diff --git a/src/ts/@loafer/context/decorator/Configuration.ts b/src/ts/@loafer/context/decorator/Configuration.ts
index 9d64ee4..d4bc3f2 100644
--- a/src/ts/@loafer/context/decorator/Configuration.ts
+++ b/src/ts/@loafer/context/decorator/Configuration.ts
@@ -3,11 +3,12 @@ import ConfigurationDefinition from '@loafer/context/definition/ConfigurationDef
 import { getConfigurationDefinition } from '@loafer/context/util/metadata';
 
 import GetAppContext from '@loafer/context';
-import { DEFAULT_QUALIFIER, InjectableSterotype } from '@loafer/pouches/constants';
+import { InjectableSterotype } from '@loafer/pouches/constants';
 import DefaultPouchFactory from '@loafer/pouches/factory/implement/DefaultPouchFactory';
 import PouchDefinitionRegistry from '@loafer/pouches/factory/registry/PouchDefinitionRegistry';
+import { validateQualifier } from '@loafer/pouches/util/qualifier';
 
-const Configuration = (qualifier: string | symbol = DEFAULT_QUALIFIER ) => createDecorator('Configuration', {
+const Configuration = (qualifier?: string | symbol ) => createDecorator('Configuration', {
   classDecorator: <TFunction extends Function>(target: TFunction): TFunction | void => {
     let configurationDefinition: ConfigurationDefinition = getConfigurationDefinition(target.prototype, false);
     if (undefined !== configurationDefinition) {
@@ -16,7 +17,7 @@ const Configuration = (qualifier: string | symbol = DEFAULT_QUALIFIER ) => creat
 
     configurationDefinition = getConfigurationDefinition(target, true);
     configurationDefinition.Stereotype = InjectableSterotype.CONFIGURATION;
-    configurationDefinition.Qualifier = qualifier;
+    configurationDefinition.Qualifier = validateQualifier(target.prototype, qualifier);
 
     let pouchFactory: DefaultPouchFactory = GetAppContext().getPouchFactory();
     let pouchDefinitionRegistry = <PouchDefinitionRegistry>pouchFactory;
diff --git a/src/ts/@loafer/context/decorator/Injectable.ts b/src/ts/@loafer/context/decorator/Injectable.ts
index 8e9dd8b..df8b8f5 100644
--- a/src/ts/@loafer/context/decorator/Injectable.ts
+++ b/src/ts/@loafer/context/decorator/Injectable.ts
@@ -3,19 +3,19 @@ import InjectableDefinition from '@loafer/context/definition/InjectableDefinitio
 import { getInjectableDefinition } from '@loafer/context/util/metadata';
 
 import GetAppContext from '@loafer/context';
-import { DEFAULT_QUALIFIER } from '@loafer/pouches/constants';
+import { validateQualifier } from '@loafer/pouches/util/qualifier';
 import DefaultPouchFactory from '@loafer/pouches/factory/implement/DefaultPouchFactory';
 import PouchDefinitionRegistry from '@loafer/pouches/factory/registry/PouchDefinitionRegistry';
 
-const Injectable = (qualifier: string | symbol = DEFAULT_QUALIFIER ) => createDecorator('Injectable', {
+const Injectable = (qualifier?: string | symbol ) => createDecorator('Injectable', {
   classDecorator: <TFunction extends Function>(target: TFunction): TFunction | void => {
     let injectableDefinition: InjectableDefinition = getInjectableDefinition(target.prototype, false);
     if (undefined !== injectableDefinition) {
       throw new Error('Cannot apply @Injectable decorator multiple times.');
     }
 
-    injectableDefinition = getInjectableDefinition(target, true);
-    injectableDefinition.Qualifier = qualifier;
+    injectableDefinition = getInjectableDefinition(target.prototype, true);
+    injectableDefinition.Qualifier = validateQualifier(target.prototype, qualifier);
 
     let pouchFactory: DefaultPouchFactory = GetAppContext().getPouchFactory();
     let pouchDefinitionRegistry = <PouchDefinitionRegistry>pouchFactory;
diff --git a/src/ts/@loafer/context/decorator/Service.ts b/src/ts/@loafer/context/decorator/Service.ts
index 182c5c8..216f151 100644
--- a/src/ts/@loafer/context/decorator/Service.ts
+++ b/src/ts/@loafer/context/decorator/Service.ts
@@ -3,11 +3,12 @@ import InjectableDefinition from '@loafer/context/definition/InjectableDefinitio
 import { getInjectableDefinition } from '@loafer/context/util/metadata';
 
 import GetAppContext from '@loafer/context';
-import { DEFAULT_QUALIFIER, InjectableSterotype } from '@loafer/pouches/constants';
+import { InjectableSterotype } from '@loafer/pouches/constants';
+import { validateQualifier } from '@loafer/pouches/util/qualifier';
 import DefaultPouchFactory from '@loafer/pouches/factory/implement/DefaultPouchFactory';
 import PouchDefinitionRegistry from '@loafer/pouches/factory/registry/PouchDefinitionRegistry';
 
-const Service = (qualifier: string | symbol = DEFAULT_QUALIFIER ) => createDecorator('Service', {
+const Service = (qualifier?: string | symbol ) => createDecorator('Service', {
   classDecorator: <TFunction extends Function>(target: TFunction): TFunction | void => {
     let injectableDefinition: InjectableDefinition = getInjectableDefinition(target.prototype, false);
     if (undefined !== injectableDefinition) {
@@ -16,7 +17,7 @@ const Service = (qualifier: string | symbol = DEFAULT_QUALIFIER ) => createDecor
 
     injectableDefinition = getInjectableDefinition(target, true);
     injectableDefinition.Stereotype = InjectableSterotype.SERVICE;
-    injectableDefinition.Qualifier = qualifier;
+    injectableDefinition.Qualifier = validateQualifier(target.prototype, qualifier);
 
     let pouchFactory: DefaultPouchFactory = GetAppContext().getPouchFactory();
     let pouchDefinitionRegistry = <PouchDefinitionRegistry>pouchFactory;
diff --git a/src/ts/@loafer/pouches/constants/index.ts b/src/ts/@loafer/pouches/constants/index.ts
index c4e0621..966e41b 100644
--- a/src/ts/@loafer/pouches/constants/index.ts
+++ b/src/ts/@loafer/pouches/constants/index.ts
@@ -1,5 +1,3 @@
 export * from './reflect';
 export * from './stereotype';
 export * from './types';
-
-export const DEFAULT_QUALIFIER = Symbol('__DEFAULT_QUALIFIER__');
diff --git a/src/ts/@loafer/pouches/definition/InjectDefinition.ts b/src/ts/@loafer/pouches/definition/InjectDefinition.ts
index 3fef19c..f6caf12 100644
--- a/src/ts/@loafer/pouches/definition/InjectDefinition.ts
+++ b/src/ts/@loafer/pouches/definition/InjectDefinition.ts
@@ -1,5 +1,5 @@
-import * as METADATA from '@loafer/pouches/constants';
-import { DEFAULT_QUALIFIER, InjectSterotype } from '@loafer/pouches/constants';
+import { InjectSterotype } from '@loafer/pouches/constants';
+import { validateQualifier } from '@loafer/pouches/util/qualifier';
 import InjectConfig from '@loafer/pouches/decorator/InjectConfig';
 import * as CoreConstants from '@loafer/core/constants';
 
@@ -27,9 +27,7 @@ class InjectDefinition {
    * addInject
    */
   public addInject(injectConfig: InjectConfig, propertyKey: string | symbol, parameterIndex?: number): void {
-    if (undefined === injectConfig.qualifier) {
-      injectConfig.qualifier = DEFAULT_QUALIFIER;
-    }
+    injectConfig.qualifier = validateQualifier(this.target, injectConfig.qualifier);
     if (undefined === injectConfig.required) {
       injectConfig.required = false;
     }
diff --git a/src/ts/@loafer/pouches/factory/implement/AbstractPouchFactory.ts b/src/ts/@loafer/pouches/factory/implement/AbstractPouchFactory.ts
index 136bd1d..56920cc 100644
--- a/src/ts/@loafer/pouches/factory/implement/AbstractPouchFactory.ts
+++ b/src/ts/@loafer/pouches/factory/implement/AbstractPouchFactory.ts
@@ -9,7 +9,7 @@ import DefaultSingletonPouchRegistry from '@loafer/pouches/factory/implement/Def
 
 
 abstract class AbstractPouchFactory extends DefaultSingletonPouchRegistry implements PouchDefinitionRegistry {
-  protected pouchDefinitionMap: Map<Object, Map<string | symbol, PouchDefinition>>;
+  protected pouchDefinitionMap: Map<string | symbol, Map<Object, PouchDefinition>>;
   public constructor() {
     super();
     this.pouchDefinitionMap = new Map();
@@ -17,33 +17,35 @@ abstract class AbstractPouchFactory extends DefaultSingletonPouchRegistry implem
 
   public registerPouchDefinition(pouchDefinition: PouchDefinition): void {
     let type = pouchDefinition.Type;
-    let qualifier = pouchDefinition.Qualifier;
+    let qualifier = validateQualifier(type, pouchDefinition.Qualifier);
 
     if (this.hasPouchDefinition(type, qualifier)) {
       throw new Error(`Pouch Definition[${type.constructor.name}:${qualifier}] is exist already`);
     }
-    let map = this.pouchDefinitionMap.get(type);
+    let map = this.pouchDefinitionMap.get(qualifier);
     if (undefined === map) {
       map = new Map();
+      this.pouchDefinitionMap.set(qualifier, map);
     }
-    map.set(qualifier, pouchDefinition);
+    map.set(type, pouchDefinition);
   }
   public removePouchDefinition(type: Object, qualifier?: string | symbol): void {
-    if (!this.hasPouchDefinition(type, qualifier)) {
+    const _qualifier = validateQualifier(type, qualifier);
+    if (!this.hasPouchDefinition(type, _qualifier)) {
       throw new Error(`Pouch Definition[${type.constructor.name}:${qualifier}] is not exist`);
     }
-    const _qualifier = validateQualifier(qualifier);
-    this.pouchDefinitionMap.get(type).delete(_qualifier);
-    if (0 === this.pouchDefinitionMap.get(type).size) {
-      this.pouchDefinitionMap.delete(type);
+    this.pouchDefinitionMap.get(_qualifier).delete(type);
+    if (0 === this.pouchDefinitionMap.get(_qualifier).size) {
+      this.pouchDefinitionMap.delete(_qualifier);
     }
   }
   public getPouchDefinition(type: Object, qualifier?: string | symbol): PouchDefinition {
-    if (!this.pouchDefinitionMap.has(type)) {
+    const _qualifier = validateQualifier(type, qualifier);
+
+    if (!this.pouchDefinitionMap.has(_qualifier)) {
       return undefined;
     }
-    const _qualifier = validateQualifier(qualifier);
-    return this.pouchDefinitionMap.get(type).get(qualifier);
+    return this.pouchDefinitionMap.get(_qualifier).get(type);
   }
   public hasPouchDefinition(type: Object, qualifier?: string | symbol): boolean {
     return undefined === this.getPouchDefinition(type, qualifier) ? false : true;
diff --git a/src/ts/@loafer/pouches/factory/implement/DefaultPouchFactory.ts b/src/ts/@loafer/pouches/factory/implement/DefaultPouchFactory.ts
index fc33ef6..ce8cc5c 100644
--- a/src/ts/@loafer/pouches/factory/implement/DefaultPouchFactory.ts
+++ b/src/ts/@loafer/pouches/factory/implement/DefaultPouchFactory.ts
@@ -5,8 +5,10 @@ import {
 
 import {
   PouchScope,
-  DEFAULT_QUALIFIER,
 } from '@loafer/pouches/constants';
+import {
+  validateQualifier,
+} from '@loafer/pouches/util/qualifier';
 
 import PouchFactory from '@loafer/pouches/factory/PouchFactory';
 import AbstractPouchFactory from '@loafer/pouches/factory/implement/AbstractPouchFactory';
@@ -19,7 +21,7 @@ class DefaultPouchFactory extends AbstractPouchFactory implements PouchFactory,
   }
 
   public getPouch<T>(type: Construtorable<T>, ...args: any[]): T {
-    let qualifier = DEFAULT_QUALIFIER;
+    let qualifier = validateQualifier(type.prototype, undefined);
     return this.getPouchByQualifier(type, qualifier, args);
   }
 
diff --git a/src/ts/@loafer/pouches/factory/implement/DefaultSingletonPouchRegistry.ts b/src/ts/@loafer/pouches/factory/implement/DefaultSingletonPouchRegistry.ts
index 1c48204..4fe399f 100644
--- a/src/ts/@loafer/pouches/factory/implement/DefaultSingletonPouchRegistry.ts
+++ b/src/ts/@loafer/pouches/factory/implement/DefaultSingletonPouchRegistry.ts
@@ -9,33 +9,44 @@ import {
 } from '@loafer/pouches/util/qualifier';
 
 class DefaultSingletonPouchRegistry implements SingletonPouchRegistry {
-  protected singletonInstanceMap: Map<Object, Map<string | symbol, any>>;
+  protected singletonInstanceMap: Map<string | symbol, Map<Object, any>>;
 
   protected constructor() {
   }
 
   public registerSingleton(pouch: any, qualifier?: string | symbol): void {
-    let type = Object.getPrototypeOf(pouch);
-    const _qualifier = validateQualifier(qualifier);
+    let type: Object = Object.getPrototypeOf(pouch);
+    const _qualifier = validateQualifier(type, qualifier);
 
-    if (this.hasSingleton(type, qualifier)) {
+    if (this._hasSingleton(type, _qualifier)) {
       throw new Error(`Pouch Definition[${type.constructor.name}:${qualifier}] is exist already`);
     }
-    let map = this.singletonInstanceMap.get(type);
+    let map = this.singletonInstanceMap.get(_qualifier);
     if (undefined === map) {
       map = new Map();
+      this.singletonInstanceMap.set(_qualifier, map);
     }
-    map.set(qualifier, pouch);
+    map.set(type, pouch);
   }
-  public getSingleton<T>(type: Construtorable<T>, qualifier?: string | symbol): T {
-    if (!this.singletonInstanceMap.has(type)) {
+  public getSingleton<T>(target: Construtorable<T>, qualifier?: string | symbol): T {
+    let type = target.prototype;
+    return this._getSingleton(type, qualifier);
+  }
+  public hasSingleton<T>(target: Construtorable<T>, qualifier?: string | symbol): boolean {
+    return this._hasSingleton(target.prototype, qualifier);
+  }
+
+  private _getSingleton<T>(type: Object, qualifier?: string | symbol): T {
+    const _qualifier = validateQualifier(type, qualifier);
+
+    if (!this.singletonInstanceMap.has(_qualifier)) {
       return undefined;
     }
-    const _qualifier = validateQualifier(qualifier);
-    return this.singletonInstanceMap.get(type).get(qualifier);
+    return this.singletonInstanceMap.get(_qualifier).get(type);
   }
-  public hasSingleton<T>(type: Construtorable<T>, qualifier?: string | symbol): boolean {
-    return undefined === this.getSingleton(type, qualifier) ? false : true;
+
+  private _hasSingleton(type: Object, qualifier?: string | symbol): boolean {
+    return undefined === this._getSingleton(type, qualifier) ? false : true;
   }
 }
 
diff --git a/src/ts/@loafer/pouches/util/qualifier.ts b/src/ts/@loafer/pouches/util/qualifier.ts
index be54a85..98a4beb 100644
--- a/src/ts/@loafer/pouches/util/qualifier.ts
+++ b/src/ts/@loafer/pouches/util/qualifier.ts
@@ -1,7 +1,3 @@
-import {
-  DEFAULT_QUALIFIER,
-} from '@loafer/pouches/constants';
-
-export const validateQualifier = (qualifier: string | symbol) => {
-  return undefined === qualifier ? DEFAULT_QUALIFIER : qualifier;
+export const validateQualifier = (type: Object, qualifier: string | symbol) => {
+  return undefined === qualifier ? type.constructor.name : qualifier;
 };
diff --git a/src/ts/@overflow/commons/api/Service.ts b/src/ts/@overflow/commons/api/Service.ts
index a276bed..f85872a 100644
--- a/src/ts/@overflow/commons/api/Service.ts
+++ b/src/ts/@overflow/commons/api/Service.ts
@@ -2,7 +2,7 @@ import Inject from '@loafer/pouches/decorator/Inject';
 import WebSocketRPC from '../websocket/WebSocketRPC';
 
 abstract class Service {
-  @Inject({required: false})
+  @Inject({required: true})
   private webSocketRPC: WebSocketRPC;
   private name: string;
   protected constructor(name: string) {