diff --git a/README.md b/README.md
index 93dab9b..df450c2 100644
--- a/README.md
+++ b/README.md
@@ -25,9 +25,9 @@ Purchase example
 ### Node.js
 
 ```js
-const GMOPG = require('gmopg').GMOPG;
+const {default: GMOPG, ENUMS} = require('gmopg');
 
-const gmopg = GMOPG.CREATE({
+const gmopg = new GMOPG({
   axios: { baseURL: 'https://p01.mul-pay.jp' },
   SiteID: 'Your SiteID',
   SitePass: 'Your SitePass',
@@ -40,14 +40,14 @@ const amount  = 1234
 
 gmopg.entryTran({
   OrderID: orderID,
-  JobCd: GMOPG.ENUMS.JobCd.Auth,
+  JobCd: ENUMS.JobCd.Auth,
   Amount: amount
 }).then((entryRes) => {
   gmopg.execTran({
     AccessID: entryRes.AccessID,
     AccessPass: entryRes.AccessPass,
     OrderID: orderID,
-    Method: GMOPG.ENUMS.Method.Lump,
+    Method: ENUMS.Method.Lump,
     CardNo: '1234123412341234',
     Expire: '2024',
     SecurityCode: '123'
@@ -55,7 +55,7 @@ gmopg.entryTran({
     gmopg.alterTran({
       AccessID: entryRes.AccessID,
       AccessPass: entryRes.AccessPass,
-      JobCd: GMOPG.ENUMS.JobCd.Sales,
+      JobCd: ENUMS.JobCd.Sales,
       Amount: amount
     }).then((alterRes) => {
       console.log(alterRes)
@@ -67,7 +67,7 @@ gmopg.entryTran({
 ### TypeScript
 
 ```ts
-import GMOPG from 'gmopg'
+import GMOPG, {ENUMS} from 'gmopg'
 
 const gmopg = new GMOPG({
   axios: { baseURL: 'https://p01.mul-pay.jp' },
@@ -82,7 +82,7 @@ const amount = 1234
 
 const entryRes = await gmopg.entryTran({
   OrderID: orderID,
-  JobCd: GMOPG.ENUMS.JobCd.Auth,
+  JobCd: ENUMS.JobCd.Auth,
   Amount: amount
 })
 
@@ -90,7 +90,7 @@ const execRes = await gmopg.execTran({
   AccessID: entryRes.AccessID,
   AccessPass: entryRes.AccessPass,
   OrderID: orderID,
-  Method: GMOPG.ENUMS.Method.Lump,
+  Method: ENUMS.Method.Lump,
   CardNo: '1234123412341234',
   Expire: '2024',
   SecurityCode: '123'
@@ -99,7 +99,7 @@ const execRes = await gmopg.execTran({
 const alterRes = await gmopg.alterTran({
   AccessID: entryRes.AccessID,
   AccessPass: entryRes.AccessPass,
-  JobCd: GMOPG.ENUMS.JobCd.Sales,
+  JobCd: ENUMS.JobCd.Sales,
   Amount: amount
 })
 ```
diff --git a/src/client.test.ts b/src/client.test.ts
index f23750e..c7420f7 100644
--- a/src/client.test.ts
+++ b/src/client.test.ts
@@ -16,7 +16,7 @@ test.beforeEach((t) => {
 })
 
 test('.post requests body correctly', async (t) => {
-  t.context.client.options = {
+  t.context.client.config.axios = {
     adapter: async (config: AxiosRequestConfig) => {
       const response: AxiosResponse = {
         data: 'AccessID=accessid&AccessPass=accesspass',
diff --git a/src/client.ts b/src/client.ts
index 31e654d..e15d27f 100644
--- a/src/client.ts
+++ b/src/client.ts
@@ -1,13 +1,21 @@
-import {AxiosInstance, AxiosResponse} from 'axios'
+import Axios, {AxiosInstance, AxiosResponse} from 'axios'
 import {BadRequest} from './errors'
+import {IConfig} from './config.interface'
+import {buildByEnv, defaults} from './config'
 import * as qs from 'qs'
+import * as merge from 'deepmerge'
 
 export default class Client {
   public client: AxiosInstance
-  public options: object = {}
+  public config: IConfig
+
+  constructor(config: IConfig = {}) {
+    this.config = merge(merge(defaults, config), buildByEnv())
+    this.client = Axios.create(this.config.axios)
+  }
 
   public async post(endpoint: string, data: any): Promise<any> {
-    const res: AxiosResponse = await this.client.post(endpoint, qs.stringify(data, { encode: false }), this.options)
+    const res: AxiosResponse = await this.client.post(endpoint, qs.stringify(data, {encode: false}), this.config.axios)
     const parsed: any = qs.parse(res.data)
 
     if (this.isError(parsed)) {
diff --git a/src/client/cardable.test.ts b/src/client/cardable.test.ts
index 7bcc0dd..f484146 100644
--- a/src/client/cardable.test.ts
+++ b/src/client/cardable.test.ts
@@ -1,23 +1,20 @@
-import anyTest, {TestInterface} from 'ava'
+import test from 'ava'
 import Axios, {AxiosRequestConfig, AxiosResponse} from 'axios'
-import Cardable from './cardable'
+import Client from '../client'
+import WithCardable from './cardable'
 import {SeqMode} from '../client.enum'
 import {IDeleteCardResult, ISaveCardResult, ISearchCardResult} from './cardable.interface'
 
-interface Context {
-  card: Cardable
-}
+const Cardable = WithCardable(Client)
+let card: any
 
-const test = anyTest as TestInterface<Context>;
-
-test.beforeEach((t) => {
-  const card = new Cardable()
+test.beforeEach(() => {
+  card = new Cardable()
   card.client = Axios.create({})
-  t.context.card = card
 })
 
 test('.defaultCardData returns default object', async (t) => {
-  const res = await t.context.card.defaultCardData()
+  const res = await card.defaultCardData()
   const expect = {
     SiteID: undefined,
     SitePass: undefined,
@@ -27,7 +24,7 @@ test('.defaultCardData returns default object', async (t) => {
 })
 
 test('.saveCard calls API and returns response', async (t) => {
-  t.context.card.options = {
+  card.config.axios = {
     adapter: async (config: AxiosRequestConfig) => {
       const response: AxiosResponse = {
         data: 'CardSeq=cardseq&CardNo=cardno&Forward=forward&Brand=brand',
@@ -46,7 +43,7 @@ test('.saveCard calls API and returns response', async (t) => {
     SitePass: 'sitepass',
     MemberID: 'memberid'
   }
-  const res = await t.context.card.saveCard(args)
+  const res = await card.saveCard(args)
 
   const expect: ISaveCardResult = {
     CardSeq: 'cardseq',
@@ -58,7 +55,7 @@ test('.saveCard calls API and returns response', async (t) => {
 })
 
 test('.deleteCard calls API and returns response', async (t) => {
-  t.context.card.options = {
+  card.config.axios = {
     adapter: async (config: AxiosRequestConfig) => {
       const response: AxiosResponse = {
         data: 'CardSeq=cardseq',
@@ -79,7 +76,7 @@ test('.deleteCard calls API and returns response', async (t) => {
     SeqMode: SeqMode.Logic,
     CardSeq: 'cardseq'
   }
-  const res = await t.context.card.deleteCard(args)
+  const res = await card.deleteCard(args)
 
   const expect: IDeleteCardResult = {
     CardSeq: 'cardseq'
@@ -88,7 +85,7 @@ test('.deleteCard calls API and returns response', async (t) => {
 })
 
 test('.searchCard calls API and returns response', async (t) => {
-  t.context.card.options = {
+  card.config.axios = {
     adapter: async (config: AxiosRequestConfig) => {
       const response: AxiosResponse = {
         data: 'CardSeq=cardseq&DefaultFlag=1&CardName=cardname&CardNo=cardno&Expire=expire&HolderName=holdername&DeleteFlag=0',
@@ -109,7 +106,7 @@ test('.searchCard calls API and returns response', async (t) => {
     SeqMode: SeqMode.Logic,
     CardSeq: 'cardseq'
   }
-  const res = await t.context.card.searchCard(args)
+  const res = await card.searchCard(args)
 
   const result: ISearchCardResult = {
     CardSeq: 'cardseq',
diff --git a/src/client/cardable.ts b/src/client/cardable.ts
index ffc452c..3bf3aea 100644
--- a/src/client/cardable.ts
+++ b/src/client/cardable.ts
@@ -1,7 +1,6 @@
-import {AxiosInstance} from 'axios'
 import * as merge from 'deepmerge'
 import Client from '../client'
-import {IConfig} from '../config.interface'
+import {Constructor} from '../util'
 import {
   IDeleteCardArgs,
   IDeleteCardResult,
@@ -11,24 +10,13 @@ import {
   ISearchCardResult
 } from './cardable.interface'
 
-export default class Cardable extends Client {
-  public name: string = 'Cardable'
-  public config: IConfig
-  public client: AxiosInstance
-  public options: object = {}
-
+export default <T extends Constructor<Client>>(Base: T) => class Cardable extends Base {
   public defaultCardData(): any {
-    let siteID
-    let sitePass
-
-    if (this.config !== undefined) {
-      siteID = this.config.SiteID
-      sitePass = this.config.SitePass
-    }
+    const {SiteID, SitePass} = this.config
 
     return {
-      SiteID: siteID,
-      SitePass: sitePass,
+      SiteID,
+      SitePass,
       MemberID: undefined
     }
   }
@@ -37,14 +25,14 @@ export default class Cardable extends Client {
     const data: ISaveCardArgs = merge(this.defaultCardData(), args)
     const parsed: any = await this.post('/payment/SaveCard.idPass', data)
 
-    return <ISaveCardResult> parsed
+    return <ISaveCardResult>parsed
   }
 
   public async deleteCard(args: IDeleteCardArgs): Promise<IDeleteCardResult> {
     const data: IDeleteCardArgs = merge(this.defaultCardData(), args)
     const parsed: any = await this.post('/payment/DeleteCard.idPass', data)
 
-    return <IDeleteCardResult> parsed
+    return <IDeleteCardResult>parsed
   }
 
   public async searchCard(args: ISearchCardArgs): Promise<ISearchCardResult[]> {
diff --git a/src/client/cvsTranable.test.ts b/src/client/cvsTranable.test.ts
index f3bbd57..8d5f111 100644
--- a/src/client/cvsTranable.test.ts
+++ b/src/client/cvsTranable.test.ts
@@ -1,23 +1,24 @@
-import anyTest, {TestInterface} from 'ava'
+import test from 'ava'
 import Axios, {AxiosRequestConfig, AxiosResponse} from 'axios'
 import {CvsCode, Status} from '../client.enum'
-import CvsTranable from './cvsTranable'
+import Client from '../client'
+import WithCvsTranable from './cvsTranable'
 import {
   ICancelCvsResult,
   IEntryTranCvsResult,
   IExecTranCvsResult
 } from './cvsTranable.interface'
 
-const test = anyTest as TestInterface<{cvsTran: CvsTranable}>;
+const CvsTranable = WithCvsTranable(Client)
+let cvsTran: any
 
-test.beforeEach((t) => {
-  const cvsTran = new CvsTranable()
+test.beforeEach(() => {
+  cvsTran = new CvsTranable()
   cvsTran.client = Axios.create({})
-  t.context.cvsTran = cvsTran
 })
 
 test('.entryTranCvs calls API and returns response', async (t) => {
-  t.context.cvsTran.options = {
+  cvsTran.config.axios = {
     adapter: async (config: AxiosRequestConfig) => {
       const response: AxiosResponse = {
         data: 'AccessID=accessid&AccessPass=accesspass',
@@ -38,7 +39,7 @@ test('.entryTranCvs calls API and returns response', async (t) => {
     Amount: 1234,
     Tax: 123
   }
-  const res = await t.context.cvsTran.entryTranCvs(args)
+  const res = await cvsTran.entryTranCvs(args)
 
   const expect: IEntryTranCvsResult = {
     AccessID: 'accessid',
@@ -48,7 +49,7 @@ test('.entryTranCvs calls API and returns response', async (t) => {
 })
 
 test('.execTranCvs calls API and returns response', async (t) => {
-  t.context.cvsTran.options = {
+  cvsTran.config.axios = {
     adapter: async (config: AxiosRequestConfig) => {
       const text = [
         'OrderID=orderid',
@@ -86,7 +87,7 @@ test('.execTranCvs calls API and returns response', async (t) => {
     ReceiptsDisp12: '09011112222',
     ReceiptsDisp13: '10:00-19:00'
   }
-  const res = await t.context.cvsTran.execTranCvs(args)
+  const res = await cvsTran.execTranCvs(args)
 
   const expect: IExecTranCvsResult = {
     OrderID: 'orderid',
@@ -104,7 +105,7 @@ test('.execTranCvs calls API and returns response', async (t) => {
 })
 
 test('.cancelCvs calls API and returns response', async (t) => {
-  t.context.cvsTran.options = {
+  cvsTran.config.axios = {
     adapter: async (config: AxiosRequestConfig) => {
       const text = [
         'OrderID=orderid',
@@ -129,7 +130,7 @@ test('.cancelCvs calls API and returns response', async (t) => {
     AccessPass: 'accesspass',
     OrderID: 'orderid'
   }
-  const res = await t.context.cvsTran.cancelCvs(args)
+  const res = await cvsTran.cancelCvs(args)
 
   const expect: ICancelCvsResult = {
     OrderID: 'orderid',
diff --git a/src/client/cvsTranable.ts b/src/client/cvsTranable.ts
index c377b32..6068a8a 100644
--- a/src/client/cvsTranable.ts
+++ b/src/client/cvsTranable.ts
@@ -1,8 +1,7 @@
-import {AxiosInstance} from 'axios'
 import * as encoding from 'encoding-japanese'
 import * as merge from 'deepmerge'
 import Client from '../client'
-import {IConfig} from '../config.interface'
+import {Constructor} from '../util'
 import {
   ICancelCvsArgs,
   ICancelCvsResult,
@@ -12,16 +11,11 @@ import {
   IExecTranCvsResult
 } from './cvsTranable.interface'
 
-export default class CvsTranable extends Client {
-  public name: string = 'CvsTranable'
-  public config: IConfig
-  public client: AxiosInstance
-  public options: object = {}
-
+export default <T extends Constructor<Client>>(Base: T) => class extends Base {
   public async entryTranCvs(args: IEntryTranCvsArgs): Promise<IEntryTranCvsResult> {
     const defaultData = {
-      ShopID: this.config !== undefined ? this.config.ShopID : undefined,
-      ShopPass: this.config !== undefined ? this.config.ShopPass : undefined,
+      ShopID: this.config.ShopID,
+      ShopPass: this.config.ShopPass,
       OrderID: undefined,
       Amount: undefined,
       Tax: undefined
@@ -29,7 +23,7 @@ export default class CvsTranable extends Client {
     const data: IEntryTranCvsArgs = merge(defaultData, args)
     const parsed: any = await this.post('/payment/EntryTranCvs.idPass', data)
 
-    return <IEntryTranCvsResult> parsed
+    return <IEntryTranCvsResult>parsed
   }
 
   public async execTranCvs(args: IExecTranCvsArgs): Promise<IExecTranCvsResult> {
@@ -39,7 +33,7 @@ export default class CvsTranable extends Client {
       CustomerKana: encoding.urlEncode(encoding.convert(args.CustomerKana, 'SJIS'))
     })
 
-    return <IExecTranCvsResult> parsed
+    return <IExecTranCvsResult>parsed
   }
 
   public async cancelCvs(args: ICancelCvsArgs): Promise<ICancelCvsResult> {
diff --git a/src/client/memberable.test.ts b/src/client/memberable.test.ts
index f1d0405..012c455 100644
--- a/src/client/memberable.test.ts
+++ b/src/client/memberable.test.ts
@@ -1,6 +1,7 @@
-import anyTest, {TestInterface} from 'ava'
+import test from 'ava'
 import Axios, {AxiosRequestConfig, AxiosResponse} from 'axios'
-import Memberable from './memberable'
+import Client from '../client'
+import WithMemberable from './memberable'
 import {
   IDeleteMemberResult,
   ISaveMemberResult,
@@ -8,20 +9,16 @@ import {
   IUpdateMemberResult
 } from './memberable.interface'
 
-interface Context {
-  member: Memberable
-}
+const Memberable = WithMemberable(Client)
+let member: any
 
-const test = anyTest as TestInterface<Context>;
-
-test.beforeEach((t) => {
-  const member = new Memberable()
+test.beforeEach(() => {
+  member = new Memberable()
   member.client = Axios.create({})
-  t.context.member = member
 })
 
 test('.defaultMemberData returns default object', async (t) => {
-  const res = await t.context.member.defaultMemberData()
+  const res = await member.defaultMemberData()
   const expect = {
     SiteID: undefined,
     SitePass: undefined,
@@ -31,7 +28,7 @@ test('.defaultMemberData returns default object', async (t) => {
 })
 
 test('.saveMember calls API and returns response', async (t) => {
-  t.context.member.options = {
+  member.config.axios = {
     adapter: async (config: AxiosRequestConfig) => {
       const response: AxiosResponse = {
         data: 'MemberID=memberid',
@@ -51,7 +48,7 @@ test('.saveMember calls API and returns response', async (t) => {
     MemberID: 'memberid',
     MemberName: 'membername'
   }
-  const res = await t.context.member.saveMember(args)
+  const res = await member.saveMember(args)
 
   const expect: ISaveMemberResult = {
     MemberID: 'memberid'
@@ -60,7 +57,7 @@ test('.saveMember calls API and returns response', async (t) => {
 })
 
 test('.updateMember calls API and returns response', async (t) => {
-  t.context.member.options = {
+  member.config.axios = {
     adapter: async (config: AxiosRequestConfig) => {
       const response: AxiosResponse = {
         data: 'MemberID=memberid',
@@ -80,7 +77,7 @@ test('.updateMember calls API and returns response', async (t) => {
     MemberID: 'memberid',
     MemberName: 'membername'
   }
-  const res = await t.context.member.updateMember(args)
+  const res = await member.updateMember(args)
 
   const expect: IUpdateMemberResult = {
     MemberID: 'memberid'
@@ -89,7 +86,7 @@ test('.updateMember calls API and returns response', async (t) => {
 })
 
 test('.deleteMember calls API and returns response', async (t) => {
-  t.context.member.options = {
+  member.config.axios = {
     adapter: async (config: AxiosRequestConfig) => {
       const response: AxiosResponse = {
         data: 'MemberID=memberid',
@@ -108,7 +105,7 @@ test('.deleteMember calls API and returns response', async (t) => {
     SitePass: 'sitepass',
     MemberID: 'memberid'
   }
-  const res = await t.context.member.deleteMember(args)
+  const res = await member.deleteMember(args)
 
   const expect: IDeleteMemberResult = {
     MemberID: 'memberid'
@@ -117,7 +114,7 @@ test('.deleteMember calls API and returns response', async (t) => {
 })
 
 test('.searchMember calls API and returns response', async (t) => {
-  t.context.member.options = {
+  member.config.axios = {
     adapter: async (config: AxiosRequestConfig) => {
       const response: AxiosResponse = {
         data: 'MemberID=memberid&MemberName=membername&DeleteFlag=1',
@@ -136,7 +133,7 @@ test('.searchMember calls API and returns response', async (t) => {
     SitePass: 'sitepass',
     MemberID: 'memberid'
   }
-  const res = await t.context.member.searchMember(args)
+  const res = await member.searchMember(args)
 
   const expect: ISearchMemberResult = {
     MemberID: 'memberid',
@@ -147,5 +144,5 @@ test('.searchMember calls API and returns response', async (t) => {
 })
 
 test('.post is function', (t) => {
-  t.is(typeof t.context.member.post, 'function')
+  t.is(typeof member.post, 'function')
 })
diff --git a/src/client/memberable.ts b/src/client/memberable.ts
index 0b25cd4..491abff 100644
--- a/src/client/memberable.ts
+++ b/src/client/memberable.ts
@@ -1,7 +1,6 @@
-import {AxiosInstance} from 'axios'
 import * as merge from 'deepmerge'
 import Client from '../client'
-import {IConfig} from '../config.interface'
+import {Constructor} from '../util'
 import {
   IDeleteMemberArgs,
   IDeleteMemberResult,
@@ -13,24 +12,13 @@ import {
   IUpdateMemberResult
 } from './memberable.interface'
 
-export default class Memberable extends Client {
-  public name: string = 'Memberable'
-  public config: IConfig
-  public client: AxiosInstance
-  public options: object = {}
-
+export default <T extends Constructor<Client>>(Base: T) => class extends Base {
   public defaultMemberData(): any {
-    let siteID
-    let sitePass
-
-    if (this.config !== undefined) {
-      siteID = this.config.SiteID
-      sitePass = this.config.SitePass
-    }
+    const {SiteID, SitePass} = this.config
 
     return {
-      SiteID: siteID,
-      SitePass: sitePass,
+      SiteID,
+      SitePass,
       MemberID: undefined
     }
   }
@@ -39,27 +27,27 @@ export default class Memberable extends Client {
     const data: ISaveMemberArgs = merge(this.defaultMemberData(), args)
     const parsed: any = await this.post('/payment/SaveMember.idPass', data)
 
-    return <ISaveMemberResult> parsed
+    return <ISaveMemberResult>parsed
   }
 
   public async updateMember(args: IUpdateMemberArgs): Promise<IUpdateMemberResult> {
     const data: IUpdateMemberArgs = merge(this.defaultMemberData(), args)
     const parsed: any = await this.post('/payment/UpdateMember.idPass', data)
 
-    return <IUpdateMemberResult> parsed
+    return <IUpdateMemberResult>parsed
   }
 
   public async deleteMember(args: IDeleteMemberArgs): Promise<IDeleteMemberResult> {
     const data: IDeleteMemberArgs = merge(this.defaultMemberData(), args)
     const parsed: any = await this.post('/payment/DeleteMember.idPass', data)
 
-    return <IDeleteMemberResult> parsed
+    return <IDeleteMemberResult>parsed
   }
 
   public async searchMember(args: ISearchMemberArgs): Promise<ISearchMemberResult | null> {
     const data: ISearchMemberArgs = merge(this.defaultMemberData(), args)
     const parsed: any = await this.post('/payment/SearchMember.idPass', data)
 
-    return <ISearchMemberResult> parsed
+    return <ISearchMemberResult>parsed
   }
 }
diff --git a/src/client/multiTranable.test.ts b/src/client/multiTranable.test.ts
index f08b316..6e66fb1 100644
--- a/src/client/multiTranable.test.ts
+++ b/src/client/multiTranable.test.ts
@@ -1,22 +1,23 @@
-import anyTest, {TestInterface} from 'ava'
+import test from 'ava'
 import Axios, {AxiosRequestConfig, AxiosResponse} from 'axios'
 import {CvsCode, PayType, Status, Method, JobCd} from '../client.enum'
-import MultiTranable from './multiTranable'
+import Client from '../client'
+import WithMultiTranable from './multiTranable'
 import {
   ISearchTradeMultiCardResult,
   ISearchTradeMultiCvsResult
 } from './multiTranable.interface'
 
-const test = anyTest as TestInterface<{multiTran: MultiTranable}>;
+const MultiTranable = WithMultiTranable(Client)
+let multiTran: any
 
-test.beforeEach((t) => {
-  const multiTran = new MultiTranable()
+test.beforeEach(() => {
+  multiTran = new MultiTranable()
   multiTran.client = Axios.create({})
-  t.context.multiTran = multiTran
 })
 
 test('.searchTradeMulti calls API and returns response - CVS', async (t) => {
-  t.context.multiTran.options = {
+  multiTran.config.axios = {
     adapter: async (config: AxiosRequestConfig) => {
       const text = [
         `Status=${Status.Reqsuccess}`,
@@ -53,7 +54,7 @@ test('.searchTradeMulti calls API and returns response - CVS', async (t) => {
     OrderID: 'orderid',
     PayType: PayType.Cvs
   }
-  const res = await t.context.multiTran.searchTradeMulti<ISearchTradeMultiCvsResult>(args)
+  const res = await multiTran.searchTradeMulti(args)
 
   const expect: ISearchTradeMultiCvsResult = {
     Status: Status.Reqsuccess,
@@ -76,7 +77,7 @@ test('.searchTradeMulti calls API and returns response - CVS', async (t) => {
 })
 
 test('.searchTradeMulti calls API and returns response - Credit', async (t) => {
-  t.context.multiTran.options = {
+  multiTran.config.axios = {
     adapter: async (config: AxiosRequestConfig) => {
       const text = [
         `Status=${Status.Capture}`,
@@ -119,7 +120,7 @@ test('.searchTradeMulti calls API and returns response - Credit', async (t) => {
     OrderID: 'orderid',
     PayType: PayType.Credit
   }
-  const res = await t.context.multiTran.searchTradeMulti<ISearchTradeMultiCardResult>(args)
+  const res = await multiTran.searchTradeMulti(args)
 
   const expect: ISearchTradeMultiCardResult = {
     Status: Status.Capture,
diff --git a/src/client/multiTranable.ts b/src/client/multiTranable.ts
index 1ddfd80..8a94458 100644
--- a/src/client/multiTranable.ts
+++ b/src/client/multiTranable.ts
@@ -1,31 +1,25 @@
-import {AxiosInstance} from 'axios'
 import * as merge from 'deepmerge'
 import Client from '../client'
-import {IConfig} from '../config.interface'
+import {Constructor} from '../util'
 import {
   ISearchTradeMultiArgs,
   ISearchTradeMultiCardResult,
   ISearchTradeMultiCvsResult
 } from './multiTranable.interface'
 
-export default class MultiTranable extends Client {
-  public name: string = 'MultiTranable'
-  public config: IConfig
-  public client: AxiosInstance
-  public options: object = {}
-
+export default <T extends Constructor<Client>>(Base: T) => class extends Base {
   public async searchTradeMulti<R extends ISearchTradeMultiCardResult | ISearchTradeMultiCvsResult>
     (args: ISearchTradeMultiArgs): Promise<R> {
 
     const defaultData = {
-      ShopID: this.config !== undefined ? this.config.ShopID : undefined,
-      ShopPass: this.config !== undefined ? this.config.ShopPass : undefined,
+      ShopID: this.config.ShopID,
+      ShopPass: this.config.ShopPass,
       OrderID: undefined,
       PayType: undefined
     }
     const data: ISearchTradeMultiArgs = merge(defaultData, args)
     const parsed: any = await this.post('/payment/SearchTradeMulti.idPass', data)
 
-    return <R> parsed
+    return <R>parsed
   }
 }
diff --git a/src/client/tranable.test.ts b/src/client/tranable.test.ts
index 8d7745b..749dccd 100644
--- a/src/client/tranable.test.ts
+++ b/src/client/tranable.test.ts
@@ -1,7 +1,8 @@
-import anyTest, {TestInterface} from 'ava'
+import test from 'ava'
 import Axios, {AxiosRequestConfig, AxiosResponse} from 'axios'
 import {JobCd, Method, Status} from '../client.enum'
-import Tranable from './tranable'
+import Client from '../client'
+import WithTranable from './tranable'
 import {
   IAlterTranResult,
   IChangeTranResult,
@@ -10,20 +11,16 @@ import {
   ISearchTradeResult
 } from './tranable.interface'
 
-interface Context {
-  tran: Tranable
-}
+const Tranable = WithTranable(Client)
+let tran: any
 
-const test = anyTest as TestInterface<Context>;
-
-test.beforeEach((t) => {
-  const tran = new Tranable()
+test.beforeEach(() => {
+  tran = new Tranable()
   tran.client = Axios.create({})
-  t.context.tran = tran
 })
 
 test('.entryTran calls API and returns response', async (t) => {
-  t.context.tran.options = {
+  tran.config.axios = {
     adapter: async (config: AxiosRequestConfig) => {
       const response: AxiosResponse = {
         data: 'AccessID=accessid&AccessPass=accesspass',
@@ -47,7 +44,7 @@ test('.entryTran calls API and returns response', async (t) => {
     JobCd: JobCd.Check,
     Amount: 1234
   }
-  const res = await t.context.tran.entryTran(args)
+  const res = await tran.entryTran(args)
 
   const expect: IEntryTranResult = {
     AccessID: 'accessid',
@@ -57,7 +54,7 @@ test('.entryTran calls API and returns response', async (t) => {
 })
 
 test('.execTran calls API and returns response', async (t) => {
-  t.context.tran.options = {
+  tran.config.axios = {
     adapter: async (config: AxiosRequestConfig) => {
       const text = [
         'Acs=acs',
@@ -95,7 +92,7 @@ test('.execTran calls API and returns response', async (t) => {
     Expire: 'expire',
     SecurityCode: '123'
   }
-  const res = await t.context.tran.execTran(args)
+  const res = await tran.execTran(args)
 
   const expect: IExecTranResult = {
     Acs: 'acs',
@@ -115,7 +112,7 @@ test('.execTran calls API and returns response', async (t) => {
 })
 
 test('.alterTran calls API and returns response', async (t) => {
-  t.context.tran.options = {
+  tran.config.axios = {
     adapter: async (config: AxiosRequestConfig) => {
       const response: AxiosResponse = {
         data: 'AccessID=accessid&AccessPass=accesspass&Forward=forward&Approve=approve&TranID=tranid&TranDate=trandate',
@@ -136,7 +133,7 @@ test('.alterTran calls API and returns response', async (t) => {
     AccessPass: 'accesspass',
     JobCd: JobCd.Check
   }
-  const res = await t.context.tran.alterTran(args)
+  const res = await tran.alterTran(args)
 
   const expect: IAlterTranResult = {
     AccessID: 'accessid',
@@ -150,7 +147,7 @@ test('.alterTran calls API and returns response', async (t) => {
 })
 
 test('.searchTrade calls API and returns response', async (t) => {
-  t.context.tran.options = {
+  tran.config.axios = {
     adapter: async (config: AxiosRequestConfig) => {
       const text = [
         'OrderID=orderid',
@@ -192,7 +189,7 @@ test('.searchTrade calls API and returns response', async (t) => {
     ShopPass: 'shoppass',
     OrderID: 'orderid'
   }
-  const res = await t.context.tran.searchTrade(args)
+  const res = await tran.searchTrade(args)
 
   const expect: ISearchTradeResult = {
     OrderID: 'orderid',
@@ -221,7 +218,7 @@ test('.searchTrade calls API and returns response', async (t) => {
 })
 
 test('.changeTran calls API and returns response', async (t) => {
-  t.context.tran.options = {
+  tran.config.axios = {
     adapter: async (config: AxiosRequestConfig) => {
       const text = [
         'AccessID=accessid',
@@ -251,7 +248,7 @@ test('.changeTran calls API and returns response', async (t) => {
     JobCd: JobCd.Check,
     Amount: 1234
   }
-  const res = await t.context.tran.changeTran(args)
+  const res = await tran.changeTran(args)
 
   const expect: IChangeTranResult = {
     AccessID: 'accessid',
diff --git a/src/client/tranable.ts b/src/client/tranable.ts
index 6228918..6f0269e 100644
--- a/src/client/tranable.ts
+++ b/src/client/tranable.ts
@@ -1,7 +1,6 @@
-import {AxiosInstance} from 'axios'
 import * as merge from 'deepmerge'
 import Client from '../client'
-import {IConfig} from '../config.interface'
+import {Constructor} from '../util'
 import {
   IAlterTranArgs,
   IAlterTranResult,
@@ -15,16 +14,11 @@ import {
   ISearchTradeResult
 } from './tranable.interface'
 
-export default class Tranable extends Client {
-  public name: string = 'Tranable'
-  public config: IConfig
-  public client: AxiosInstance
-  public options: object = {}
-
+export default <T extends Constructor<Client>>(Base: T) => class extends Base {
   public async entryTran(args: IEntryTranArgs): Promise<IEntryTranResult> {
     const defaultData = {
-      ShopID: this.config !== undefined ? this.config.ShopID : undefined,
-      ShopPass: this.config !== undefined ? this.config.ShopPass : undefined,
+      ShopID: this.config.ShopID,
+      ShopPass: this.config.ShopPass,
       OrderID: undefined,
       JobCd: undefined,
       Amount: undefined
@@ -32,19 +26,19 @@ export default class Tranable extends Client {
     const data: IEntryTranArgs = merge(defaultData, args)
     const parsed: any = await this.post('/payment/EntryTran.idPass', data)
 
-    return <IEntryTranResult> parsed
+    return <IEntryTranResult>parsed
   }
 
   public async execTran(args: IExecTranArgs): Promise<IExecTranResult> {
     const parsed: any = await this.post('/payment/ExecTran.idPass', args)
 
-    return <IExecTranResult> parsed
+    return <IExecTranResult>parsed
   }
 
   public async alterTran(args: IAlterTranArgs): Promise<IAlterTranResult> {
-    const defaultData =  {
-      ShopID: this.config !== undefined ? this.config.ShopID : undefined,
-      ShopPass: this.config !== undefined ? this.config.ShopPass : undefined,
+    const defaultData = {
+      ShopID: this.config.ShopID,
+      ShopPass: this.config.ShopPass,
       AccessID: undefined,
       AccessPass: undefined,
       JobCd: undefined
@@ -52,25 +46,25 @@ export default class Tranable extends Client {
     const data: IAlterTranArgs = merge(defaultData, args)
     const parsed: any = await this.post('/payment/AlterTran.idPass', data)
 
-    return <IAlterTranResult> parsed
+    return <IAlterTranResult>parsed
   }
 
   public async searchTrade(args: ISearchTradeArgs): Promise<ISearchTradeResult> {
     const defaultData = {
-      ShopID: this.config !== undefined ? this.config.ShopID : undefined,
-      ShopPass: this.config !== undefined ? this.config.ShopPass : undefined,
+      ShopID: this.config.ShopID,
+      ShopPass: this.config.ShopPass,
       OrderID: undefined
     }
     const data: ISearchTradeArgs = merge(defaultData, args)
     const parsed: any = await this.post('/payment/SearchTrade.idPass', data)
 
-    return <ISearchTradeResult> parsed
+    return <ISearchTradeResult>parsed
   }
 
   public async changeTran(args: IChangeTranArgs): Promise<IChangeTranResult> {
     const defaultData = {
-      ShopID: this.config !== undefined ? this.config.ShopID : undefined,
-      ShopPass: this.config !== undefined ? this.config.ShopPass : undefined,
+      ShopID: this.config.ShopID,
+      ShopPass: this.config.ShopPass,
       AccessID: undefined,
       AccessPass: undefined,
       JobCd: undefined,
@@ -79,6 +73,6 @@ export default class Tranable extends Client {
     const data: IChangeTranArgs = merge(defaultData, args)
     const parsed: any = await this.post('/payment/ChangeTran.idPass', data)
 
-    return <IChangeTranResult> parsed
+    return <IChangeTranResult>parsed
   }
 }
diff --git a/src/gmopg.test.ts b/src/gmopg.test.ts
index e27e525..7243e59 100644
--- a/src/gmopg.test.ts
+++ b/src/gmopg.test.ts
@@ -1,14 +1,10 @@
-import anyTest, {TestInterface} from 'ava'
-import GMOPG from './gmopg'
+import test from 'ava'
+import GMOPG, {ENUMS, GENERATE_MEMBER_ID} from './gmopg'
 
-interface Context {
-  gmopg: GMOPG
-}
+let gmopg: any
 
-const test = anyTest as TestInterface<Context>;
-
-test.beforeEach((t) => {
-  t.context.gmopg = new GMOPG()
+test.beforeEach(() => {
+  gmopg = new GMOPG()
 })
 
 test('constructor.name returns Object', (t) => {
@@ -16,11 +12,11 @@ test('constructor.name returns Object', (t) => {
 })
 
 test('new returns GMOPG instance', (t) => {
-  t.true(t.context.gmopg instanceof GMOPG)
+  t.true(gmopg instanceof GMOPG)
 })
 
 test('.ENUMS returns enum object', (t) => {
-  t.deepEqual(Object.keys(GMOPG.ENUMS), [
+  t.deepEqual(Object.keys(ENUMS), [
     'PayType',
     'Method',
     'Status',
@@ -31,18 +27,13 @@ test('.ENUMS returns enum object', (t) => {
   ])
 })
 
-test('.CREATE returns new GMOPG instance', (t) => {
-  const instance = GMOPG.CREATE()
-  t.true(instance instanceof GMOPG)
-})
-
 test('.GENERATE_MEMBER_ID returns generated memberID', (t) => {
-  const ID = GMOPG.GENERATE_MEMBER_ID('key')
+  const ID = GENERATE_MEMBER_ID('key')
   t.regex(ID, /^key-\w{32}$/)
 })
 
 test('.GENERATE_MEMBER_ID returns max 60 chars', (t) => {
-  const ID = GMOPG.GENERATE_MEMBER_ID('0123456789-0123456789-0123456789-0123456789')
+  const ID = GENERATE_MEMBER_ID('0123456789-0123456789-0123456789-0123456789')
   t.regex(ID, /^.{60}$/)
 })
 
@@ -56,77 +47,77 @@ test('.config returns IConfig', (t) => {
       }
     }
   }
-  t.deepEqual(t.context.gmopg.config, expect)
+  t.deepEqual(gmopg.config, expect)
 })
 
 test('.client returns AxiosInstance', (t) => {
-  t.is(typeof t.context.gmopg.client, 'function')
+  t.is(typeof gmopg.client, 'function')
 })
 
 test('.saveMember is function', (t) => {
-  t.is(typeof t.context.gmopg.saveMember, 'function')
+  t.is(typeof gmopg.saveMember, 'function')
 })
 
 test('.updateMember is function', (t) => {
-  t.is(typeof t.context.gmopg.updateMember, 'function')
+  t.is(typeof gmopg.updateMember, 'function')
 })
 
 test('.deleteMember is function', (t) => {
-  t.is(typeof t.context.gmopg.deleteMember, 'function')
+  t.is(typeof gmopg.deleteMember, 'function')
 })
 
 test('.searchMember is function', (t) => {
-  t.is(typeof t.context.gmopg.searchMember, 'function')
+  t.is(typeof gmopg.searchMember, 'function')
 })
 
 test('.saveCard is function', (t) => {
-  t.is(typeof t.context.gmopg.saveCard, 'function')
+  t.is(typeof gmopg.saveCard, 'function')
 })
 
 test('.deleteCard is function', (t) => {
-  t.is(typeof t.context.gmopg.deleteCard, 'function')
+  t.is(typeof gmopg.deleteCard, 'function')
 })
 
 test('.searchCard is function', (t) => {
-  t.is(typeof t.context.gmopg.searchCard, 'function')
+  t.is(typeof gmopg.searchCard, 'function')
 })
 
 test('.entryTran is function', (t) => {
-  t.is(typeof t.context.gmopg.entryTran, 'function')
+  t.is(typeof gmopg.entryTran, 'function')
 })
 
 test('.execTran is function', (t) => {
-  t.is(typeof t.context.gmopg.execTran, 'function')
+  t.is(typeof gmopg.execTran, 'function')
 })
 
 test('.alterTran is function', (t) => {
-  t.is(typeof t.context.gmopg.alterTran, 'function')
+  t.is(typeof gmopg.alterTran, 'function')
 })
 
 test('.searchTrade is function', (t) => {
-  t.is(typeof t.context.gmopg.searchTrade, 'function')
+  t.is(typeof gmopg.searchTrade, 'function')
 })
 
 test('.changeTran is function', (t) => {
-  t.is(typeof t.context.gmopg.changeTran, 'function')
+  t.is(typeof gmopg.changeTran, 'function')
 })
 
 test('.entryTranCvs is function', (t) => {
-  t.is(typeof t.context.gmopg.entryTranCvs, 'function')
+  t.is(typeof gmopg.entryTranCvs, 'function')
 })
 
 test('.execTranCvs is function', (t) => {
-  t.is(typeof t.context.gmopg.execTranCvs, 'function')
+  t.is(typeof gmopg.execTranCvs, 'function')
 })
 
 test('.cancelCvs is function', (t) => {
-  t.is(typeof t.context.gmopg.cancelCvs, 'function')
+  t.is(typeof gmopg.cancelCvs, 'function')
 })
 
 test('.searchTradeMulti is function', (t) => {
-  t.is(typeof t.context.gmopg.searchTradeMulti, 'function')
+  t.is(typeof gmopg.searchTradeMulti, 'function')
 })
 
 test('.post is function', (t) => {
-  t.is(typeof t.context.gmopg.post, 'function')
+  t.is(typeof gmopg.post, 'function')
 })
diff --git a/src/gmopg.ts b/src/gmopg.ts
index 274b6ba..d0676b4 100644
--- a/src/gmopg.ts
+++ b/src/gmopg.ts
@@ -1,122 +1,19 @@
-import Axios, {AxiosInstance} from 'axios'
-import * as merge from 'deepmerge'
 import * as enums from './client.enum'
-import Memberable from './client/memberable'
-import Cardable from './client/cardable'
-import Tranable from './client/tranable'
-import CvsTranable from './client/cvsTranable'
-import MultiTranable from './client/multiTranable'
-import {buildByEnv, defaults} from './config'
-import {applyMixins, generateID} from './util'
-import {IConfig} from './config.interface'
-import {
-  IDeleteMemberArgs,
-  IDeleteMemberResult,
-  ISaveMemberArgs,
-  ISaveMemberResult,
-  ISearchMemberArgs,
-  ISearchMemberResult,
-  IUpdateMemberArgs,
-  IUpdateMemberResult
-} from './client/memberable.interface'
-import {
-  IDeleteCardArgs,
-  IDeleteCardResult,
-  ISaveCardArgs,
-  ISaveCardResult,
-  ISearchCardArgs,
-  ISearchCardResult
-} from './client/cardable.interface'
-import {
-  IAlterTranArgs,
-  IAlterTranResult,
-  IChangeTranArgs,
-  IChangeTranResult,
-  IEntryTranArgs,
-  IEntryTranResult,
-  IExecTranArgs,
-  IExecTranResult,
-  ISearchTradeArgs,
-  ISearchTradeResult
-} from './client/tranable.interface'
-import {
-  ICancelCvsArgs,
-  ICancelCvsResult,
-  IEntryTranCvsArgs,
-  IEntryTranCvsResult,
-  IExecTranCvsArgs,
-  IExecTranCvsResult
-} from './client/cvsTranable.interface'
-import {
-  ISearchTradeMultiArgs,
-  ISearchTradeMultiCardResult,
-  ISearchTradeMultiCvsResult
-} from './client/multiTranable.interface'
-
-export class GMOPG implements Memberable, Cardable, Tranable, CvsTranable, MultiTranable {
-  public name: string = 'GMOPG'
-  public client: AxiosInstance
-  public options: object
-  public config: IConfig
-
-  // client
-  public post: (endpoint: string, data: any) => Promise<any>
-  public isError: (res: any) => boolean
-
-  // memberable
-  public defaultMemberData: () => any
-  public saveMember: (args: ISaveMemberArgs) => Promise<ISaveMemberResult>
-  public updateMember: (args: IUpdateMemberArgs) => Promise<IUpdateMemberResult>
-  public deleteMember: (args: IDeleteMemberArgs) => Promise<IDeleteMemberResult>
-  public searchMember: (args: ISearchMemberArgs) => Promise<ISearchMemberResult | null>
-
-  // cardable
-  public defaultCardData: () => any
-  public saveCard: (args: ISaveCardArgs) => Promise<ISaveCardResult>
-  public deleteCard: (args: IDeleteCardArgs) => Promise<IDeleteCardResult>
-  public searchCard: (args: ISearchCardArgs) => Promise<ISearchCardResult[]>
-
-  // tranable
-  public entryTran: (args: IEntryTranArgs) => Promise<IEntryTranResult>
-  public execTran: (args: IExecTranArgs) => Promise<IExecTranResult>
-  public alterTran: (args: IAlterTranArgs) => Promise<IAlterTranResult>
-  public searchTrade: (args: ISearchTradeArgs) => Promise<ISearchTradeResult>
-  public changeTran: (args: IChangeTranArgs) => Promise<IChangeTranResult>
-
-  // tranable - cvs
-  public entryTranCvs: (args: IEntryTranCvsArgs) => Promise<IEntryTranCvsResult>
-  public execTranCvs: (args: IExecTranCvsArgs) => Promise<IExecTranCvsResult>
-  public cancelCvs: (args: ICancelCvsArgs) => Promise<ICancelCvsResult>
-
-  // tranable - multi
-  public searchTradeMulti: <R extends ISearchTradeMultiCardResult | ISearchTradeMultiCvsResult>(args: ISearchTradeMultiArgs) => Promise<R>
-
-  constructor(config?: IConfig) {
-    if (config === undefined) {
-      config = {}
-    }
-    this.config = merge(defaults, config)
-    const configByEnv: IConfig = buildByEnv()
-    if (configByEnv !== {}) {
-      this.config = merge(this.config, configByEnv)
-    }
-    this.client = Axios.create(this.config.axios)
-  }
-
-  public static CREATE(config?: IConfig): GMOPG {
-    return new GMOPG(config)
-  }
-
-  public static GENERATE_MEMBER_ID(key: string): string {
-    return generateID(key).substring(0, 60)
-  }
-
-  public static get ENUMS() {
-    return enums
-  }
+import WithMemberable from './client/memberable'
+import WithCardable from './client/cardable'
+import WithTranable from './client/tranable'
+import WithCvsTranable from './client/cvsTranable'
+import WithMultiTranable from './client/multiTranable'
+import {generateID} from './util'
+import Client from './client'
+
+export default WithCardable(WithCvsTranable(WithMemberable(WithMultiTranable(WithTranable(Client)))))
+
+export function GENERATE_MEMBER_ID(key: string): string {
+  return generateID(key).substring(0, 60)
 }
 
-applyMixins(GMOPG, [Memberable, Cardable, Tranable, CvsTranable, MultiTranable])
+export {enums as ENUMS}
 
 export * from './config.interface'
 export * from './client.interface'
@@ -126,4 +23,3 @@ export * from './client/cardable.interface'
 export * from './client/tranable.interface'
 export * from './client/cvsTranable.interface'
 export * from './client/multiTranable.interface'
-export default GMOPG
diff --git a/src/util.test.ts b/src/util.test.ts
index 071fa6a..5c85385 100644
--- a/src/util.test.ts
+++ b/src/util.test.ts
@@ -1,40 +1,8 @@
 import test from 'ava'
 import * as Util from './util'
 
-class Brand {
-  public sign() {
-  }
-}
-
-class Tire extends Brand {
-  public rollTire() {
-  }
-}
-
-class Engine extends Brand {
-  public startEngine() {
-  }
-}
-
-class Car implements Tire, Engine {
-  public sign: () => void
-  public rollTire: () => void
-  public startEngine: () => void
-}
-
-Util.applyMixins(Car, [Tire, Engine])
-
-test('.applyMixins mixes other methods', (t) => {
-  const car = new Car()
-  t.is(typeof car.rollTire, 'function')
-  t.is(typeof car.startEngine, 'function')
-})
-
-test('.applyMixins mixes prototype chain method', (t) => {
-  const car = new Car()
-  t.is(typeof car.sign, 'function')
-})
-
 test('.generateID returns key with hash', (t) => {
   t.regex(Util.generateID('foo'), /foo-\w{32}/)
 })
+
+
diff --git a/src/util.ts b/src/util.ts
index 0c7fad3..2ed1c4a 100644
--- a/src/util.ts
+++ b/src/util.ts
@@ -1,20 +1,7 @@
 import {createHash} from 'crypto'
 
-export function applyMixins(derivedCtor: any, baseCtors: any[]) {
-  baseCtors.forEach((baseCtor) => {
-    Object.getOwnPropertyNames(baseCtor.prototype.__proto__).forEach((name) => {
-      if (name !== 'constructor') {
-        derivedCtor.prototype[name] = baseCtor.prototype[name]
-      }
-    })
-    Object.getOwnPropertyNames(baseCtor.prototype).forEach((name) => {
-      if (name !== 'constructor') {
-        derivedCtor.prototype[name] = baseCtor.prototype[name]
-      }
-    })
-  })
-}
-
 export function generateID(key: string): string {
   return `${key}-${createHash('md5').update(`${key}-${new Date().toISOString()}`).digest('hex')}`
 }
+
+export type Constructor<T> = new (...args: any[]) => T;
diff --git a/tslint.json b/tslint.json
index 2a1cd5c..e5ce4c6 100644
--- a/tslint.json
+++ b/tslint.json
@@ -40,7 +40,8 @@
       "parameter",
       "property-declaration",
       "member-variable-declaration"
-    ]
+    ],
+    "variable-name": [true, "allow-pascal-case"]
   },
   "linterOptions": {
     "exclude": [