diff --git a/package.json b/package.json
index 4039f2a..9c2b9c3 100644
--- a/package.json
+++ b/package.json
@@ -31,7 +31,7 @@
     "document": "typedoc --out docs --excludeNotExported --excludePrivate --disableOutputCheck --gitRevision master --exclude \"**/+(as-proto|as-static)/**/*ts\"",
     "prepare-github-pages": "npm run document && echo \"\" > ./docs/.nojekyll",
     "test": "nyc mocha --recursive --compilers ts:ts-node/register src/*.spec.ts src/**/*.spec.ts",
-    "cover": "nyc report --reporter=text-lcov | coveralls"
+    "cover": "nyc report --reporter=text-lcov | codecov"
   },
   "author": "alisahinozcelik@gmail.com",
   "license": "MIT",
@@ -43,7 +43,7 @@
     "@types/chai": "^4.1.6",
     "@types/mocha": "^5.2.5",
     "chai": "^4.2.0",
-    "coveralls": "^3.0.2",
+    "codecov.io": "^0.1.6",
     "mocha": "^5.2.0",
     "nyc": "^13.1.0",
     "ts-node": "^7.0.1",
diff --git a/src/smart-map.spec.ts b/src/smart-map.spec.ts
new file mode 100644
index 0000000..01ca950
--- /dev/null
+++ b/src/smart-map.spec.ts
@@ -0,0 +1,82 @@
+import { expect, assert } from 'chai';
+import 'mocha';
+
+import { SmartMap } from "./smart-map";
+
+describe('SmartMap Class', () => {
+  let map: SmartMap;
+
+  beforeEach(() => {
+    map = new SmartMap();
+  });
+
+  it('should construct properly', () => {
+    const mapWithValues = new SmartMap([['key', 'value'], ['key2', 'value2']]);
+
+    assert.isDefined(map);
+    assert.isDefined(mapWithValues);
+    expect([...mapWithValues.entries()]).to.be.eql([...new Map([['key', 'value'], ['key2', 'value2']]).entries()]);
+  });
+
+  it('should set a value by primitive type keys', () => {
+    map.set(1, "number");
+    map.set("string", "string");
+    map.set(true, "boolean");
+    map.set(Symbol(), "symbol");
+    map.set(undefined, "undefined");
+
+    expect(map.size).to.eq(5);
+  });
+
+  it('should set a value by object type keys', () => {
+    const anObj = {};
+
+    map.set(anObj, "foo");
+    expect(map.has(anObj)).to.be.true;
+  });
+
+  it('should store object keys in weakmap storage', () => {
+    const anObj = {};
+
+    map.set(anObj, "foo");
+
+    expect(map.size).to.eq(0);
+    expect(map.has(anObj)).to.be.true;
+  });
+
+  it('should check correctly when has method called via both primitive and object keys', () => {
+    const anObj = {};
+
+    map.set(1, "1");
+    map.set(anObj, "an object");
+
+    expect(map.has(1)).to.be.true;
+    expect(map.has(anObj)).to.be.true;
+  });
+
+  it('should get value when get method called via both primitive and object keys', () => {
+    const anObj = {};
+
+    map.set(1, "1");
+    map.set(anObj, "an object");
+
+    expect(map.get(1)).to.eq("1");
+    expect(map.get(anObj)).to.eq("an object");
+  });
+
+  it('should delete value when delete method called via both primitive and object key', () => {
+    const anObj = {};
+
+    map.set(1, "1");
+    map.set(anObj, "an object");
+
+    const primitiveResult = map.delete(1);
+    const objectResult = map.delete(anObj);
+
+    expect(primitiveResult).to.be.true;
+    expect(objectResult).to.be.true;
+
+    expect(map.size).to.eq(0);
+    expect(map.has(anObj)).to.be.false;
+  })
+});
diff --git a/src/smart-map.ts b/src/smart-map.ts
new file mode 100644
index 0000000..62d5281
--- /dev/null
+++ b/src/smart-map.ts
@@ -0,0 +1,113 @@
+// Symbols to protect overriding private methods & properties of SmartMap Class
+const KEY__WEAKMAP: unique symbol = Symbol('SmartMap.weakMap');
+
+/**
+ * ### SmartMap
+ *
+ * Like WeakMap but can also store values using primitive keys
+ *
+ * * * *
+ * Example usage:
+ * ```typescript
+ * import { SmartMap } from "@thalesrc/js-utils";
+ *
+ * const aMap = new SmartMap();
+ *
+ * aMap.set("foo", "foo");
+ * aMap.set(1, "thales rocks");
+ *
+ * console.log(aMap.size) // 2
+ *
+ * aMap.set({}, "thales rocks again");
+ * console.log(aMap.size) // 2
+ *
+ * const anObject = {};
+ * aMap.set(anObject, "thales rocks again and again");
+ * console.log(aMap.size) // 3
+ * console.log(aMap.get(anObject)) // "thales rocks again and again"
+ * ```
+ * * * *
+ * @template K Typeof Key
+ * @template V Typeof Value
+ */
+export class SmartMap<K = any, V = any> extends Map<K, V> {
+  /**
+   * Symbol refference of weakmap property
+   */
+  protected static readonly KEY__WEAKMAP = KEY__WEAKMAP;
+
+  /**
+   * Allowed key types to store them in a weakmap instance
+   */
+  public static readonly TYPES_TO_STORE_IN_WEAKMAP = Object.freeze(['object', 'function']);
+
+  /**
+   * The WeakMap object to store values with associated non-primitive (object) keys
+   */
+  protected [KEY__WEAKMAP] = new WeakMap<Object, V>();
+
+  /**
+   * Returns a boolean asserting whether a value has been associated to the key in the SmartMap object or not.
+   *
+   * @param key The key of the element to test for presence in the SmartMap object.
+   * @returns A boolean asserting whether a value has been associated to the key in the SmartMap object or not.
+   */
+  public has(key: K): boolean {
+    if (this.isStorableInWeakMap(key)) {
+      return this[KEY__WEAKMAP].has(key);
+    }
+
+    return super.has(key);
+  }
+
+  /**
+   * Returns the value associated to the key, or undefined if there is none.
+   *
+   * @param key The key of the element to return from the SmartMap object.
+   * @returns The value associated to the key
+   */
+  public get(key: K): V {
+    if (this.isStorableInWeakMap(key)) {
+      return this[KEY__WEAKMAP].get(key);
+    }
+
+    return super.get(key);
+  }
+
+  /**
+   * Sets the value for the key in the SmartMap object.
+   *
+   * @param key The key of the element to add to the SmartMap object.
+   * @param value The value of the element to add to the SmartMap object.
+   * @returns Returns the SmartMap object.
+   */
+  public set(key: K, value: V): this {
+    if (this.isStorableInWeakMap(key)) {
+      this[KEY__WEAKMAP].set(key, value);
+    } else {
+      super.set(key, value);
+    }
+
+    return this;
+  }
+
+  /**
+   * Removes the associated value from the SmartMap object,
+   *
+   * @param key The key of the element to remove from the SmartMap object.
+   * @returns `true` if an element in the SmartMap object existed and has been removed, or `false` if the element does not exist. `SmartMap.prototype.has(key)` will return false afterwards.
+   */
+  public delete(key: K): boolean {
+    return this[KEY__WEAKMAP].delete(key) || super.delete(key);
+  }
+
+  /**
+   * Returns a boolean whether if the key is storable in weakmap or not
+   *
+   * @param key Key to check if it can be stored in weakmap
+   * @returns A boolean whether if the key is storable in weakmap or not
+   */
+  protected isStorableInWeakMap(key: K): boolean {
+    return SmartMap.TYPES_TO_STORE_IN_WEAKMAP.some(_key => typeof key === _key);
+  }
+}
diff --git a/tsconfig.json b/tsconfig.json
index bd826f7..ed59b1a 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -8,7 +8,7 @@
     "experimentalDecorators": true,
     "emitDecoratorMetadata": true,
     "sourceMap": true,
-    "target": "es5",
+    "target": "es6",
     "allowSyntheticDefaultImports": true,
     "declaration": true,
     "noResolve": false,