
@@ -39,15 +39,15 @@ class JsonParser_Array_Tests : public testing::Test {
 
   template <typename T>
   void elementAtIndexMustBe(int index, T expected) {
-    EXPECT_EQ(expected, _array[index].as<T>());
+    EXPECT_EQ(expected, _array->at(index).as<T>());
   }
 
   void elementAtIndexMustBe(int index, const char *expected) {
-    EXPECT_STREQ(expected, _array[index].as<const char *>());
+    EXPECT_STREQ(expected, _array->at(index).as<const char *>());
   }
 
   StaticJsonBuffer<42> _jsonBuffer;
-  JsonArray _array;
+  JsonArray *_array;
   char _jsonString[256];
 };
 
diff --git a/test/JsonParser_Nested_Tests.cpp b/test/JsonParser_Nested_Tests.cpp
index cb5c8ca0..4d350448 100644
--- a/test/JsonParser_Nested_Tests.cpp
+++ b/test/JsonParser_Nested_Tests.cpp
@@ -15,9 +15,9 @@ TEST(JsonParser_Nested_Tests, ArrayNestedInObject) {
   StaticJsonBuffer<42> jsonBuffer;
   char jsonString[] = " { \"ab\" : [ 1 , 2 ] , \"cd\" : [ 3 , 4 ] } ";
 
-  JsonObject object = jsonBuffer.parseObject(jsonString);
-  JsonArray array1 = object["ab"];
-  JsonArray array2 = object["cd"];
+  JsonObject &object = jsonBuffer.parseObject(jsonString);
+  JsonArray &array1 = object["ab"];
+  JsonArray &array2 = object["cd"];
 
   ASSERT_TRUE(object.success());
 
@@ -39,9 +39,9 @@ TEST(JsonParser_Nested_Tests, ObjectNestedInArray) {
   char jsonString[] =
       " [ { \"a\" : 1 , \"b\" : 2 } , { \"c\" : 3 , \"d\" : 4 } ] ";
 
-  JsonArray array = jsonBuffer.parseArray(jsonString);
-  JsonObject object1 = array[0];
-  JsonObject object2 = array[1];
+  JsonArray &array = jsonBuffer.parseArray(jsonString);
+  JsonObject &object1 = array[0];
+  JsonObject &object2 = array[1];
 
   ASSERT_TRUE(array.success());
 
diff --git a/test/JsonParser_Object_Tests.cpp b/test/JsonParser_Object_Tests.cpp
index 6f3ad588..fd8d3607 100644
--- a/test/JsonParser_Object_Tests.cpp
+++ b/test/JsonParser_Object_Tests.cpp
@@ -15,27 +15,27 @@ class JsonParser_Object_Test : public testing::Test {
  protected:
   void whenInputIs(const char *jsonString) {
     strcpy(_jsonString, jsonString);
-    _object = _jsonBuffer.parseObject(_jsonString);
+    _object = &_jsonBuffer.parseObject(_jsonString);
   }
 
-  void parseMustSucceed() { EXPECT_TRUE(_object.success()); }
+  void parseMustSucceed() { EXPECT_TRUE(_object->success()); }
 
-  void parseMustFail() { EXPECT_FALSE(_object.success()); }
+  void parseMustFail() { EXPECT_FALSE(_object->success()); }
 
-  void sizeMustBe(int expected) { EXPECT_EQ(expected, _object.size()); }
+  void sizeMustBe(int expected) { EXPECT_EQ(expected, _object->size()); }
 
   void keyMustHaveValue(const char *key, const char *expected) {
-    EXPECT_STREQ(expected, _object[key].as<const char *>());
+    EXPECT_STREQ(expected, _object->at(key).as<const char *>());
   }
 
   template <typename T>
   void keyMustHaveValue(const char *key, T expected) {
-    EXPECT_EQ(expected, _object[key].as<T>());
+    EXPECT_EQ(expected, _object->at(key).as<T>());
   }
 
  private:
   StaticJsonBuffer<10> _jsonBuffer;
-  JsonObject _object;
+  JsonObject *_object;
   char _jsonString[256];
 };
 
diff --git a/test/JsonValueTests.cpp b/test/JsonValueTests.cpp
index 78c46875..6b0c754e 100644
--- a/test/JsonValueTests.cpp
+++ b/test/JsonValueTests.cpp
@@ -15,11 +15,6 @@ using namespace ArduinoJson;
 
 class JsonValueTests : public ::testing::Test {
  protected:
-  virtual void SetUp() {
-    jsonValue1 = json.createValue();
-    jsonValue2 = json.createValue();
-  }
-
   StaticJsonBuffer<42> json;
   JsonValue jsonValue1;
   JsonValue jsonValue2;
@@ -54,11 +49,11 @@ TEST_F(JsonValueTests, CanStoreString) {
 }
 
 TEST_F(JsonValueTests, CanStoreObject) {
-  JsonObject innerObject1 = json.createObject();
+  JsonObject &innerObject1 = json.createObject();
 
   jsonValue1 = innerObject1;
 
-  EXPECT_EQ(innerObject1, jsonValue1.as<JsonObject>());
+  EXPECT_EQ(innerObject1, jsonValue1.asObject());
 }
 
 TEST_F(JsonValueTests, IntegersAreCopiedByValue) {
@@ -94,21 +89,21 @@ TEST_F(JsonValueTests, StringsAreCopiedByValue) {
 }
 
 TEST_F(JsonValueTests, ObjectsAreCopiedByReference) {
-  JsonObject object = json.createObject();
+  JsonObject &object = json.createObject();
 
   jsonValue1 = object;
 
   object["hello"] = "world";
 
-  EXPECT_EQ(1, jsonValue1.as<JsonObject>().size());
+  EXPECT_EQ(1, jsonValue1.asObject().size());
 }
 
 TEST_F(JsonValueTests, ArraysAreCopiedByReference) {
-  JsonArray array = json.createArray();
+  JsonArray &array = json.createArray();
 
   jsonValue1 = array;
 
   array.add("world");
 
-  EXPECT_EQ(1, jsonValue1.as<JsonArray>().size());
+  EXPECT_EQ(1, jsonValue1.asArray().size());
 }
diff --git a/test/StaticJsonBufferTests.cpp b/test/StaticJsonBufferTests.cpp
index b3d92271..b3260a41 100644
--- a/test/StaticJsonBufferTests.cpp
+++ b/test/StaticJsonBufferTests.cpp
@@ -46,14 +46,14 @@ TEST(StaticJsonBuffer,
      WhenCreateObjectIsCalled_ThenAnEmptyJsonObjectIsReturned) {
   StaticJsonBuffer<42> json;
 
-  JsonObject obj = json.createObject();
+  JsonObject &obj = json.createObject();
   EXPECT_EQ(0, obj.size());
 }
 
 TEST(StaticJsonBuffer,
      GivenAJsonObject_WhenValuesAreAdded_ThenSizeIsIncreasedByTwo) {
   StaticJsonBuffer<42> json;
-  JsonObject obj = json.createObject();
+  JsonObject &obj = json.createObject();
 
   obj["hello"];
   EXPECT_EQ(3, json.size());
@@ -66,7 +66,7 @@ TEST(
     StaticJsonBuffer,
     GivenAJsonObject_WhenSameValuesAreAddedTwice_ThenSizeIsOnlyIncreasedByTwo) {
   StaticJsonBuffer<42> json;
-  JsonObject obj = json.createObject();
+  JsonObject &obj = json.createObject();
 
   obj["hello"];
   EXPECT_EQ(3, json.size());