diff --git a/arangod/Aql/AqlValue.cpp b/arangod/Aql/AqlValue.cpp
index 41c0c1eeb7..07d51f6c61 100644
--- a/arangod/Aql/AqlValue.cpp
+++ b/arangod/Aql/AqlValue.cpp
@@ -28,12 +28,15 @@
 #include "Utils/AqlTransaction.h"
 #include "Utils/ShapedJsonTransformer.h"
 #include "V8/v8-conv.h"
+#include "V8/v8-vpack.h"
 #include "V8Server/v8-shape-conv.h"
 #include "V8Server/v8-wrapshapedjson.h"
 #include "VocBase/document-collection.h"
 #include "VocBase/VocShaper.h"
 
 #include <velocypack/Buffer.h>
+#include <velocypack/Iterator.h>
+#include <velocypack/Slice.h>
 #include <velocypack/velocypack-aliases.h>
 
 using namespace arangodb::aql;
@@ -732,74 +735,147 @@ Json AqlValue::toJson(arangodb::AqlTransaction* trx,
 }
 
 ////////////////////////////////////////////////////////////////////////////////
-/// @brief Constructor
+/// @brief constructor
 ////////////////////////////////////////////////////////////////////////////////
   
 AqlValue$::AqlValue$() {
-  VPackBuilder builder;
-  memcpy(_data.internal, builder.slice().begin(), builder.slice().byteSize());
-  _data.internal[15] = AqlValueType::INTERNAL; 
+  invalidate(*this);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
-/// @brief Constructor
+/// @brief constructor
 ////////////////////////////////////////////////////////////////////////////////
 
 AqlValue$::AqlValue$(VPackBuilder const& data) {
   TRI_ASSERT(data.isClosed());
-  VPackValueLength l = data.size();
-  if (l < 16) {
+  VPackValueLength length = data.size();
+  if (length < 16) {
     // Use internal
-    memcpy(_data.internal, data.data(), l);
-    _data.internal[15] = AqlValueType::INTERNAL; 
+    memcpy(_data.internal, data.data(), length);
+    setType(AqlValueType::INTERNAL);
   } else {
     // Use external
-    _data.external = new VPackBuffer<uint8_t>(l);
-    memcpy(_data.external->data(), data.data(), l);
-    _data.internal[15] = AqlValueType::EXTERNAL; 
+    _data.external = new VPackBuffer<uint8_t>(length);
+    memcpy(_data.external->data(), data.data(), length);
+    setType(AqlValueType::EXTERNAL);
   }
 }
 
 ////////////////////////////////////////////////////////////////////////////////
-/// @brief Constructor
+/// @brief constructor
 ////////////////////////////////////////////////////////////////////////////////
 
 AqlValue$::AqlValue$(VPackBuilder const* data) : AqlValue$(*data) {}
 
 ////////////////////////////////////////////////////////////////////////////////
-/// @brief Constructor
+/// @brief constructor
 ////////////////////////////////////////////////////////////////////////////////
 
 AqlValue$::AqlValue$(VPackSlice const& data) {
-  VPackValueLength l = data.byteSize();
-  if (l < 16) {
+  VPackValueLength length = data.byteSize();
+  if (length < 16) {
     // Use internal
-    memcpy(_data.internal, data.start(), l);
-    _data.internal[15] = AqlValueType::INTERNAL; 
+    memcpy(_data.internal, data.begin(), length);
+    setType(AqlValueType::INTERNAL);
   } else {
     // Use external
-    _data.external = new VPackBuffer<uint8_t>(l);
-    memcpy(_data.external->data(), data.start(), l);
-    _data.internal[15] = AqlValueType::EXTERNAL; 
+    _data.external = new VPackBuffer<uint8_t>(length);
+    memcpy(_data.external->data(), data.begin(), length);
+    setType(AqlValueType::EXTERNAL);
   }
 }
 
 ////////////////////////////////////////////////////////////////////////////////
-/// @brief Copy Constructor.
+/// @brief constructor
+////////////////////////////////////////////////////////////////////////////////
+
+AqlValue$::AqlValue$(VPackSlice const& data, AqlValueType type) {
+  if (type == AqlValueType::REFERENCE ||
+      type == AqlValueType::REFERENCE_STICKY) {
+    // simply copy the slice
+    _data.reference = data.begin();
+    setType(type);
+    return;
+  }
+
+  // everything else as usual
+  VPackValueLength length = data.byteSize();
+  if (length < 16) {
+    // Use internal
+    memcpy(_data.internal, data.begin(), length);
+    setType(AqlValueType::INTERNAL);
+  } else {
+    // Use external
+    _data.external = new VPackBuffer<uint8_t>(length);
+    memcpy(_data.external->data(), data.begin(), length);
+    setType(AqlValueType::EXTERNAL);
+  }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief constructor with range value
+////////////////////////////////////////////////////////////////////////////////
+  
+AqlValue$::AqlValue$(int64_t low, int64_t high) {
+  Range* range = new Range(low, high);
+
+  _data.internal[0] = 0xf4; // custom type for range
+  _data.internal[1] = sizeof(Range*);
+  memcpy(&_data.internal[2], &range, sizeof(Range*));
+  setType(AqlValueType::RANGE);
+}
+   
+AqlValue$::AqlValue$(bool value) 
+    : AqlValue$(value ? arangodb::basics::VelocyPackHelper::TrueValue() : 
+       arangodb::basics::VelocyPackHelper::FalseValue()) {
+}
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief destructor
+////////////////////////////////////////////////////////////////////////////////
+  
+AqlValue$::~AqlValue$() {
+  destroy();
+}
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief copy
 ////////////////////////////////////////////////////////////////////////////////
 
 AqlValue$::AqlValue$(AqlValue$ const& other) {
-  VPackSlice s = other.slice();
-  VPackValueLength length = s.byteSize();
-  if (other.type()) {
-    // Isse external
-    _data.external = new VPackBuffer<uint8_t>(length);
-    memcpy(_data.external->data(), other._data.external->data(), length);
-    _data.internal[15] = AqlValueType::EXTERNAL; 
-  } else {
-    memcpy(_data.internal, other._data.internal, length);
-    _data.internal[15] = AqlValueType::INTERNAL; 
+  copy(other);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief copy
+////////////////////////////////////////////////////////////////////////////////
+
+AqlValue$& AqlValue$::operator=(AqlValue$ const& other) {
+  if (this != &other) {
+    destroy();
+    copy(other);
   }
+  return *this;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief move
+////////////////////////////////////////////////////////////////////////////////
+
+AqlValue$::AqlValue$(AqlValue$&& other) {
+  move(other);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief move
+////////////////////////////////////////////////////////////////////////////////
+
+AqlValue$& AqlValue$::operator=(AqlValue$&& other) {
+  if (this != &other) {
+    destroy();
+    move(other);
+  }
+  return *this;
 }
 
 // Temporary constructor to transform an old AqlValue to a new VPackBased
@@ -849,14 +925,12 @@ AqlValue$::AqlValue$(AqlValue const& other, arangodb::AqlTransaction* trx,
     case AqlValue::RANGE: {
       // TODO Has to be replaced by VPackCustom Type
       TRI_ASSERT(other._range != nullptr);
-      try {
-        VPackArrayBuilder b(&builder);
-        size_t const n = other._range->size();
-        for (size_t i = 0; i < n; ++i) {
-          builder.add(VPackValue(other._range->at(i)));
-        }
-      } catch (...) {
-      }
+      Range* range = new Range(other._range->_low, other._range->_high);
+
+      _data.internal[0] = 0xf4; // custom type for range
+      _data.internal[1] = sizeof(Range*);
+      memcpy(&_data.internal[2], &range, sizeof(Range*));
+      _data.internal[15] = AqlValueType::RANGE; 
       break;
     }
     case AqlValue::EMPTY: {
@@ -864,60 +938,227 @@ AqlValue$::AqlValue$(AqlValue const& other, arangodb::AqlTransaction* trx,
       break;
     }
     default: {
-        TRI_ASSERT(false);
-        THROW_ARANGO_EXCEPTION(TRI_ERROR_INTERNAL);
-      }
+      TRI_ASSERT(false);
+      THROW_ARANGO_EXCEPTION(TRI_ERROR_INTERNAL);
+    }
   }
   VPackValueLength length = builder.size();
   if (length < 16) {
     // Small enough for local
     // copy memory from the builder into the internal data.
     memcpy(_data.internal, builder.data(), length);
-    _data.internal[15] = AqlValueType::INTERNAL; 
+    setType(AqlValueType::INTERNAL);
   } else {
     // We need a large external buffer
     // TODO: Replace by SlimBuffer
     _data.external = new VPackBuffer<uint8_t>(length);
     memcpy(_data.external->data(), builder.data(), length);
-    _data.internal[15] = AqlValueType::EXTERNAL; 
+    setType(AqlValueType::EXTERNAL);
   }
 }
 
-AqlValue$::AqlValueType AqlValue$::type() const {
-  return static_cast<AqlValueType>(_data.internal[15]);
+//////////////////////////////////////////////////////////////////////////////
+/// @brief return a slice for the contained value
+//////////////////////////////////////////////////////////////////////////////
+
+VPackSlice AqlValue$::slice() const {
+  switch (type()) {
+    case EXTERNAL:
+      return VPackSlice(_data.external->data());
+    case REFERENCE:
+    case REFERENCE_STICKY:
+      return VPackSlice(_data.reference);
+    case INTERNAL:
+    case RANGE: 
+      return VPackSlice(_data.internal);
+  }
+  return VPackSlice(); // we should not get here
+}
+
+//////////////////////////////////////////////////////////////////////////////
+/// @brief whether or not the value is empty / none
+//////////////////////////////////////////////////////////////////////////////
+ 
+bool AqlValue$::isNone() const {
+  return slice().isNone();
+}
+
+//////////////////////////////////////////////////////////////////////////////
+/// @brief whether or not the value is a number
+//////////////////////////////////////////////////////////////////////////////
+ 
+bool AqlValue$::isNumber() const {
+  if (type() == RANGE) {
+    return false;
+  }
+  return slice().isNumber();
+}
+
+//////////////////////////////////////////////////////////////////////////////
+/// @brief whether or not the value is an object
+//////////////////////////////////////////////////////////////////////////////
+ 
+bool AqlValue$::isObject() const {
+  if (type() == RANGE) {
+    // special handling for ranges
+    return true;
+  }
+  // all other cases
+  return slice().isObject();
+}
+
+//////////////////////////////////////////////////////////////////////////////
+/// @brief whether or not the value is an array (note: this treats ranges
+/// as arrays, too!)
+//////////////////////////////////////////////////////////////////////////////
+ 
+bool AqlValue$::isArray() const {
+  if (type() == RANGE) {
+    // special handling for ranges
+    return true;
+  }
+  // all other cases
+  return slice().isArray();
 }
   
+//////////////////////////////////////////////////////////////////////////////
+/// @brief get the (array) length (note: this treats ranges as arrays, too!)
+//////////////////////////////////////////////////////////////////////////////
+
+size_t AqlValue$::length() const {
+  if (type() == RANGE) {
+    // special handling for ranges
+    return range()->size();
+  }
+  // all other cases
+  VPackSlice const s = slice();
+  if (s.isArray()) {
+    return s.length();
+  }
+  return 0;
+}
+  
+//////////////////////////////////////////////////////////////////////////////
+/// @brief get the (array) element at position 
+//////////////////////////////////////////////////////////////////////////////
+
+AqlValue$ AqlValue$::at(int64_t position) const {
+  if (type() == RANGE) {
+    // special handling for ranges
+    Range* r = range();
+    size_t const n = r->size();
+
+    if (position < 0) {
+      // a negative position is allowed
+      position = static_cast<int64_t>(n) + position;
+    }
+
+    if (position >= 0 && position < static_cast<int64_t>(n)) {
+      // only look up the value if it is within array bounds
+      VPackBuilder builder;
+      builder.add(VPackValue(r->at(static_cast<size_t>(position))));
+      return AqlValue$(builder);
+    }
+    // fall-through intentional
+  }
+  else {
+    VPackSlice const s = slice();
+    if (s.isArray()) {
+      size_t const n = static_cast<size_t>(s.length());
+      if (position < 0) {
+        // a negative position is allowed
+        position = static_cast<int64_t>(n) + position;
+      }
+
+      if (position >= 0 && position < static_cast<int64_t>(n)) {
+        // only look up the value if it is within array bounds
+        if (type() == AqlValueType::REFERENCE_STICKY) {
+          return AqlValue$(s.at(position), AqlValueType::REFERENCE_STICKY);
+        }
+        return AqlValue$(s.at(position));
+      }
+    }
+  }
+
+  // default is to return null
+  return AqlValue$(arangodb::basics::VelocyPackHelper::NullValue(), REFERENCE_STICKY);
+}
+  
+//////////////////////////////////////////////////////////////////////////////
+/// @brief get the (object) element by name
+//////////////////////////////////////////////////////////////////////////////
+  
+AqlValue$ AqlValue$::get(std::string const& name) const {
+  VPackSlice const s = slice();
+  if (s.isObject()) {
+    VPackSlice const value = s.get(name);
+    if (!value.isNone()) {
+      if (type() == AqlValueType::REFERENCE_STICKY) {
+        return AqlValue$(value, AqlValueType::REFERENCE_STICKY);
+      }
+      return AqlValue$(value);
+    }
+  }
+  
+  // default is to return null
+  return AqlValue$(arangodb::basics::VelocyPackHelper::NullValue(), REFERENCE_STICKY);
+}
+
+//////////////////////////////////////////////////////////////////////////////
+/// @brief get the (object) element(s) by name
+//////////////////////////////////////////////////////////////////////////////
+  
+AqlValue$ AqlValue$::get(std::vector<char const*> const& names) const {
+  VPackSlice const s = slice();
+  if (s.isObject()) {
+    VPackSlice const value = s.get(names);
+    if (!value.isNone()) {
+      if (type() == AqlValueType::REFERENCE_STICKY) {
+        return AqlValue$(value, AqlValueType::REFERENCE_STICKY);
+      }
+      return AqlValue$(value);
+    }
+  }
+  
+  // default is to return null
+  return AqlValue$(arangodb::basics::VelocyPackHelper::NullValue(), REFERENCE_STICKY);
+}
+
 //////////////////////////////////////////////////////////////////////////////
 /// @brief get the numeric value of an AqlValue
 //////////////////////////////////////////////////////////////////////////////
  
 double AqlValue$::toDouble() const {
-  if (slice().isCustom()) {
-#warning FIX custom      
-    // range. TODO
-    //size_t rangeSize = _range->size();
-    //if (rangeSize == 1) {
-    //  return _range->at(0);
-    //}
+  if (type() == RANGE) {
+    // special handling for ranges
+    Range* r = range();
+    size_t rangeSize = r->size();
+  
+    if (rangeSize == 1) {
+      return static_cast<double>(r->at(0));
+    }
     return 0.0;
   }
-  if (slice().isBoolean()) {
-    return slice().getBoolean() ? 1.0 : 0.0;
+
+  VPackSlice const s = slice();
+
+  if (s.isBoolean()) {
+    return s.getBoolean() ? 1.0 : 0.0;
   }
-  if (slice().isNumber()) {
-    return slice().getNumber<double>();
+  if (s.isNumber()) {
+    return s.getNumber<double>();
   }
-  if (slice().isString()) {
+  if (s.isString()) {
     try {
-      return std::stod(slice().copyString());
+      return std::stod(s.copyString());
     } catch (...) {
       // conversion failed
     }
     return 0.0;
   }
-  if (slice().isArray()) {
-    if (slice().length() == 1) {
-      AqlValue$ tmp(slice().at(0));
+  if (s.isArray()) {
+    if (s.length() == 1) {
+      AqlValue$ tmp(s.at(0));
       return tmp.toDouble();
     }
     return 0.0;
@@ -931,32 +1172,36 @@ double AqlValue$::toDouble() const {
 //////////////////////////////////////////////////////////////////////////////
 
 int64_t AqlValue$::toInt64() const {
-  if (slice().isCustom()) {
-#warning FIX custom      
-    // range. TODO
-    //size_t rangeSize = _range->size();
-    //if (rangeSize == 1) {
-    //  return _range->at(0);
-    //}
-    return 0;
+  if (type() == RANGE) {
+    // special handling for ranges
+    Range* r = range();
+    size_t rangeSize = r->size();
+  
+    if (rangeSize == 1) {
+      return static_cast<int64_t>(r->at(0));
+    }
+    return 0.0;
   }
-  if (slice().isBoolean()) {
-    return slice().getBoolean() ? 1 : 0;
+  
+  VPackSlice const s = slice();
+  
+  if (s.isBoolean()) {
+    return s.getBoolean() ? 1 : 0;
   }
-  if (slice().isNumber()) {
-    return slice().getNumber<int64_t>();
+  if (s.isNumber()) {
+    return s.getNumber<int64_t>();
   }
-  if (slice().isString()) {
+  if (s.isString()) {
     try {
-      return static_cast<int64_t>(std::stoll(slice().copyString()));
+      return static_cast<int64_t>(std::stoll(s.copyString()));
     } catch (...) {
       // conversion failed
     }
     return 0;
   }
-  if (slice().isArray()) {
-    if (slice().length() == 1) {
-      AqlValue$ tmp(slice().at(0));
+  if (s.isArray()) {
+    if (s.length() == 1) {
+      AqlValue$ tmp(s.at(0));
       return tmp.toInt64();
     }
     return 0;
@@ -965,36 +1210,235 @@ int64_t AqlValue$::toInt64() const {
   return 0;
 }
 
+//////////////////////////////////////////////////////////////////////////////
+/// @brief whether or not the contained value evaluates to true
+//////////////////////////////////////////////////////////////////////////////
+
 bool AqlValue$::isTrue() const {
-  if (slice().isBoolean() && slice().getBoolean()) {
-    return true;
-  } 
-  if (slice().isNumber() && slice().getNumber<double>() != 0.0) {
-    return true;
-  } 
-  if (slice().isString() && !slice().copyString().empty()) {
-    return true;
-  } 
-  if (slice().isArray() || slice().isObject()) {
+  if (type() == RANGE) {
     return true;
   }
-  if (slice().isCustom()) {
-    // range
-    return true;
-  } 
+  VPackSlice const s = slice();
 
+  if (s.isBoolean()) {
+    return s.getBoolean();
+  } 
+  if (s.isNumber()) {
+    return (s.getNumber<double>() != 0.0);
+  } 
+  if (s.isString()) {
+    VPackValueLength length;
+    s.getString(length);
+    return length > 0;
+  } 
+  if (s.isArray() || s.isObject()) {
+    return true;
+  }
+
+  // all other cases, include Null and None
   return false;
 }
 
-VPackSlice AqlValue$::slice() const {
-  if (type()) {
-    // Use External
-    return VPackSlice(_data.external->data());
-  } else {
-    return VPackSlice(_data.internal);
+////////////////////////////////////////////////////////////////////////////////
+/// @brief construct a V8 value as input for the expression execution in V8
+/// only construct those attributes that are needed in the expression
+////////////////////////////////////////////////////////////////////////////////
+
+v8::Handle<v8::Value> AqlValue$::toV8Partial(
+    v8::Isolate* isolate, arangodb::AqlTransaction* trx,
+    std::unordered_set<std::string> const& attributes) const {
+  VPackSlice const s = slice();
+
+  if (isObject()) {
+    v8::Handle<v8::Object> result = v8::Object::New(isolate);
+
+    // only construct those attributes needed
+    size_t left = attributes.size();
+
+    // we can only have got here if we had attributes
+    TRI_ASSERT(left > 0);
+
+    // iterate over all the object's attributes
+    for (auto const& it : VPackObjectIterator(s)) {
+      // check if we need to render this attribute
+      auto it2 = attributes.find(it.key.copyString());
+
+      if (it2 == attributes.end()) {
+        // we can skip the attribute
+        continue;
+      }
+
+      // TODO: do we need a customTypeHandler here?
+      result->ForceSet(TRI_V8_STD_STRING((*it2)),
+                       TRI_VPackToV8(isolate, it.value));
+
+      if (--left == 0) {
+        // we have rendered all required attributes
+        break;
+      }
+    }
+
+    // return partial object
+    return result;
+  }
+
+  // fallback
+  // TODO: do we need a customTypeHandler here?
+  return TRI_VPackToV8(isolate, s);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief construct a V8 value as input for the expression execution in V8
+////////////////////////////////////////////////////////////////////////////////
+
+v8::Handle<v8::Value> AqlValue$::toV8(
+    v8::Isolate* isolate, arangodb::AqlTransaction* trx) const {
+  if (type() == RANGE) {
+    Range* r = range();
+    size_t const n = r->size();
+
+    v8::Handle<v8::Array> result =
+          v8::Array::New(isolate, static_cast<int>(n));
+
+    for (uint32_t i = 0; i < n; ++i) {
+      // is it safe to use a double here (precision loss)?
+      result->Set(i, v8::Number::New(isolate, 
+        static_cast<double>(r->at(static_cast<size_t>(i)))));
+    }
+
+    return result;
+  }
+
+  // all other types go here
+  return TRI_VPackToV8(isolate, slice());
+}
+
+//////////////////////////////////////////////////////////////////////////////
+/// @brief sets the value type
+//////////////////////////////////////////////////////////////////////////////
+
+void AqlValue$::setType(AqlValueType type) {
+  _data.internal[15] = type;
+}
+
+//////////////////////////////////////////////////////////////////////////////
+/// @brief helper function for copy construction/assignment
+//////////////////////////////////////////////////////////////////////////////
+
+void AqlValue$::copy(AqlValue$ const& other) {
+  setType(other.type());
+  VPackValueLength length = other.slice().byteSize();
+  switch (other.type()) {
+    case EXTERNAL: {
+      _data.external = new VPackBuffer<uint8_t>(length);
+      memcpy(_data.external->data(), other._data.external->data(), length);
+      break;
+    }
+    case REFERENCE: 
+    case REFERENCE_STICKY: {
+      _data.reference = other._data.reference;
+      break;
+    }
+    case INTERNAL: {
+      memcpy(_data.internal, other._data.internal, length);
+      break;
+    }
+    case RANGE: {
+      Range* range = new Range(other.range()->_low, other.range()->_high);
+
+      _data.internal[0] = 0xf4; // custom type for range
+      _data.internal[1] = sizeof(Range*);
+      memcpy(&_data.internal[2], &range, sizeof(Range*));
+      break; 
+    }
   }
 }
 
+//////////////////////////////////////////////////////////////////////////////
+/// @brief helper function for move construction/assignment
+//////////////////////////////////////////////////////////////////////////////
+
+void AqlValue$::move(AqlValue$& other) {
+  setType(other.type());
+  switch (other.type()) {
+    case EXTERNAL: {
+      // steal the other's external value
+      _data.external = other._data.external;
+
+      // overwrite the other's value
+      invalidate(other);
+      break;
+    }
+    case REFERENCE: 
+    case REFERENCE_STICKY: {
+      // reuse the other's external value
+      _data.reference = other._data.reference;
+      break;
+    }
+    case INTERNAL: {
+      VPackValueLength length = other.slice().byteSize();
+      memcpy(_data.internal, other._data.internal, length);
+      break;
+    }
+    case RANGE: {
+      // copy the range pointer over to us
+      VPackValueLength length = other.slice().byteSize();
+      memcpy(_data.internal, other._data.internal, length);
+      
+      // overwrite the other's value
+      invalidate(other);
+      break;
+    }
+  }
+}
+
+//////////////////////////////////////////////////////////////////////////////
+/// @brief destroy the value's internals
+//////////////////////////////////////////////////////////////////////////////
+
+void AqlValue$::destroy() {
+  switch (type()) {
+    case EXTERNAL: {
+      if (_data.external != nullptr) {
+        delete _data.external;
+      }
+      break;
+    }
+    case REFERENCE:
+    case REFERENCE_STICKY:
+    case INTERNAL: {
+      // NOTHING TO DO
+      break;
+    }
+    case RANGE: {
+      delete range();
+      break;
+    }
+  }
+}
+
+//////////////////////////////////////////////////////////////////////////////
+/// @brief invalidates/resets a value to None
+//////////////////////////////////////////////////////////////////////////////
+
+void AqlValue$::invalidate(AqlValue$& other) {
+  VPackSlice empty; // None slice
+  memcpy(other._data.internal, empty.begin(), empty.byteSize());
+  setType(AqlValueType::INTERNAL);
+}
+  
+//////////////////////////////////////////////////////////////////////////////
+/// @brief get pointer of the included Range object
+//////////////////////////////////////////////////////////////////////////////
+
+Range* AqlValue$::range() const {
+  TRI_ASSERT(type() == RANGE);
+  Range* range = nullptr;
+  memcpy(&range, &_data.internal[2], sizeof(Range*));
+  return range;
+}
+
+
 void AqlValue::toVelocyPack(arangodb::AqlTransaction* trx,
                             TRI_document_collection_t const* document,
                             VPackBuilder& builder) const {
diff --git a/arangod/Aql/AqlValue.h b/arangod/Aql/AqlValue.h
index 0dc61af117..5ccc85e1ab 100644
--- a/arangod/Aql/AqlValue.h
+++ b/arangod/Aql/AqlValue.h
@@ -365,68 +365,124 @@ struct AqlValue {
   AqlValueType _type;
 };
 
+// do not add virtual methods!
 struct AqlValue$ {
  public:
+
   //////////////////////////////////////////////////////////////////////////////
   /// @brief AqlValueType, indicates what sort of value we have
   //////////////////////////////////////////////////////////////////////////////
 
-  enum AqlValueType { INTERNAL, EXTERNAL };
+  enum AqlValueType : uint8_t { INTERNAL, EXTERNAL, REFERENCE, REFERENCE_STICKY, RANGE };
 
   //////////////////////////////////////////////////////////////////////////////
-  /// @brief Holds the actual data for this AqlValue it has the following
-  /// semantics:
+  /// @brief Holds the actual data for this AqlValue
+  /// it has the following semantics:
   ///
   /// All values with a size less than 16 will be stored directly in this
   /// AqlValue using the data.internal structure.
-  /// All values of a larger size will be store in data.external.
-  /// The last bit of this union will be used to identify if we have to use
+  /// All values of a larger size will be stored in _data.external.
+  /// The last byte of this union will be used to identify if we have to use
   /// internal or external.
   /// Delete of the Buffer should free every structure that is not using the
-  /// VPack external value type.
+  /// VPack external or reference value type.
   //////////////////////////////////////////////////////////////////////////////
 
  private:
   union {
     char internal[16];
     arangodb::velocypack::Buffer<uint8_t>* external;
+    uint8_t const* reference;
   } _data;
 
  public:
+  AqlValue$();
   explicit AqlValue$(arangodb::velocypack::Builder const&);
   explicit AqlValue$(arangodb::velocypack::Builder const*);
   explicit AqlValue$(arangodb::velocypack::Slice const&);
-  
-  AqlValue$();
+  AqlValue$(arangodb::velocypack::Slice const&, AqlValueType);
+  AqlValue$(int64_t, int64_t); // range
+  explicit AqlValue$(bool); // boolean type
 
   AqlValue$(AqlValue const&, arangodb::AqlTransaction*,
             TRI_document_collection_t const*);
-
-  ~AqlValue$() {
-    if (type() && _data.external != nullptr) {
-      delete _data.external;
-    }
-  }
-
+  
+  ~AqlValue$();
+  
   ////////////////////////////////////////////////////////////////////////////////
-  /// @brief Copy Constructor
+  /// @brief copy
   ////////////////////////////////////////////////////////////////////////////////
 
   AqlValue$(AqlValue$ const& other);
+  AqlValue$& operator=(AqlValue$ const& other);
+  
+  ////////////////////////////////////////////////////////////////////////////////
+  /// @brief move
+  ////////////////////////////////////////////////////////////////////////////////
+
+  AqlValue$(AqlValue$&& other);
+  AqlValue$& operator=(AqlValue$&& other);
 
   //////////////////////////////////////////////////////////////////////////////
   /// @brief Returns the type of this value. If true it uses an external pointer
   /// if false it uses the internal data structure
   //////////////////////////////////////////////////////////////////////////////
 
-  // Read last bit of the union
-  AqlValueType type() const;
+  AqlValueType type() const {
+    return static_cast<AqlValueType>(_data.internal[15]);
+  }
 
   //////////////////////////////////////////////////////////////////////////////
-  /// @brief Returns a slice to read this Value's data
+  /// @brief returns a slice to read this Value's data
   //////////////////////////////////////////////////////////////////////////////
 
   arangodb::velocypack::Slice slice() const;
+  
+  //////////////////////////////////////////////////////////////////////////////
+  /// @brief whether or not the value is empty / none
+  //////////////////////////////////////////////////////////////////////////////
+  
+  bool isNone() const;
+  bool isEmpty() const { return isNone(); }
+  
+  //////////////////////////////////////////////////////////////////////////////
+  /// @brief whether or not the value is a number
+  //////////////////////////////////////////////////////////////////////////////
+
+  bool isNumber() const;
+  
+  //////////////////////////////////////////////////////////////////////////////
+  /// @brief whether or not the value is an object
+  //////////////////////////////////////////////////////////////////////////////
+
+  bool isObject() const;
+  
+  //////////////////////////////////////////////////////////////////////////////
+  /// @brief whether or not the value is an array (note: this treats ranges
+  /// as arrays, too!)
+  //////////////////////////////////////////////////////////////////////////////
+
+  bool isArray() const;
+  
+  //////////////////////////////////////////////////////////////////////////////
+  /// @brief get the (array) length (note: this treats ranges as arrays, too!)
+  //////////////////////////////////////////////////////////////////////////////
+
+  size_t length() const;
+  
+  //////////////////////////////////////////////////////////////////////////////
+  /// @brief get the (array) element at position 
+  //////////////////////////////////////////////////////////////////////////////
+
+  AqlValue$ at(int64_t position) const;
+  
+  //////////////////////////////////////////////////////////////////////////////
+  /// @brief get the (object) element by name(s)
+  //////////////////////////////////////////////////////////////////////////////
+  
+  AqlValue$ get(std::string const&) const;
+  
+  AqlValue$ get(std::vector<char const*> const&) const;
 
   //////////////////////////////////////////////////////////////////////////////
   /// @brief get the numeric value of an AqlValue
@@ -436,10 +492,26 @@ struct AqlValue$ {
   int64_t toInt64() const;
   
   //////////////////////////////////////////////////////////////////////////////
-  /// @brief whether or not an AqlValue evaluates to true
+  /// @brief whether or not an AqlValue evaluates to true/false
   //////////////////////////////////////////////////////////////////////////////
 
   bool isTrue() const;
+  bool isFalse() const { return !isTrue(); }
+  
+  //////////////////////////////////////////////////////////////////////////////
+  /// @brief construct a V8 value as input for the expression execution in V8
+  //////////////////////////////////////////////////////////////////////////////
+
+  v8::Handle<v8::Value> toV8(v8::Isolate* isolate, arangodb::AqlTransaction*) const;
+
+  //////////////////////////////////////////////////////////////////////////////
+  /// @brief construct a V8 value as input for the expression execution in V8
+  /// only construct those attributes that are needed in the expression
+  //////////////////////////////////////////////////////////////////////////////
+
+  v8::Handle<v8::Value> toV8Partial(v8::Isolate* isolate,
+                                    arangodb::AqlTransaction*,
+                                    std::unordered_set<std::string> const&) const;
   
   //////////////////////////////////////////////////////////////////////////////
   /// @brief compare function for two values
@@ -450,10 +522,66 @@ struct AqlValue$ {
     // TODO: implement
     return 0;
   }
+
+ private:
+  
+  //////////////////////////////////////////////////////////////////////////////
+  /// @brief sets the value type
+  //////////////////////////////////////////////////////////////////////////////
+
+   void setType(AqlValueType type);
+
+  //////////////////////////////////////////////////////////////////////////////
+  /// @brief helper function for copy construction/assignment
+  //////////////////////////////////////////////////////////////////////////////
+
+  void copy(AqlValue$ const&);
+
+  //////////////////////////////////////////////////////////////////////////////
+  /// @brief helper function for move construction/assignment
+  //////////////////////////////////////////////////////////////////////////////
+
+  void move(AqlValue$&);
+  
+  //////////////////////////////////////////////////////////////////////////////
+  /// @brief destroy the internal data structures
+  //////////////////////////////////////////////////////////////////////////////
+
+  void destroy();
+
+  //////////////////////////////////////////////////////////////////////////////
+  /// @brief invalidates/resets a value to None
+  //////////////////////////////////////////////////////////////////////////////
+
+  void invalidate(AqlValue$&);
+  
+  //////////////////////////////////////////////////////////////////////////////
+  /// @brief get pointer of the included Range object
+  //////////////////////////////////////////////////////////////////////////////
+
+  Range* range() const;
 };
 
 static_assert(sizeof(AqlValue$) == 16, "invalid AqlValue$ size");
 
+// do not add virtual methods or data members!
+struct AqlValueReference final : public AqlValue$ {
+ public:
+  explicit AqlValueReference(arangodb::velocypack::Slice const& slice)
+      : AqlValue$(slice, AqlValueType::REFERENCE) {}
+};
+
+static_assert(sizeof(AqlValueReference) == 16, "invalid AqlValueReference size");
+
+// do not add virtual methods or data members!
+struct AqlValueDocument final : public AqlValue$ {
+ public:
+  explicit AqlValueDocument(arangodb::velocypack::Slice const& slice)
+      : AqlValue$(slice, AqlValueType::REFERENCE_STICKY) {}
+};
+
+static_assert(sizeof(AqlValueDocument) == 16, "invalid AqlValueDocument size");
+
 }  // closes namespace arangodb::aql
 }  // closes namespace arangodb
 
diff --git a/arangod/Aql/AttributeAccessor.cpp b/arangod/Aql/AttributeAccessor.cpp
index a58128ed60..bcf430afe9 100644
--- a/arangod/Aql/AttributeAccessor.cpp
+++ b/arangod/Aql/AttributeAccessor.cpp
@@ -22,14 +22,11 @@
 ////////////////////////////////////////////////////////////////////////////////
 
 #include "AttributeAccessor.h"
-#include "Basics/JsonHelper.h"
 #include "Aql/AqlItemBlock.h"
 #include "Aql/Variable.h"
+#include "Basics/VelocyPackHelper.h"
 #include "Utils/AqlTransaction.h"
 
-#include <velocypack/Slice.h>
-#include <velocypack/velocypack-aliases.h>
-
 using namespace arangodb::aql;
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -44,36 +41,23 @@ AttributeAccessor::AttributeAccessor(
   TRI_ASSERT(_variable != nullptr);
 }
 
-////////////////////////////////////////////////////////////////////////////////
-/// @brief destroy the accessor
-////////////////////////////////////////////////////////////////////////////////
-
-AttributeAccessor::~AttributeAccessor() {}
-
 ////////////////////////////////////////////////////////////////////////////////
 /// @brief execute the accessor
 ////////////////////////////////////////////////////////////////////////////////
 
-AqlValue AttributeAccessor::get(arangodb::AqlTransaction* trx,
-                                AqlItemBlock const* argv, size_t startPos,
-                                std::vector<Variable const*> const& vars,
-                                std::vector<RegisterId> const& regs) {
+AqlValue$ AttributeAccessor::get(arangodb::AqlTransaction* trx,
+                                 AqlItemBlock const* argv, size_t startPos,
+                                 std::vector<Variable const*> const& vars,
+                                 std::vector<RegisterId> const& regs) {
   size_t i = 0;
   for (auto it = vars.begin(); it != vars.end(); ++it, ++i) {
     if ((*it)->id == _variable->id) {
       // get the AQL value
-      auto& result = argv->getValueReference(startPos, regs[i]);
-
-      // extract the attribute
-      VPackSlice const slice;
-#warning TODO: fill slice from AqlValue (result)
-      VPackSlice extracted = slice.get(_attributeParts);
-#warning TODO: build result from extracted
-      return AqlValue(new arangodb::basics::Json(arangodb::basics::Json::Null));
+      return AqlValue$(argv->getValueReference(startPos, regs[i]), trx, nullptr).get(_attributeParts);
     }
     // fall-through intentional
   }
 
-  return AqlValue(new arangodb::basics::Json(arangodb::basics::Json::Null));
+  return AqlValueReference(arangodb::basics::VelocyPackHelper::NullValue());
 }
 
diff --git a/arangod/Aql/AttributeAccessor.h b/arangod/Aql/AttributeAccessor.h
index d5a15cb9e4..22cac3199c 100644
--- a/arangod/Aql/AttributeAccessor.h
+++ b/arangod/Aql/AttributeAccessor.h
@@ -42,18 +42,18 @@ struct Variable;
 class AttributeAccessor {
  public:
   AttributeAccessor(std::vector<char const*> const&, Variable const*);
-
-  ~AttributeAccessor();
+  ~AttributeAccessor() = default;
 
   //////////////////////////////////////////////////////////////////////////////
   /// @brief execute the accessor
   //////////////////////////////////////////////////////////////////////////////
 
-  AqlValue get(arangodb::AqlTransaction* trx, AqlItemBlock const*, size_t,
-               std::vector<Variable const*> const&,
-               std::vector<RegisterId> const&);
+  AqlValue$ get(arangodb::AqlTransaction* trx, AqlItemBlock const*, size_t,
+                std::vector<Variable const*> const&,
+                std::vector<RegisterId> const&);
 
  private:
+
   //////////////////////////////////////////////////////////////////////////////
   /// @brief the attribute names vector (e.g. [ "a", "b", "c" ] for a.b.c)
   //////////////////////////////////////////////////////////////////////////////
diff --git a/arangod/Aql/CalculationBlock.cpp b/arangod/Aql/CalculationBlock.cpp
index 391ab13cb0..efab0a7692 100644
--- a/arangod/Aql/CalculationBlock.cpp
+++ b/arangod/Aql/CalculationBlock.cpp
@@ -134,7 +134,7 @@ void CalculationBlock::executeExpression(AqlItemBlock* result) {
     }
 
     // execute the expression
-    AqlValue a = _expression->execute(_trx, result, i, _inVars, _inRegs);
+    AqlValue a = AqlValue(_expression->execute(_trx, result, i, _inVars, _inRegs));
 
     try {
       TRI_IF_FAILURE("CalculationBlock::executeExpression") {
diff --git a/arangod/Aql/Expression.cpp b/arangod/Aql/Expression.cpp
index 50d4d06b44..bc8409addc 100644
--- a/arangod/Aql/Expression.cpp
+++ b/arangod/Aql/Expression.cpp
@@ -138,10 +138,10 @@ void Expression::variables(std::unordered_set<Variable const*>& result) const {
 /// @brief execute the expression
 ////////////////////////////////////////////////////////////////////////////////
 
-AqlValue Expression::execute(arangodb::AqlTransaction* trx,
-                             AqlItemBlock const* argv, size_t startPos,
-                             std::vector<Variable const*> const& vars,
-                             std::vector<RegisterId> const& regs) {
+AqlValue$ Expression::execute(arangodb::AqlTransaction* trx,
+                              AqlItemBlock const* argv, size_t startPos,
+                              std::vector<Variable const*> const& vars,
+                              std::vector<RegisterId> const& regs) {
   if (!_built) {
     buildExpression();
   }
@@ -152,13 +152,16 @@ AqlValue Expression::execute(arangodb::AqlTransaction* trx,
   // and execute
   switch (_type) {
     case JSON: {
+      // TODO
       TRI_ASSERT(_data != nullptr);
-      return AqlValue(new Json(TRI_UNKNOWN_MEM_ZONE, _data, Json::NOFREE));
+      VPackBuilder builder;
+      JsonHelper::toVelocyPack(_data, builder);
+      return AqlValue$(builder);
     }
 
     case SIMPLE: {
-      return AqlValue(executeSimpleExpression(_node, trx, argv, startPos,
-                                     vars, regs, true));
+      return executeSimpleExpression(_node, trx, argv, startPos,
+                                     vars, regs, true);
     }
 
     case ATTRIBUTE: {
@@ -268,9 +271,9 @@ void Expression::invalidate() {
 bool Expression::findInArray(AqlValue$ const& left, AqlValue$ const& right,
                              arangodb::AqlTransaction* trx,
                              AstNode const* node) const {
-  TRI_ASSERT(right.slice().isArray());
+  TRI_ASSERT(right.isArray());
 
-  size_t const n = right.slice().length();
+  size_t const n = right.length();
 
   if (n > 3 && 
       (node->getMember(1)->isSorted() ||
@@ -283,10 +286,8 @@ bool Expression::findInArray(AqlValue$ const& left, AqlValue$ const& right,
     while (true) {
       // determine midpoint
       size_t m = l + ((r - l) / 2);
-      VPackSlice arrayItem = right.slice().at(m);
-      AqlValue$ arrayItemValue(arrayItem);
 
-      int compareResult = AqlValue$::Compare(trx, left, arrayItemValue, true);
+      int compareResult = AqlValue$::Compare(trx, left, AqlValue$(right.at(m).slice()), true);
 
       if (compareResult == 0) {
         // item found in the list
@@ -306,20 +307,19 @@ bool Expression::findInArray(AqlValue$ const& left, AqlValue$ const& right,
         return false;
       }
     }
-  } else {
-    // use linear search
-    for (auto const& it : VPackArrayIterator(right.slice())) {
-      // do not copy the list element we're looking at
-      int compareResult = AqlValue$::Compare(trx, left, AqlValue$(it), false);
+  } 
+    
+  // use linear search
+  for (size_t i = 0; i < n; ++i) {
+    int compareResult = AqlValue$::Compare(trx, left, AqlValue$(right.at(i).slice()), false);
 
-      if (compareResult == 0) {
-        // item found in the list
-        return true;
-      }
+    if (compareResult == 0) {
+      // item found in the list
+      return true;
     }
-
-    return false;
   }
+
+  return false;
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -571,14 +571,7 @@ AqlValue$ Expression::executeSimpleExpressionAttributeAccess(
   AqlValue$ result = executeSimpleExpression(member, trx, argv,
                                              startPos, vars, regs, false);
 
-  VPackSlice slice = result.slice();
-  if (slice.isObject()) {
-    VPackSlice value = slice.get(name);
-    if (!value.isNone()) {
-      return AqlValue$(value);
-    }
-  }
-  return AqlValue$(VelocyPackHelper::NullValue());
+  return result.get(name);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -608,12 +601,12 @@ AqlValue$ Expression::executeSimpleExpressionIndexedAccess(
   AqlValue$ result = executeSimpleExpression(member, trx, argv,
                                              startPos, vars, regs, false);
 
-  if (result.slice().isArray()) {
+  if (result.isArray()) {
     AqlValue$ indexResult = executeSimpleExpression(
         index, trx, argv, startPos, vars, regs, false);
 
-    if (indexResult.slice().isNumber()) {
-      return AqlValue$(result.slice().at(indexResult.toInt64()));
+    if (indexResult.isNumber()) {
+      return result.at(indexResult.toInt64());
     }
      
     if (indexResult.slice().isString()) {
@@ -622,33 +615,25 @@ AqlValue$ Expression::executeSimpleExpressionIndexedAccess(
       try {
         // stoll() might throw an exception if the string is not a number
         int64_t position = static_cast<int64_t>(std::stoll(value));
-        return AqlValue$(result.slice().at(position));
+        return result.at(position);
       } catch (...) {
         // no number found.
       }
     } 
 
     // fall-through to returning null
-  } else if (result.slice().isObject()) {
+  } else if (result.isObject()) {
     AqlValue$ indexResult = executeSimpleExpression(
         index, trx, argv, startPos, vars, regs, false);
 
-    if (indexResult.slice().isNumber()) {
-      std::string const indexString = std::to_string(indexResult.slice().getNumber<int64_t>());
-      VPackSlice value = result.slice().get(indexString);
-      if (!value.isNone()) {
-        return AqlValue$(value);
-      }
-      return AqlValue$(VelocyPackHelper::NullValue());
+    if (indexResult.isNumber()) {
+      std::string const indexString = std::to_string(indexResult.toInt64());
+      return result.get(indexString);
     }
      
     if (indexResult.slice().isString()) {
       std::string const indexString = indexResult.slice().copyString();
-      VPackSlice value = result.slice().get(indexString);
-      if (!value.isNone()) {
-        return AqlValue$(value);
-      }
-      return AqlValue$(VelocyPackHelper::NullValue());
+      return result.get(indexString);
     } 
     // fall-through to returning null
   }
@@ -800,16 +785,7 @@ AqlValue$ Expression::executeSimpleExpressionRange(
   AqlValue$ resultHigh = executeSimpleExpression(
       high, trx, argv, startPos, vars, regs, false);
  
-  // build a custom type for the range 
-  VPackBuilder builder;
-  uint8_t* p = builder.add(VPackValuePair(2 + 2 * sizeof(int64_t), VPackValueType::Custom));
-  *p++ = 0xf4; // custom type for range
-  *p++ = 2 * sizeof(int64_t);
-  memcpy(p, &low, sizeof(int64_t));
-  p += sizeof(int64_t);
-  memcpy(p, &high, sizeof(int64_t));
-  
-  return AqlValue$(builder);
+  return AqlValue$(resultLow.toInt64(), resultHigh.toInt64());
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -829,14 +805,12 @@ AqlValue$ Expression::executeSimpleExpressionFCall(
   auto member = node->getMemberUnchecked(0);
   TRI_ASSERT(member->type == NODE_TYPE_ARRAY);
 
+  VPackBuilder builder;
   size_t const n = member->numMembers();
+
   VPackFunctionParameters parameters;
   parameters.reserve(n);
-#warning Can we get access to query here?
-  // std::shared_ptr<VPackBuilder> builder = query->getSharedBuilder();
-  VPackBuilder builder;
 
-#warning Check if this is correct w.r.t. Memory Management
   for (size_t i = 0; i < n; ++i) {
     auto arg = member->getMemberUnchecked(i);
 
@@ -867,7 +841,7 @@ AqlValue$ Expression::executeSimpleExpressionNot(
       executeSimpleExpression(node->getMember(0), trx, argv,
                               startPos, vars, regs, false);
 
-  return AqlValue$(operand.isTrue() ? VelocyPackHelper::FalseValue() : VelocyPackHelper::TrueValue());
+  return AqlValue$(operand.isFalse());
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -926,10 +900,10 @@ AqlValue$ Expression::executeSimpleExpressionComparison(
   if (node->type == NODE_TYPE_OPERATOR_BINARY_IN ||
       node->type == NODE_TYPE_OPERATOR_BINARY_NIN) {
     // IN and NOT IN
-    if (!right.slice().isArray()) {
+    if (!right.isArray()) {
       // right operand must be a list, otherwise we return false
       // do not throw, but return "false" instead
-      return AqlValue$(VelocyPackHelper::FalseValue());
+      return AqlValue$(false);
     }
 
     bool result =
@@ -940,7 +914,7 @@ AqlValue$ Expression::executeSimpleExpressionComparison(
       result = !result;
     }
 
-    return AqlValue$(result ? VelocyPackHelper::TrueValue() : VelocyPackHelper::FalseValue());
+    return AqlValue$(result);
   }
 
   // all other comparison operators...
@@ -952,17 +926,17 @@ AqlValue$ Expression::executeSimpleExpressionComparison(
   int compareResult = AqlValue$::Compare(trx, left, right, compareUtf8);
   switch (node->type) {
     case NODE_TYPE_OPERATOR_BINARY_EQ:
-      return AqlValue$((compareResult == 0) ? VelocyPackHelper::TrueValue() : VelocyPackHelper::FalseValue());
+      return AqlValue$(compareResult == 0);
     case NODE_TYPE_OPERATOR_BINARY_NE:
-      return AqlValue$((compareResult != 0) ? VelocyPackHelper::TrueValue() : VelocyPackHelper::FalseValue());
+      return AqlValue$(compareResult != 0);
     case NODE_TYPE_OPERATOR_BINARY_LT:
-      return AqlValue$((compareResult < 0) ? VelocyPackHelper::TrueValue() : VelocyPackHelper::FalseValue());
+      return AqlValue$(compareResult < 0);
     case NODE_TYPE_OPERATOR_BINARY_LE:
-      return AqlValue$((compareResult <= 0) ? VelocyPackHelper::TrueValue() : VelocyPackHelper::FalseValue());
+      return AqlValue$(compareResult <= 0);
     case NODE_TYPE_OPERATOR_BINARY_GT:
-      return AqlValue$((compareResult > 0) ? VelocyPackHelper::TrueValue() : VelocyPackHelper::FalseValue());
+      return AqlValue$(compareResult > 0);
     case NODE_TYPE_OPERATOR_BINARY_GE:
-      return AqlValue$((compareResult >= 0) ? VelocyPackHelper::TrueValue() : VelocyPackHelper::FalseValue());
+      return AqlValue$(compareResult >= 0);
     default:
       std::string msg("unhandled type '");
       msg.append(node->getTypeString());
@@ -987,23 +961,23 @@ AqlValue$ Expression::executeSimpleExpressionArrayComparison(
       executeSimpleExpression(node->getMember(1), trx, argv,
                               startPos, vars, regs, false);
 
-  if (!left.slice().isArray()) {
+  if (!left.isArray()) {
     // left operand must be an array
     // do not throw, but return "false" instead
-    return AqlValue$(VelocyPackHelper::FalseValue());
+    return AqlValue$(false);
   }
   
   if (node->type == NODE_TYPE_OPERATOR_BINARY_ARRAY_IN ||
       node->type == NODE_TYPE_OPERATOR_BINARY_ARRAY_NIN) {
     // IN and NOT IN
-    if (!right.slice().isArray()) {
+    if (!right.isArray()) {
       // right operand must be a list, otherwise we return false
       // do not throw, but return "false" instead
-      return AqlValue$(VelocyPackHelper::FalseValue());
+      return AqlValue$(false);
     }
   }
 
-  size_t const n = left.slice().length();
+  size_t const n = left.length();
   std::pair<size_t, size_t> requiredMatches = Quantifier::RequiredMatches(n, node->getMember(2));
 
   TRI_ASSERT(requiredMatches.first <= requiredMatches.second);
@@ -1015,16 +989,15 @@ AqlValue$ Expression::executeSimpleExpressionArrayComparison(
   bool overallResult = true;
   size_t matches = 0;
   size_t numLeft = n;
- 
-  for (auto const& it : VPackArrayIterator(left.slice())) { 
-    AqlValue$ leftItemValue(it);
+
+  for (size_t i = 0; i < n; ++i) {
+    AqlValue$ leftItemValue(left.at(i));
     bool result;
 
     // IN and NOT IN
     if (node->type == NODE_TYPE_OPERATOR_BINARY_ARRAY_IN ||
         node->type == NODE_TYPE_OPERATOR_BINARY_ARRAY_NIN) {
-      result =
-          findInArray(leftItemValue, right, trx, node);
+      result = findInArray(leftItemValue, right, trx, node);
     
       if (node->type == NODE_TYPE_OPERATOR_BINARY_ARRAY_NIN) {
         // revert the result in case of a NOT IN
@@ -1084,7 +1057,7 @@ AqlValue$ Expression::executeSimpleExpressionArrayComparison(
     }
   }
       
-  return AqlValue$(overallResult ? VelocyPackHelper::TrueValue() : VelocyPackHelper::FalseValue());
+  return AqlValue$(overallResult);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -1100,14 +1073,17 @@ AqlValue$ Expression::executeSimpleExpressionTernary(
       executeSimpleExpression(node->getMember(0), trx, argv,
                               startPos, vars, regs, false);
 
+  size_t position;
   if (condition.isTrue()) {
     // return true part
-    return executeSimpleExpression(node->getMember(1), trx, argv,
-                                   startPos, vars, regs, true);
+    position = 1;
+  }
+  else {
+    // return false part
+    position = 2;
   }
 
-  // return false part
-  return executeSimpleExpression(node->getMember(2), trx, argv,
+  return executeSimpleExpression(node->getMember(position), trx, argv,
                                  startPos, vars, regs, true);
 }
 
@@ -1141,10 +1117,7 @@ AqlValue$ Expression::executeSimpleExpressionExpansion(
     
   if (offset < 0 || count <= 0) {
     // no items to return... can already stop here
-    VPackBuilder builder;
-    builder.openArray();
-    builder.close();
-    return AqlValue$(builder);
+    return AqlValueReference(VelocyPackHelper::ArrayValue());
   }
 
   // FILTER
@@ -1158,10 +1131,7 @@ AqlValue$ Expression::executeSimpleExpressionExpansion(
       filterNode = nullptr;
     } else {
       // filter expression is always false
-      VPackBuilder builder;
-      builder.openArray();
-      builder.close();
-      return AqlValue$(builder);
+      return AqlValueReference(VelocyPackHelper::ArrayValue());
     }
   }
 
@@ -1176,33 +1146,34 @@ AqlValue$ Expression::executeSimpleExpressionExpansion(
     value = executeSimpleExpression(node->getMember(0), trx,
                                     argv, startPos, vars, regs, false);
       
+    if (!value.isArray()) {
+      return AqlValueReference(VelocyPackHelper::ArrayValue());
+    }
+    
     VPackBuilder builder;
     builder.openArray();
-
-    if (!value.slice().isArray()) {
-      builder.close();
-      return AqlValue$(builder);
-    }
       
     // generate a new temporary for the flattened array
-    std::function<void(VPackSlice const&, int64_t)> flatten =
-        [&](VPackSlice const& json, int64_t level) {
-          if (!json.isArray()) {
+    std::function<void(AqlValue$ const&, int64_t)> flatten =
+        [&](AqlValue$ const& v, int64_t level) {
+          if (!v.isArray()) {
             return;
           }
 
-          for (auto const& it : VPackArrayIterator(json)) {
-            bool const isArray = it.isArray();
+          size_t const n = v.length();
+          for (size_t i = 0; i < n; ++i) {
+            AqlValue$ item(v.at(i));
+            bool const isArray = item.isArray();
 
             if (!isArray || level == levels) {
-              builder.add(it);
+              builder.add(item.slice());
             } else if (isArray && level < levels) {
-              flatten(it, level + 1);
+              flatten(item, level + 1);
             }
           }
         };
 
-    flatten(value.slice(), 1);
+    flatten(value, 1);
     builder.close();
 
     value = AqlValue$(builder);
@@ -1210,11 +1181,8 @@ AqlValue$ Expression::executeSimpleExpressionExpansion(
     value = executeSimpleExpression(node->getMember(0), trx,
                                     argv, startPos, vars, regs, false);
 
-    if (!value.slice().isArray()) {
-      VPackBuilder builder;
-      builder.openArray();
-      builder.close();
-      return AqlValue$(builder);
+    if (!value.isArray()) {
+      return AqlValueReference(VelocyPackHelper::ArrayValue());
     }
   }
 
@@ -1230,8 +1198,10 @@ AqlValue$ Expression::executeSimpleExpressionExpansion(
   VPackBuilder builder;
   builder.openArray();
 
-  for (auto const& it : VPackArrayIterator(value.slice())) {
-    setVariable(variable, it);
+  size_t const n = value.length();
+  for (size_t i = 0; i < n; ++i) {
+    AqlValue$ item(value.at(i));
+    setVariable(variable, item.slice());
 
     bool takeItem = true;
 
@@ -1299,19 +1269,19 @@ AqlValue$ Expression::executeSimpleExpressionArithmetic(
   AqlValue$ lhs = executeSimpleExpression(node->getMember(0),
                                           trx, argv, startPos, vars, regs, true);
 
-  if (lhs.slice().isObject()) {
-    return AqlValue$(VelocyPackHelper::NullValue());
+  if (lhs.isObject()) {
+    return AqlValue$(VelocyPackHelper::NullValue(), AqlValue$::AqlValueType::REFERENCE_STICKY);
   }
 
   AqlValue$ rhs = executeSimpleExpression(node->getMember(1),
                                           trx, argv, startPos, vars, regs, true);
 
-  if (rhs.slice().isObject()) {
-    return AqlValue$(VelocyPackHelper::NullValue());
+  if (rhs.isObject()) {
+    return AqlValue$(VelocyPackHelper::NullValue(), AqlValue$::AqlValueType::REFERENCE_STICKY);
   }
 
-  double const l = lhs.slice().getNumber<double>();
-  double const r = rhs.slice().getNumber<double>();
+  double const l = lhs.toDouble();
+  double const r = rhs.toDouble();
 
   VPackBuilder builder;
 
@@ -1328,17 +1298,17 @@ AqlValue$ Expression::executeSimpleExpressionArithmetic(
     case NODE_TYPE_OPERATOR_BINARY_DIV:
       if (r == 0.0) {
         RegisterWarning(_ast, "/", TRI_ERROR_QUERY_DIVISION_BY_ZERO);
-        return AqlValue$(VelocyPackHelper::NullValue());
+        return AqlValue$(VelocyPackHelper::NullValue(), AqlValue$::AqlValueType::REFERENCE_STICKY);
       }
       return AqlValue$(builder);
     case NODE_TYPE_OPERATOR_BINARY_MOD:
       if (r == 0.0) {
         RegisterWarning(_ast, "/", TRI_ERROR_QUERY_DIVISION_BY_ZERO);
-        return AqlValue$(VelocyPackHelper::NullValue());
+        return AqlValue$(VelocyPackHelper::NullValue(), AqlValue$::AqlValueType::REFERENCE_STICKY);
       }
       builder.add(VPackValue(fmod(l, r)));
       return AqlValue$(builder);
     default:
-      return AqlValue$(VelocyPackHelper::NullValue());
+      return AqlValue$(VelocyPackHelper::NullValue(), AqlValue$::AqlValueType::REFERENCE_STICKY);
   }
 }
diff --git a/arangod/Aql/Expression.h b/arangod/Aql/Expression.h
index 71410384a6..89bdfe4108 100644
--- a/arangod/Aql/Expression.h
+++ b/arangod/Aql/Expression.h
@@ -47,7 +47,6 @@ class StringBuffer;
 namespace aql {
 
 class AqlItemBlock;
-struct AqlValue;
 struct AqlValue$;
 class Ast;
 class AttributeAccessor;
@@ -169,9 +168,9 @@ class Expression {
   /// @brief execute the expression
   //////////////////////////////////////////////////////////////////////////////
 
-  AqlValue execute(arangodb::AqlTransaction* trx, AqlItemBlock const*, size_t,
-                   std::vector<Variable const*> const&,
-                   std::vector<RegisterId> const&);
+  AqlValue$ execute(arangodb::AqlTransaction* trx, AqlItemBlock const*, size_t,
+                    std::vector<Variable const*> const&,
+                    std::vector<RegisterId> const&);
 
   //////////////////////////////////////////////////////////////////////////////
   /// @brief check whether this is a JSON expression
diff --git a/arangod/Aql/IndexBlock.cpp b/arangod/Aql/IndexBlock.cpp
index 51819587ce..d6bcf90157 100644
--- a/arangod/Aql/IndexBlock.cpp
+++ b/arangod/Aql/IndexBlock.cpp
@@ -106,8 +106,8 @@ void IndexBlock::executeExpressions() {
     auto& toReplace = _nonConstExpressions[posInExpressions];
     auto exp = toReplace->expression;
     TRI_document_collection_t const* myCollection = nullptr;
-    AqlValue a = exp->execute(_trx, cur, _pos, _inVars[posInExpressions],
-                              _inRegs[posInExpressions]);
+    AqlValue a = AqlValue(exp->execute(_trx, cur, _pos, _inVars[posInExpressions],
+                              _inRegs[posInExpressions]));
     auto jsonified = a.toJson(_trx, myCollection, true);
     a.destroy();
     AstNode* evaluatedNode = ast->nodeFromJson(jsonified.json(), true);
diff --git a/arangod/Aql/TraversalBlock.cpp b/arangod/Aql/TraversalBlock.cpp
index 32f037d88c..e5a42ff09f 100644
--- a/arangod/Aql/TraversalBlock.cpp
+++ b/arangod/Aql/TraversalBlock.cpp
@@ -183,8 +183,8 @@ void TraversalBlock::executeExpressions() {
       if (it != nullptr && it->expression != nullptr) {
         // inVars and inRegs needs fixx
         TRI_document_collection_t const* myCollection = nullptr;
-        AqlValue a = it->expression->execute(_trx, cur, _pos, _inVars[i],
-                                             _inRegs[i]);
+        AqlValue a = AqlValue(it->expression->execute(_trx, cur, _pos, _inVars[i],
+                                             _inRegs[i]));
         it->compareTo.reset(new Json(a.toJson(_trx, myCollection, true)));
         a.destroy();
       }
diff --git a/arangod/Aql/V8Expression.cpp b/arangod/Aql/V8Expression.cpp
index 89ce0cdc81..7fb5a69968 100644
--- a/arangod/Aql/V8Expression.cpp
+++ b/arangod/Aql/V8Expression.cpp
@@ -21,7 +21,7 @@
 /// @author Jan Steemann
 ////////////////////////////////////////////////////////////////////////////////
 
-#include "Aql/V8Expression.h"
+#include "V8Expression.h"
 #include "Aql/AqlItemBlock.h"
 #include "Aql/Executor.h"
 #include "Aql/Query.h"
@@ -30,7 +30,7 @@
 #include "Basics/json-utilities.h"
 #include "V8/v8-conv.h"
 #include "V8/v8-utils.h"
-#include "V8Server/v8-shape-conv.h"
+#include "V8/v8-vpack.h"
 
 using namespace arangodb::aql;
 
@@ -62,11 +62,11 @@ V8Expression::~V8Expression() {
 /// @brief execute the expression
 ////////////////////////////////////////////////////////////////////////////////
 
-AqlValue V8Expression::execute(v8::Isolate* isolate, Query* query,
-                               arangodb::AqlTransaction* trx,
-                               AqlItemBlock const* argv, size_t startPos,
-                               std::vector<Variable const*> const& vars,
-                               std::vector<RegisterId> const& regs) {
+AqlValue$ V8Expression::execute(v8::Isolate* isolate, Query* query,
+                                arangodb::AqlTransaction* trx,
+                                AqlItemBlock const* argv, size_t startPos,
+                                std::vector<Variable const*> const& vars,
+                                std::vector<RegisterId> const& regs) {
   size_t const n = vars.size();
   TRI_ASSERT(regs.size() == n);  // assert same vector length
 
@@ -75,18 +75,17 @@ AqlValue V8Expression::execute(v8::Isolate* isolate, Query* query,
   v8::Handle<v8::Object> values = v8::Object::New(isolate);
 
   for (size_t i = 0; i < n; ++i) {
-    auto reg = regs[i];
+    RegisterId reg = regs[i];
 
-    auto const& value(argv->getValueReference(startPos, reg));
+    AqlValue$ value(argv->getValueReference(startPos, reg), trx, nullptr);
 
-    if (value.isEmpty()) {
+    if (value.isNone()) {
       continue;
     }
 
-    auto document = argv->getDocumentCollection(reg);
-    auto const& varname = vars[i]->name;
+    std::string const& varname = vars[i]->name;
 
-    if (hasRestrictions && value.isJson()) {
+    if (hasRestrictions && value.isObject()) {
       // check if we can get away with constructing a partial JSON object
       auto it = _attributeRestrictions.find(vars[i]);
 
@@ -94,7 +93,7 @@ AqlValue V8Expression::execute(v8::Isolate* isolate, Query* query,
         // build a partial object
         values->ForceSet(
             TRI_V8_STD_STRING(varname),
-            value.toV8Partial(isolate, trx, (*it).second, document));
+            value.toV8Partial(isolate, trx, (*it).second));
         continue;
       }
     }
@@ -103,7 +102,7 @@ AqlValue V8Expression::execute(v8::Isolate* isolate, Query* query,
 
     // build the regular object
     values->ForceSet(TRI_V8_STD_STRING(varname),
-                     value.toV8(isolate, trx, document));
+                     value.toV8(isolate, trx));
   }
 
   TRI_ASSERT(query != nullptr);
@@ -128,23 +127,6 @@ AqlValue V8Expression::execute(v8::Isolate* isolate, Query* query,
     // won't modify their arguments is unsafe
     auto constantValues = v8::Local<v8::Object>::New(isolate, _constantValues);
 
-#ifdef ARANGODB_ENABLE_FAILURE_TESTS
-    // a hash function for hashing V8 object contents
-    auto hasher =
-        [](v8::Isolate* isolate, v8::Handle<v8::Value> const obj) -> uint64_t {
-          std::unique_ptr<TRI_json_t> json(TRI_ObjectToJson(isolate, obj));
-
-          if (json == nullptr) {
-            return 0;
-          }
-
-          return TRI_FastHashJson(json.get());
-        };
-
-    // hash the constant values that we pass into V8
-    uint64_t const hash = hasher(isolate, constantValues);
-#endif
-
     v8::Handle<v8::Value> args[] = {
         values, constantValues,
         v8::Boolean::New(isolate, _numExecutions++ == 0)};
@@ -155,17 +137,6 @@ AqlValue V8Expression::execute(v8::Isolate* isolate, Query* query,
     auto func = v8::Local<v8::Function>::New(isolate, _func);
     result = func->Call(func, 3, args);
 
-#ifdef ARANGODB_ENABLE_FAILURE_TESTS
-    // now that the V8 function call is finished, check that our
-    // constants actually were not modified
-    uint64_t cmpHash = hasher(isolate, constantValues);
-
-    if (hash != 0 && cmpHash != 0) {
-      // only compare if both values are not 0
-      TRI_ASSERT(hasher(isolate, constantValues) == hash);
-    }
-#endif
-
     v8g->_query = old;
 
     Executor::HandleV8Error(tryCatch, result);
@@ -176,31 +147,21 @@ AqlValue V8Expression::execute(v8::Isolate* isolate, Query* query,
   }
 
   // no exception was thrown if we get here
-  std::unique_ptr<TRI_json_t> json;
+  VPackBuilder builder;
 
   if (result->IsUndefined()) {
     // expression does not have any (defined) value. replace with null
-    json.reset(TRI_CreateNullJson(TRI_UNKNOWN_MEM_ZONE));
+    builder.add(VPackValue(VPackValueType::Null));
   } else {
     // expression had a result. convert it to JSON
-    if (_isSimple) {
-      json.reset(TRI_ObjectToJsonSimple(isolate, result));
-    } else {
-      json.reset(TRI_ObjectToJson(isolate, result));
+    int res = TRI_V8ToVPack(isolate, builder, result, false);
+
+    if (res != TRI_ERROR_NO_ERROR) {
+      THROW_ARANGO_EXCEPTION(res);
     }
+    // TODO: what does _isSimple do here?
   }
 
-  if (json.get() == nullptr) {
-    THROW_ARANGO_EXCEPTION(TRI_ERROR_OUT_OF_MEMORY);
-  }
-
-  auto j = new arangodb::basics::Json(TRI_UNKNOWN_MEM_ZONE, json.get());
-  json.release();
-  return AqlValue(j);
+  return AqlValue$(builder);
 }
 
-// Local Variables:
-// mode: outline-minor
-// outline-regexp: "/// @brief\\|/// {@inheritDoc}\\|/// @page\\|//
-// --SECTION--\\|/// @\\}"
-// End
diff --git a/arangod/Aql/V8Expression.h b/arangod/Aql/V8Expression.h
index dc4e200a77..527400db7a 100644
--- a/arangod/Aql/V8Expression.h
+++ b/arangod/Aql/V8Expression.h
@@ -27,6 +27,7 @@
 #include "Basics/Common.h"
 #include "Aql/AqlValue.h"
 #include "Aql/types.h"
+
 #include <v8.h>
 
 namespace arangodb {
@@ -37,6 +38,7 @@ class Query;
 struct Variable;
 
 struct V8Expression {
+
   //////////////////////////////////////////////////////////////////////////////
   /// @brief create the v8 expression
   //////////////////////////////////////////////////////////////////////////////
@@ -68,10 +70,10 @@ struct V8Expression {
   /// @brief execute the expression
   //////////////////////////////////////////////////////////////////////////////
 
-  AqlValue execute(v8::Isolate* isolate, Query* query,
-                   arangodb::AqlTransaction*, AqlItemBlock const*, size_t,
-                   std::vector<Variable const*> const&,
-                   std::vector<RegisterId> const&);
+  AqlValue$ execute(v8::Isolate* isolate, Query* query,
+                    arangodb::AqlTransaction*, AqlItemBlock const*, size_t,
+                    std::vector<Variable const*> const&,
+                    std::vector<RegisterId> const&);
 
   //////////////////////////////////////////////////////////////////////////////
   /// @brief the isolate used when executing and destroying the expression
diff --git a/lib/Basics/VelocyPackHelper.cpp b/lib/Basics/VelocyPackHelper.cpp
index 7f0665c0a6..b09020f6f5 100644
--- a/lib/Basics/VelocyPackHelper.cpp
+++ b/lib/Basics/VelocyPackHelper.cpp
@@ -64,6 +64,13 @@ static VPackBuilder TrueBuilder;
 
 static VPackBuilder FalseBuilder;
 
+////////////////////////////////////////////////////////////////////////////////
+/// @brief "constant" global object for empty ARRAYs which can be shared by all
+/// expressions but must never be freed
+////////////////////////////////////////////////////////////////////////////////
+
+static VPackBuilder ArrayBuilder;
+
 
 // attribute exclude handler for skipping over system attributes
 struct SystemAttributeExcludeHandler : public VPackAttributeExcludeHandler {
@@ -115,9 +122,15 @@ void VelocyPackHelper::initialize() {
   // initialize exclude handler for system attributes
   ExcludeHandler.reset(new SystemAttributeExcludeHandler);
 
+  // Null value
   NullBuilder.add(VPackValue(VPackValueType::Null));
+  // True value
   TrueBuilder.add(VPackValue(true));
+  // False value
   FalseBuilder.add(VPackValue(false));
+  // Array value (empty)
+  ArrayBuilder.openArray();
+  ArrayBuilder.close();
 }
 
 arangodb::velocypack::Slice VelocyPackHelper::NullValue() {
@@ -131,6 +144,10 @@ arangodb::velocypack::Slice VelocyPackHelper::TrueValue() {
 arangodb::velocypack::Slice VelocyPackHelper::FalseValue() {
   return FalseBuilder.slice(); 
 }
+
+arangodb::velocypack::Slice VelocyPackHelper::ArrayValue() {
+  return ArrayBuilder.slice(); 
+}
   
 ////////////////////////////////////////////////////////////////////////////////
 /// @brief return the (global) attribute exclude handler instance
diff --git a/lib/Basics/VelocyPackHelper.h b/lib/Basics/VelocyPackHelper.h
index 15330908b8..2e9d0276a7 100644
--- a/lib/Basics/VelocyPackHelper.h
+++ b/lib/Basics/VelocyPackHelper.h
@@ -212,6 +212,7 @@ class VelocyPackHelper {
   static arangodb::velocypack::Slice NullValue();
   static arangodb::velocypack::Slice TrueValue();
   static arangodb::velocypack::Slice FalseValue();
+  static arangodb::velocypack::Slice ArrayValue();
 };
 }
 }