diff --git a/src/container-instance.class.ts b/src/container-instance.class.ts
index d5c91237..b0005f25 100644
--- a/src/container-instance.class.ts
+++ b/src/container-instance.class.ts
@@ -8,7 +8,6 @@ import { ServiceMetadata } from './interfaces/service-metadata.interface.';
 import { AsyncInitializedService } from './types/AsyncInitializedService';
 import { MissingInitializedPromiseError } from './error/MissingInitializedPromiseError';
 
-
 /**
  * TypeDI can have multiple containers.
  * One container is ContainerInstance.
@@ -122,7 +121,7 @@ export class ContainerInstance {
    * Like get, but returns a promise of a service that recursively resolves async properties.
    * Used when service defined with asyncInitialization: true flag.
    */
-  getAsync<T>(type: ObjectType<T>): Promise<T>;
+  getAsync<T>(type: Constructable<T>): Promise<T>;
 
   /**
    * Like get, but returns a promise of a service that recursively resolves async properties.
@@ -498,9 +497,9 @@ export class ContainerInstance {
     if (type) this.applyPropertyHandlers(type, value);
 
     if (value instanceof AsyncInitializedService || service.asyncInitialization) {
-      return new Promise((resolve) => {
+      return new Promise(resolve => {
         if (!(value.initialized instanceof Promise) && service.asyncInitialization) {
-            throw new MissingInitializedPromiseError(service.value);
+          throw new MissingInitializedPromiseError(service.value);
         }
 
         value.initialized.then(() => resolve(value));
diff --git a/src/container.class.ts b/src/container.class.ts
index 1faf2865..3bbe4ce5 100644
--- a/src/container.class.ts
+++ b/src/container.class.ts
@@ -5,7 +5,6 @@ import { Constructable } from './types/constructable.type';
 import { ServiceIdentifier } from './types/service-identifier.type';
 import { ServiceMetadata } from './interfaces/service-metadata.interface.';
 
-
 /**
  * Service container.
  */
@@ -110,7 +109,7 @@ export class Container {
    * Like get, but returns a promise of a service that recursively resolves async properties.
    * Used when service defined with asyncInitialization: true flag.
    */
-  static getAsync<T>(type: ObjectType<T>): Promise<T>;
+  static getAsync<T>(type: Constructable<T>): Promise<T>;
 
   /**
    * Like get, but returns a promise of a service that recursively resolves async properties.
diff --git a/test/decorators/Service.spec.ts b/test/decorators/Service.spec.ts
index ba5c601a..e09a6568 100644
--- a/test/decorators/Service.spec.ts
+++ b/test/decorators/Service.spec.ts
@@ -172,35 +172,35 @@ describe('Service Decorator', function () {
     });
 
     expect(Container.get(TestService)).toBe('TEST_STRING');
+  });
+
+  it('should support services with asynchronous initialization', async function () {
+    @Service({ asyncInitialization: true })
+    class Engine {
+      ignition: string = 'off';
+      initialized: Promise<any>;
 
-    it('should support services with asynchronous initialization', async function () {
-      @Service({ asyncInitialization: true })
-      class Engine {
-        ignition: string = 'off';
-        initialized: Promise<any>;
-
-        constructor() {
-          this.initialized = this.initialize();
-        }
-
-        protected initialize() {
-          return new Promise(resolve => {
-            setTimeout(() => {
-              this.ignition = 'running';
-              resolve();
-            }, 300);
-          });
-        }
+      constructor() {
+        this.initialized = this.initialize();
       }
 
-      @Service()
-      class Car {
-        constructor(public engine: Engine) {}
+      protected initialize() {
+        return new Promise(resolve => {
+          setTimeout(() => {
+            this.ignition = 'running';
+            resolve();
+          }, 300);
+        });
       }
+    }
+
+    @Service()
+    class Car {
+      constructor(public engine: Engine) {}
+    }
 
-      const car = await Container.getAsync<Car>(Car);
+    const car = await Container.getAsync<Car>(Car);
 
-      expect(car.engine.ignition).toEqual('running');
-    });
+    expect(car.engine.ignition).toEqual('running');
   });
 });