diff --git a/src/constants/symbols.ts b/src/constants/symbols.ts
new file mode 100644
index 00000000..1d314c43
--- /dev/null
+++ b/src/constants/symbols.ts
@@ -0,0 +1,2 @@
+// tslint:disable-next-line:variable-name
+export const AttributeMetadata = Symbol('AttributeMetadata');
diff --git a/src/decorators/attribute.decorator.ts b/src/decorators/attribute.decorator.ts
index 80dc51d1..31782fa2 100644
--- a/src/decorators/attribute.decorator.ts
+++ b/src/decorators/attribute.decorator.ts
@@ -1,4 +1,5 @@
 import { format, parse } from 'date-fns';
+import { AttributeMetadata } from '../constants/symbols';
 
 export function Attribute(serializedName?: string) {
   return function (target: any, propertyName: string) {
@@ -16,26 +17,43 @@ export function Attribute(serializedName?: string) {
       return value;
     };
 
-    const saveAnnotations = function (hasDirtyAttributes: boolean, oldValue: any, newValue: any, isNew: boolean) {
-      const annotations = Reflect.getMetadata('Attribute', target) || {};
-      const targetType = Reflect.getMetadata('design:type', target, propertyName);
+    const saveAnnotations = function () {
+      const metadata = Reflect.getMetadata('Attribute', target) || {};
+
+      metadata[propertyName] = {
+        marked: true
+      };
+
+      Reflect.defineMetadata('Attribute', metadata, target);
 
       const mappingMetadata = Reflect.getMetadata('AttributeMapping', target) || {};
       const serializedPropertyName = serializedName !== undefined ? serializedName : propertyName;
       mappingMetadata[serializedPropertyName] = propertyName;
       Reflect.defineMetadata('AttributeMapping', mappingMetadata, target);
+    };
+
+    const setMetadata = function (
+      hasDirtyAttributes: boolean,
+      instance: any,
+      oldValue: any,
+      newValue: any,
+      isNew: boolean
+    ) {
+      const targetType = Reflect.getMetadata('design:type', target, propertyName);
+
+      if (!instance[AttributeMetadata]) {
+        instance[AttributeMetadata] = {};
+      }
 
       const propertyHasDirtyAttributes = typeof oldValue === 'undefined' && !isNew ? false : hasDirtyAttributes;
 
-      annotations[propertyName] = {
+      instance[AttributeMetadata][propertyName] = {
         newValue,
         oldValue,
         serializedName,
         hasDirtyAttributes: propertyHasDirtyAttributes,
         serialisationValue: converter(targetType, newValue, true)
       };
-
-      Reflect.defineMetadata('Attribute', annotations, target);
     };
 
     const getter = function () {
@@ -47,13 +65,13 @@ export function Attribute(serializedName?: string) {
       const convertedValue = converter(targetType, newVal);
 
       if (convertedValue !== this['_' + propertyName]) {
-        saveAnnotations(true, this['_' + propertyName], newVal, !this.id);
+        setMetadata(true, this, this['_' + propertyName], newVal, !this.id);
         this['_' + propertyName] = convertedValue;
       }
     };
 
     if (delete target[propertyName]) {
-      saveAnnotations(false, undefined, target[propertyName], target.id);
+      saveAnnotations();
       Object.defineProperty(target, propertyName, {
         get: getter,
         set: setter,
diff --git a/src/models/json-api.model.ts b/src/models/json-api.model.ts
index 089db8f3..5721360a 100644
--- a/src/models/json-api.model.ts
+++ b/src/models/json-api.model.ts
@@ -5,6 +5,7 @@ import { Observable } from 'rxjs/Observable';
 import { JsonApiDatastore, ModelType } from '../services/json-api-datastore.service';
 import { ModelConfig } from '../interfaces/model-config.interface';
 import * as _ from 'lodash';
+import { AttributeMetadata } from '../constants/symbols';
 
 export class JsonApiModel {
   id: string;
@@ -26,12 +27,12 @@ export class JsonApiModel {
   }
 
   save(params?: any, headers?: Headers): Observable<this> {
-    const attributesMetadata: any = Reflect.getMetadata('Attribute', this);
+    const attributesMetadata: any = this[AttributeMetadata];
     return this._datastore.saveRecord(attributesMetadata, this, params, headers);
   }
 
   get hasDirtyAttributes() {
-    const attributesMetadata: any = Reflect.getMetadata('Attribute', this);
+    const attributesMetadata: any = this[AttributeMetadata];
     let hasDirtyAttributes = false;
     for (const propertyName in attributesMetadata) {
       if (attributesMetadata.hasOwnProperty(propertyName)) {
@@ -47,7 +48,7 @@ export class JsonApiModel {
   }
 
   rollbackAttributes(): void {
-    const attributesMetadata: any = Reflect.getMetadata('Attribute', this);
+    const attributesMetadata: any = this[AttributeMetadata];
     let metadata: any;
     for (const propertyName in attributesMetadata) {
       if (attributesMetadata.hasOwnProperty(propertyName)) {
@@ -62,7 +63,8 @@ export class JsonApiModel {
         }
       }
     }
-    Reflect.defineMetadata('Attribute', attributesMetadata, this);
+
+    this[AttributeMetadata] = attributesMetadata;
   }
 
   get modelConfig(): ModelConfig {
diff --git a/src/services/json-api-datastore.service.ts b/src/services/json-api-datastore.service.ts
index 28bbd15f..73731c85 100644
--- a/src/services/json-api-datastore.service.ts
+++ b/src/services/json-api-datastore.service.ts
@@ -13,6 +13,7 @@ import { JsonApiQueryData } from '../models/json-api-query-data';
 import * as qs from 'qs';
 import { DatastoreConfig } from '../interfaces/datastore-config.interface';
 import { ModelConfig } from '../interfaces/model-config.interface';
+import { AttributeMetadata } from '../constants/symbols';
 
 export type ModelType<T extends JsonApiModel> = { new(datastore: JsonApiDatastore, data: any): T; };
 
@@ -371,7 +372,7 @@ export class JsonApiDatastore {
   private resetMetadataAttributes<T extends JsonApiModel>(res: T, attributesMetadata: any, modelType: ModelType<T>) {
     // TODO check why is attributesMetadata from the arguments never used
     // tslint:disable-next-line:no-param-reassign
-    attributesMetadata = Reflect.getMetadata('Attribute', res);
+    attributesMetadata = res[AttributeMetadata];
 
     for (const propertyName in attributesMetadata) {
       if (attributesMetadata.hasOwnProperty(propertyName)) {
@@ -383,7 +384,7 @@ export class JsonApiDatastore {
       }
     }
 
-    Reflect.defineMetadata('Attribute', attributesMetadata, res);
+    res[AttributeMetadata] = attributesMetadata;
     return res;
   }