diff --git a/src/adpater/createAdapter.ts b/src/adpater/createAdapter.ts
index 192343b..9bddaec 100644
--- a/src/adpater/createAdapter.ts
+++ b/src/adpater/createAdapter.ts
@@ -140,11 +140,11 @@ export interface AxiosAdapterBaseOptions extends AxiosAdapterRequestConfig {
   /**
    * 成功的回调
    */
-  success(response: AxiosAdapterResponse): void;
+  success(response: AnyObject): void;
   /**
    * 失败的回调
    */
-  fail(error: AxiosAdapterResponseError): void;
+  fail(error: AnyObject): void;
 }
 
 /**
@@ -271,11 +271,11 @@ export function createAdapter(platform: AxiosAdapterPlatform) {
     return {
       ...config,
       header: config.headers,
-      success(response) {
+      success(response: AxiosAdapterResponse) {
         transformResponse(response);
         config.success(response);
       },
-      fail(responseError) {
+      fail(responseError: AxiosAdapterResponseError) {
         responseError.data = {
           errMsg: responseError.errMsg,
           errno: responseError.errno,
@@ -284,14 +284,14 @@ export function createAdapter(platform: AxiosAdapterPlatform) {
         config.fail(responseError);
       },
     };
+  }
 
-    function transformResponse(
-      response: AxiosAdapterResponse | AxiosAdapterResponseError,
-    ) {
-      response.status = response.status ?? response.statusCode;
-      response.headers = response.headers ?? response.header;
-      clean(response, ['statusCode', 'errMsg', 'errno', 'header']);
-    }
+  function transformResponse(
+    response: AxiosAdapterResponse | AxiosAdapterResponseError,
+  ) {
+    response.status = response.status ?? response.statusCode;
+    response.headers = response.headers ?? response.header;
+    clean(response, ['statusCode', 'errMsg', 'errno', 'header']);
   }
 
   function processRequest(
diff --git a/src/axios.ts b/src/axios.ts
index 4d55c38..5811d04 100644
--- a/src/axios.ts
+++ b/src/axios.ts
@@ -4,37 +4,13 @@ import {
   isCancel,
 } from './request/cancel';
 import { isAxiosError } from './request/createError';
+import Axios, { AxiosConstructor, AxiosRequestConfig } from './core/Axios';
+import { AxiosInstance, createInstance } from './core/createInstance';
 import { mergeConfig } from './core/mergeConfig';
-import { AxiosDomainRequest } from './core/AxiosDomain';
-import Axios, {
-  AxiosConstructor,
-  AxiosRequestConfig,
-  AxiosRequestHeaders,
-} from './core/Axios';
 import { createAdapter } from './adpater/createAdapter';
 import defaults from './defaults';
 import { version } from './version';
 
-/**
- * axios 实例默认配置
- */
-export interface AxiosInstanceDefaults extends AxiosRequestConfig {
-  /**
-   * 请求头
-   */
-  headers: Required<AxiosRequestHeaders>;
-}
-
-/**
- * axios 实例
- */
-export interface AxiosInstance extends AxiosDomainRequest, Axios {
-  /**
-   * 默认请求配置
-   */
-  defaults: AxiosInstanceDefaults;
-}
-
 /**
  * axios 静态对象
  */
@@ -51,12 +27,6 @@ export interface AxiosStatic extends AxiosInstance {
    * 取消令牌
    */
   CancelToken: CancelTokenConstructor;
-  /**
-   * 创建 axios 实例
-   *
-   * @param config 默认配置
-   */
-  create(config?: AxiosRequestConfig): AxiosInstance;
   /**
    * 创建适配器
    */
@@ -69,26 +39,18 @@ export interface AxiosStatic extends AxiosInstance {
    * 传入响应错误返回 true
    */
   isAxiosError: typeof isAxiosError;
-}
-
-function createInstance(config: AxiosRequestConfig) {
-  const context = new Axios(config);
-  const instance = context.request as AxiosInstance;
-
-  Object.assign(instance, context);
-  Object.setPrototypeOf(instance, Axios.prototype);
-
-  return instance;
+  /**
+   * 创建 axios 实例
+   *
+   * @param config 默认配置
+   */
+  create(config?: AxiosRequestConfig): AxiosInstance;
 }
 
 const axios = createInstance(defaults) as AxiosStatic;
-
 axios.create = function create(config) {
-  const instance = createInstance(mergeConfig(axios.defaults, config));
-  instance.flush = axios.middleware.wrap(instance.flush);
-  return instance;
+  return createInstance(mergeConfig(axios.defaults, config));
 };
-
 axios.version = version;
 axios.Axios = Axios;
 axios.CancelToken = CancelToken;
diff --git a/src/core/Axios.ts b/src/core/Axios.ts
index dfbdf32..415ccd8 100644
--- a/src/core/Axios.ts
+++ b/src/core/Axios.ts
@@ -1,7 +1,9 @@
-import { buildURL } from '../helpers/buildURL';
 import { combineURL } from '../helpers/combineURL';
+import { isString } from '../helpers/isTypes';
+import { dispatchRequest } from '../request/dispatchRequest';
 import { CancelToken } from '../request/cancel';
 import { AxiosTransformer } from '../request/transformData';
+import { deepMerge } from '../helpers/deepMerge';
 import {
   AxiosAdapter,
   AxiosAdapterRequestMethod,
@@ -9,9 +11,17 @@ import {
   AxiosAdapterRequestConfig,
   AxiosAdapterResponseData,
 } from '../adpater/createAdapter';
-import InterceptorManager, { Interceptor } from './InterceptorManager';
+import InterceptorManager, {
+  Interceptor,
+  InterceptorExecutor,
+} from './InterceptorManager';
 import { mergeConfig } from './mergeConfig';
-import AxiosDomain, { AxiosDomainRequestHandler } from './AxiosDomain';
+import {
+  PLAIN_METHODS,
+  WITH_DATA_METHODS,
+  WITH_PARAMS_METHODS,
+} from '../constants/methods';
+import MiddlewareManager from './MiddlewareManager';
 
 /**
  * 请求方法
@@ -293,6 +303,51 @@ export interface AxiosResponseError extends AnyObject {
   request?: AxiosAdapterPlatformTask;
 }
 
+export interface AxiosContext {
+  req: AxiosRequestConfig;
+  res: null | AxiosResponse;
+}
+
+export interface AxiosRequest {
+  <TData extends AxiosResponseData>(config: AxiosRequestConfig): Promise<
+    AxiosResponse<TData>
+  >;
+  <TData extends AxiosResponseData>(
+    url: string,
+    config?: AxiosRequestConfig,
+  ): Promise<AxiosResponse<TData>>;
+}
+
+/**
+ * 普通的请求方法
+ */
+export type AxiosRequestMethodFn = <TData extends AxiosResponseData>(
+  url: string,
+  config?: AxiosRequestConfig,
+) => Promise<AxiosResponse<TData>>;
+
+/**
+ * 带参数的请求方法
+ */
+export type AxiosRequestMethodFnWithParams = <TData extends AxiosResponseData>(
+  url: string,
+  params?: AnyObject,
+  config?: AxiosRequestConfig,
+) => Promise<AxiosResponse<TData>>;
+
+/**
+ * 带数据的请求方法
+ */
+export type AxiosRequestMethodFnWithData = <TData extends AxiosResponseData>(
+  url: string,
+  data?: AxiosRequestData,
+  config?: AxiosRequestConfig,
+) => Promise<AxiosResponse<TData>>;
+
+export interface AxiosDomainRequestHandler {
+  (config: AxiosRequestConfig): Promise<AxiosResponse>;
+}
+
 /**
  * Axios 构造函数
  */
@@ -300,7 +355,13 @@ export interface AxiosConstructor {
   new (config: AxiosRequestConfig): Axios;
 }
 
-export default class Axios extends AxiosDomain {
+export default class Axios {
+  #parent?: Axios;
+  /**
+   * 默认请求配置
+   */
+  defaults: AxiosRequestConfig;
+
   /**
    * 拦截器
    */
@@ -315,37 +376,102 @@ export default class Axios extends AxiosDomain {
     response: new InterceptorManager<AxiosResponse>(),
   };
 
-  constructor(defaults: AxiosRequestConfig = {}) {
-    super(defaults, (...args) => this.#processRequest(...args));
-  }
+  /**
+   * 中间件
+   */
+  #middleware = new MiddlewareManager<AxiosContext>(async (ctx) => {
+    ctx.res = await dispatchRequest(ctx.req);
+  });
 
-  getUri(config: AxiosRequestConfig): string {
-    const { url, params, paramsSerializer } = mergeConfig(
-      this.defaults,
-      config,
-    );
-    return buildURL(url, params, paramsSerializer).replace(/^\?/, '');
+  /**
+   * 发送 options 请求
+   */
+  options!: AxiosRequestMethodFn;
+
+  /**
+   * 发送 get 请求
+   */
+  get!: AxiosRequestMethodFnWithParams;
+
+  /**
+   * 发送 head 请求
+   */
+  head!: AxiosRequestMethodFnWithParams;
+
+  /**
+   * 发送 post 请求
+   */
+  post!: AxiosRequestMethodFnWithData;
+
+  /**
+   * 发送 put 请求
+   */
+  put!: AxiosRequestMethodFnWithData;
+
+  /**
+   * 发送 patch 请求
+   */
+  patch!: AxiosRequestMethodFnWithData;
+
+  /**
+   * 发送 delete 请求
+   */
+  delete!: AxiosRequestMethodFnWithParams;
+
+  /**
+   * 发送 trace 请求
+   */
+  trace!: AxiosRequestMethodFn;
+
+  /**
+   * 发送 connect 请求
+   */
+  connect!: AxiosRequestMethodFn;
+
+  /**
+   * 添加中间件
+   */
+  use: MiddlewareManager<AxiosContext>['use'];
+
+  constructor(defaults: AxiosRequestConfig = {}, parent?: Axios) {
+    this.defaults = defaults;
+    this.#parent = parent;
+    if (this.#parent) {
+      this.#middleware.flush = this.#parent.#middleware.wrap(
+        this.#middleware.flush,
+      );
+    }
+    this.use = this.#middleware.use.bind(this.#middleware);
   }
 
   /**
-   * 派生领域
+   * 发送请求
    */
-  fork = (config: AxiosRequestConfig = {}) => {
-    config.baseURL = combineURL(this.defaults.baseURL, config.baseURL);
-    const domain = new AxiosDomain(
-      mergeConfig(this.defaults, config),
-      (...args) => this.#processRequest(...args),
-    );
-    domain.flush = this.middleware.wrap(domain.flush);
-    return domain;
+  request: AxiosRequest = (
+    urlOrConfig: string | AxiosRequestConfig,
+    config: AxiosRequestConfig = {},
+  ) => {
+    if (isString(urlOrConfig)) {
+      config.url = urlOrConfig;
+    } else {
+      config = urlOrConfig;
+    }
+    config.method = config.method || 'get';
+
+    return this.#processRequest(mergeConfig(this.defaults, config));
   };
 
-  #processRequest(
-    config: AxiosRequestConfig,
-    requestHandlerFn: AxiosDomainRequestHandler,
-  ) {
+  #processRequest(config: AxiosRequestConfig) {
     const requestHandler = {
-      resolved: requestHandlerFn,
+      resolved: async (config: AxiosRequestConfig) => {
+        config.url = combineURL(config.baseURL, config.url);
+        const ctx: AxiosContext = {
+          req: config,
+          res: null,
+        };
+        await this.#middleware.flush(ctx);
+        return ctx.res as AxiosResponse;
+      },
     };
     const errorHandler = {
       rejected: config.errorHandler,
@@ -355,11 +481,11 @@ export default class Axios extends AxiosDomain {
       | Partial<Interceptor<AxiosResponse>>
     )[] = [];
 
-    this.interceptors.request.forEach((requestInterceptor) => {
+    this.#eacheRequestInterceptors((requestInterceptor) => {
       chain.unshift(requestInterceptor);
     });
     chain.push(requestHandler);
-    this.interceptors.response.forEach((responseInterceptor) => {
+    this.#eacheResponseInterceptors((responseInterceptor) => {
       chain.push(responseInterceptor);
     });
     chain.push(errorHandler);
@@ -374,4 +500,49 @@ export default class Axios extends AxiosDomain {
       Promise.resolve(config),
     ) as Promise<AxiosResponse>;
   }
+
+  #eacheRequestInterceptors(executor: InterceptorExecutor<AxiosRequestConfig>) {
+    this.interceptors.request.forEach(executor);
+    if (this.#parent) {
+      this.#parent.#eacheRequestInterceptors(executor);
+    }
+  }
+
+  #eacheResponseInterceptors(executor: InterceptorExecutor<AxiosResponse>) {
+    this.interceptors.response.forEach(executor);
+    if (this.#parent) {
+      this.#parent.#eacheResponseInterceptors(executor);
+    }
+  }
+}
+
+for (const method of PLAIN_METHODS) {
+  Axios.prototype[method] = function processRequestMethod(url, config = {}) {
+    config.method = method;
+    return this.request(url, config);
+  };
+}
+
+for (const method of WITH_PARAMS_METHODS) {
+  Axios.prototype[method] = function processRequestMethodWithParams(
+    url,
+    params = {},
+    config = {},
+  ) {
+    config.method = method;
+    config.params = deepMerge(params, config.params ?? {});
+    return this.request(url, config);
+  };
+}
+
+for (const method of WITH_DATA_METHODS) {
+  Axios.prototype[method] = function processRequestMethodWithData(
+    url,
+    data,
+    config = {},
+  ) {
+    config.method = method;
+    config.data = data;
+    return this.request(url, config);
+  };
 }
diff --git a/src/core/AxiosDomain.ts b/src/core/AxiosDomain.ts
deleted file mode 100644
index e631226..0000000
--- a/src/core/AxiosDomain.ts
+++ /dev/null
@@ -1,205 +0,0 @@
-import {
-  PLAIN_METHODS,
-  WITH_DATA_METHODS,
-  WITH_PARAMS_METHODS,
-} from '../constants/methods';
-import { isString, isUndefined } from '../helpers/isTypes';
-import { deepMerge } from '../helpers/deepMerge';
-import { combineURL } from '../helpers/combineURL';
-import { dispatchRequest } from '../request/dispatchRequest';
-import { mergeConfig } from './mergeConfig';
-import {
-  AxiosRequestConfig,
-  AxiosRequestData,
-  AxiosResponse,
-  AxiosResponseData,
-} from './Axios';
-import MiddlewareManager, {
-  MiddlewareContext,
-  MiddlewareFlush,
-} from './MiddlewareManager';
-
-/**
- * 请求函数
- */
-export interface AxiosDomainRequest {
-  <TData extends AxiosResponseData>(config: AxiosRequestConfig): Promise<
-    AxiosResponse<TData>
-  >;
-  <TData extends AxiosResponseData>(
-    url: string,
-    config?: AxiosRequestConfig,
-  ): Promise<AxiosResponse<TData>>;
-}
-
-/**
- * 普通的请求方法
- */
-export type AxiosDomainRequestMethod = <TData extends AxiosResponseData>(
-  url: string,
-  config?: AxiosRequestConfig,
-) => Promise<AxiosResponse<TData>>;
-
-/**
- * 带参数的请求方法
- */
-export type AxiosDomainRequestMethodWithParams = <
-  TData extends AxiosResponseData,
->(
-  url: string,
-  params?: AnyObject,
-  config?: AxiosRequestConfig,
-) => Promise<AxiosResponse<TData>>;
-
-/**
- * 带数据的请求方法
- */
-export type AxiosDomainRequestMethodWithData = <
-  TData extends AxiosResponseData,
->(
-  url: string,
-  data?: AxiosRequestData,
-  config?: AxiosRequestConfig,
-) => Promise<AxiosResponse<TData>>;
-
-export interface AxiosDomainRequestHandler {
-  (config: AxiosRequestConfig): Promise<AxiosResponse>;
-}
-
-export default class AxiosDomain {
-  /**
-   * 默认请求配置
-   */
-  defaults: AxiosRequestConfig;
-
-  middleware = new MiddlewareManager();
-
-  /**
-   * 发送请求
-   */
-  request!: AxiosDomainRequest;
-
-  /**
-   * 发送 options 请求
-   */
-  options!: AxiosDomainRequestMethod;
-
-  /**
-   * 发送 get 请求
-   */
-  get!: AxiosDomainRequestMethodWithParams;
-
-  /**
-   * 发送 head 请求
-   */
-  head!: AxiosDomainRequestMethodWithParams;
-
-  /**
-   * 发送 post 请求
-   */
-  post!: AxiosDomainRequestMethodWithData;
-
-  /**
-   * 发送 put 请求
-   */
-  put!: AxiosDomainRequestMethodWithData;
-
-  /**
-   * 发送 patch 请求
-   */
-  patch!: AxiosDomainRequestMethodWithData;
-
-  /**
-   * 发送 delete 请求
-   */
-  delete!: AxiosDomainRequestMethodWithParams;
-
-  /**
-   * 发送 trace 请求
-   */
-  trace!: AxiosDomainRequestMethod;
-
-  /**
-   * 发送 connect 请求
-   */
-  connect!: AxiosDomainRequestMethod;
-
-  flush: MiddlewareFlush;
-
-  constructor(
-    defaults: AxiosRequestConfig,
-    processRequest: (
-      config: AxiosRequestConfig,
-      requestHandler: AxiosDomainRequestHandler,
-    ) => Promise<AxiosResponse>,
-  ) {
-    this.defaults = defaults;
-
-    this.request = (
-      urlOrConfig: string | AxiosRequestConfig,
-      config: AxiosRequestConfig = {},
-    ) => {
-      if (isString(urlOrConfig)) {
-        config.url = urlOrConfig;
-      } else {
-        config = urlOrConfig;
-      }
-
-      if (isUndefined(config.method)) {
-        config.method = 'get';
-      }
-
-      return processRequest(
-        mergeConfig(this.defaults, config),
-        this.#requestHandler,
-      );
-    };
-    this.flush = this.middleware.wrap(async (ctx) => {
-      ctx.res = await dispatchRequest(ctx.req);
-    });
-  }
-
-  #requestHandler: AxiosDomainRequestHandler = async (config) => {
-    config.url = combineURL(config.baseURL, config.url);
-    const ctx: MiddlewareContext = {
-      req: config,
-      res: null,
-    };
-    await this.flush(ctx);
-    return ctx.res as AxiosResponse;
-  };
-}
-
-for (const method of PLAIN_METHODS) {
-  AxiosDomain.prototype[method] = function processRequestMethod(
-    url,
-    config = {},
-  ) {
-    config.method = method;
-    return this.request(url, config);
-  };
-}
-
-for (const method of WITH_PARAMS_METHODS) {
-  AxiosDomain.prototype[method] = function processRequestMethodWithParams(
-    url,
-    params = {},
-    config = {},
-  ) {
-    config.method = method;
-    config.params = deepMerge(params, config.params ?? {});
-    return this.request(url, config);
-  };
-}
-
-for (const method of WITH_DATA_METHODS) {
-  AxiosDomain.prototype[method] = function processRequestMethodWithData(
-    url,
-    data,
-    config = {},
-  ) {
-    config.method = method;
-    config.data = data;
-    return this.request(url, config);
-  };
-}
diff --git a/src/core/MiddlewareManager.ts b/src/core/MiddlewareManager.ts
index c669bf9..527d339 100644
--- a/src/core/MiddlewareManager.ts
+++ b/src/core/MiddlewareManager.ts
@@ -1,36 +1,44 @@
 import { assert } from '../helpers/error';
 import { combineURL } from '../helpers/combineURL';
-import { isFunction } from '../helpers/isTypes';
-import { AxiosRequestConfig, AxiosResponse } from './Axios';
-
-export interface MiddlewareContext {
-  req: AxiosRequestConfig;
-  res: null | AxiosResponse;
-}
+import { isFunction, isString } from '../helpers/isTypes';
 
 export interface MiddlewareNext {
   (): Promise<void>;
 }
 
-export interface MiddlewareCallback {
-  (ctx: MiddlewareContext, next: MiddlewareNext): Promise<void>;
+export interface MiddlewareCallback<Conext extends AnyObject> {
+  (ctx: Conext, next: MiddlewareNext): Promise<void>;
 }
 
-export interface MiddlewareFlush {
-  (ctx: MiddlewareContext): Promise<void>;
+export interface MiddlewareFlush<Conext extends AnyObject> {
+  (ctx: Conext): Promise<void>;
 }
 
-export default class MiddlewareManager {
-  #map = new Map<string, MiddlewareCallback[]>();
+export default class MiddlewareManager<Conext extends AnyObject = AnyObject> {
+  #map = new Map<string, MiddlewareCallback<Conext>[]>();
 
-  use(callback: MiddlewareCallback): MiddlewareManager;
-  use(path: string, callback: MiddlewareCallback): MiddlewareManager;
-  use(path: string | MiddlewareCallback, callback?: MiddlewareCallback) {
+  flush: MiddlewareFlush<Conext>;
+
+  constructor(flush: MiddlewareFlush<Conext>) {
+    this.flush = this.wrap(flush);
+  }
+
+  use(callback: MiddlewareCallback<Conext>): MiddlewareManager<Conext>;
+  use(
+    path: string,
+    callback: MiddlewareCallback<Conext>,
+  ): MiddlewareManager<Conext>;
+  use(
+    path: string | MiddlewareCallback<Conext>,
+    callback?: MiddlewareCallback<Conext>,
+  ) {
     if (isFunction(path)) {
       callback = path;
       path = '/';
     }
-    assert(!!path, 'path 不是一个非空的 string');
+    assert(isString(path), 'path 不是一个 string');
+    assert(!!path, 'path 不是一个长度大于零的 string');
+    assert(isFunction(callback), 'callback 不是一个 function');
 
     const middlewares = this.#map.get(path) ?? [];
     middlewares.push(callback!);
@@ -39,32 +47,25 @@ export default class MiddlewareManager {
     return this;
   }
 
-  wrap(flush: MiddlewareFlush): MiddlewareFlush {
-    return (ctx) => this.#performer(ctx, flush);
-  }
+  wrap(flush: MiddlewareFlush<Conext>): MiddlewareFlush<Conext> {
+    return (ctx) => {
+      const allMiddlewares: MiddlewareCallback<Conext>[] = [];
 
-  #performer(ctx: MiddlewareContext, flush: MiddlewareFlush) {
-    const middlewares = [...this.#getAllMiddlewares(ctx), flush];
+      for (const [path, middlewares] of this.#map.entries()) {
+        const url = combineURL(ctx.req.baseURL, path);
+        const checkRE = new RegExp(`^${url}([/?].*)?`);
 
-    function next(): Promise<void> {
-      return middlewares.shift()!(ctx, next);
-    }
-
-    return next();
-  }
-
-  #getAllMiddlewares(ctx: MiddlewareContext) {
-    const allMiddlewares: MiddlewareCallback[] = [];
-
-    for (const [path, middlewares] of this.#map.entries()) {
-      const url = combineURL(ctx.req.baseURL, path);
-
-      const checkRE = new RegExp(`^${url}([/?].*)?`);
-      if (checkRE.test(ctx.req.url!)) {
-        allMiddlewares.push(...middlewares);
+        if (path === '/') {
+          allMiddlewares.push(...middlewares);
+        } else if (checkRE.test(ctx.req.url!)) {
+          allMiddlewares.push(...middlewares);
+        }
       }
-    }
 
-    return allMiddlewares;
+      const tasks = [...allMiddlewares, flush];
+      return (function next(): Promise<void> {
+        return tasks.shift()!(ctx, next);
+      })();
+    };
   }
 }
diff --git a/src/core/createInstance.ts b/src/core/createInstance.ts
new file mode 100644
index 0000000..839f351
--- /dev/null
+++ b/src/core/createInstance.ts
@@ -0,0 +1,69 @@
+import { combineURL } from '../helpers/combineURL';
+import { buildURL } from '../helpers/buildURL';
+import Axios, {
+  AxiosRequest,
+  AxiosRequestConfig,
+  AxiosRequestHeaders,
+} from './Axios';
+import { mergeConfig } from './mergeConfig';
+
+/**
+ * axios 实例默认配置
+ */
+export interface AxiosInstanceDefaults extends AxiosRequestConfig {
+  /**
+   * 请求头
+   */
+  headers: Required<AxiosRequestHeaders>;
+}
+
+/**
+ * axios 实例
+ */
+export interface AxiosInstance extends AxiosRequest, Axios {
+  /**
+   * 默认请求配置
+   */
+  defaults: AxiosInstanceDefaults;
+  /**
+   * 获取 URI
+   *
+   * @param config 默认配置
+   */
+  getUri(config: AxiosRequestConfig): string;
+  /**
+   * 派生领域
+   *
+   * @param config 默认配置
+   */
+  fork(config: AxiosRequestConfig): AxiosInstance;
+  /**
+   * 扩展实例
+   *
+   * @param config 默认配置
+   */
+  extend(config: AxiosRequestConfig): AxiosInstance;
+}
+
+export function createInstance(config: AxiosRequestConfig, parent?: Axios) {
+  const context = new Axios(config, parent);
+  const instance = context.request as AxiosInstance;
+
+  instance.getUri = function getUri(config: AxiosRequestConfig) {
+    const { url, params, paramsSerializer } = mergeConfig(
+      instance.defaults,
+      config,
+    );
+    return buildURL(url, params, paramsSerializer).replace(/^\?/, '');
+  };
+  instance.extend = function extend(config: AxiosRequestConfig = {}) {
+    config.url = combineURL(instance.defaults.baseURL, config.url);
+    return createInstance(mergeConfig(instance.defaults, config), context);
+  };
+  instance.fork = instance.extend;
+
+  Object.assign(instance, context);
+  Object.setPrototypeOf(instance, Axios.prototype);
+
+  return instance;
+}
diff --git a/src/defaults.ts b/src/defaults.ts
index 804de0a..63aa66c 100644
--- a/src/defaults.ts
+++ b/src/defaults.ts
@@ -1,5 +1,5 @@
 import { getDefaultAdapter } from './adpater/getDefaultAdapter';
-import { AxiosInstanceDefaults } from './axios';
+import { AxiosInstanceDefaults } from './core/createInstance';
 
 const defaults: AxiosInstanceDefaults = {
   // 适配器，在支持的平台中有值。
diff --git a/src/index.ts b/src/index.ts
index e58ab62..3331e82 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -15,10 +15,13 @@ export type {
   AxiosUploadProgressCallback,
 } from './core/Axios';
 export type {
-  MiddlewareContext,
   MiddlewareCallback,
   MiddlewareNext,
 } from './core/MiddlewareManager';
+export type {
+  AxiosInstanceDefaults,
+  AxiosInstance,
+} from './core/createInstance';
 export type {
   AxiosAdapter,
   AxiosAdapterRequestConfig,
@@ -35,11 +38,7 @@ export type {
   AxiosAdapterPlatform,
   AxiosAdapterPlatformTask,
 } from './adpater/createAdapter';
-export type {
-  AxiosInstanceDefaults,
-  AxiosInstance,
-  AxiosStatic,
-} from './axios';
+export type { AxiosStatic } from './axios';
 
 export { CancelToken, isCancel } from './request/cancel';
 export { isAxiosError } from './request/createError';
diff --git a/test/axios.instance.test.ts b/test/axios.instance.test.ts
index 9a1c6c4..0badb6b 100644
--- a/test/axios.instance.test.ts
+++ b/test/axios.instance.test.ts
@@ -1,11 +1,10 @@
-import { describe, test, expect, vi, afterEach } from 'vitest';
+import { describe, test, expect, vi } from 'vitest';
 import { mockAdapter, testEachMethods } from 'scripts/test.utils';
 import {
   PLAIN_METHODS,
   WITH_DATA_METHODS,
   WITH_PARAMS_METHODS,
 } from '@/constants/methods';
-import AxiosDomain from '@/core/AxiosDomain';
 import defaults from '@/defaults';
 import axios from '@/axios';
 
@@ -163,8 +162,4 @@ describe('src/axios.ts', () => {
       'test?id=1',
     );
   });
-
-  test('派生的领域应该为 AxiosDomain 的实例', () => {
-    expect(axios.fork() instanceof AxiosDomain).toBeTruthy();
-  });
 });
diff --git a/test/core/Axios.test.ts b/test/core/Axios.test.ts
index f39bfbd..852870a 100644
--- a/test/core/Axios.test.ts
+++ b/test/core/Axios.test.ts
@@ -10,7 +10,6 @@ import {
   WITH_DATA_METHODS,
   WITH_PARAMS_METHODS,
 } from '@/constants/methods';
-import AxiosDomain from '@/core/AxiosDomain';
 import Axios from '@/core/Axios';
 import axios from '@/axios';
 
@@ -22,10 +21,6 @@ describe('src/core/Axios.ts', () => {
     baseURL: 'http://api.com',
   });
 
-  test('应该继承自 AxiosDomain', () => {
-    expect(new Axios() instanceof AxiosDomain).toBeTruthy();
-  });
-
   test('应该有这些实例属性及方法', () => {
     const c = {
       baseURL: 'http://api.com',
@@ -34,8 +29,6 @@ describe('src/core/Axios.ts', () => {
     expect(axiosObj.defaults).toEqual(c);
     expect(axiosObj.interceptors).toBeTypeOf('object');
     expect(axiosObj.request).toBeTypeOf('function');
-    expect(axiosObj.getUri).toBeTypeOf('function');
-    expect(axiosObj.fork).toBeTypeOf('function');
   });
 
   testEachMethods('%s 应该是一个函数', (k) => {
@@ -354,45 +347,4 @@ describe('src/core/Axios.ts', () => {
     expect(res2).not.toBeCalled();
     expect(rej2).toBeCalled();
   });
-
-  test('应该可以获取 URI', () => {
-    expect(axiosObj.getUri({ url: 'test' })).toBe('test');
-    expect(axiosObj.getUri({ url: 'test', params: { id: 1 } })).toBe(
-      'test?id=1',
-    );
-    expect(
-      axiosObj.getUri({ url: 'test', paramsSerializer: () => 'id=1' }),
-    ).toBe('test?id=1');
-  });
-
-  test('派生的领域应该为 AxiosDomain 的实例', () => {
-    expect(axiosObj.fork() instanceof AxiosDomain).toBeTruthy();
-  });
-
-  test('应该支持 绝对路径/相对路径 派生领域', () => {
-    const a1 = axiosObj.fork({ baseURL: 'test' });
-    const a2 = new Axios().fork({ baseURL: 'test' });
-    const a3 = axiosObj.fork({ baseURL: 'https://api.com' });
-    const a4 = axiosObj.fork();
-
-    expect(a1.defaults.baseURL).toBe('http://api.com/test');
-    expect(a2.defaults.baseURL).toBe('/test');
-    expect(a3.defaults.baseURL).toBe('https://api.com');
-    expect(a4.defaults.baseURL).toBe('http://api.com');
-  });
-
-  test('派生自当前实例的领域应该可以复用当前实例的拦截器', async () => {
-    const axiosObj = new Axios();
-    const req = vi.fn((v) => v);
-    const res = vi.fn((v) => v);
-
-    axiosObj.interceptors.request.use(req);
-    axiosObj.interceptors.response.use(res);
-
-    const a = axiosObj.fork({ baseURL: 'test' });
-    await a.request('test', { adapter: mockAdapter() });
-
-    expect(req).toBeCalled();
-    expect(res).toBeCalled();
-  });
 });
diff --git a/test/core/AxiosDomain.test.ts b/test/core/AxiosDomain.test.ts
deleted file mode 100644
index d37d20d..0000000
--- a/test/core/AxiosDomain.test.ts
+++ /dev/null
@@ -1,240 +0,0 @@
-import { describe, test, expect, vi } from 'vitest';
-import { ignore } from '@/helpers/ignore';
-import {
-  PLAIN_METHODS,
-  WITH_DATA_METHODS,
-  WITH_PARAMS_METHODS,
-} from '@/constants/methods';
-import AxiosDomain from '@/core/AxiosDomain';
-import { AxiosResponse } from '@/core/Axios';
-import { eachMethods } from 'scripts/test.utils';
-
-describe('src/core/AxiosDomain.ts', () => {
-  test('应该有这些实例属性', () => {
-    const c = {
-      baseURL: 'http://api.com',
-    };
-    const a = new AxiosDomain(c, vi.fn());
-
-    expect(a.defaults).toEqual(c);
-    expect(a.request).toBeTypeOf('function');
-
-    eachMethods((k) => {
-      expect(a[k]).toBeTypeOf('function');
-    });
-  });
-
-  test('发送请求时 processRequest 应该被调用', () => {
-    const p = vi.fn();
-    const d = {
-      baseURL: 'http://api.com',
-    };
-    const c = {
-      url: 'test',
-      params: {
-        id: 1,
-      },
-      data: {
-        id: 1,
-      },
-    };
-
-    new AxiosDomain(d, p).request(c);
-
-    expect(p).toBeCalled();
-    expect(p.mock.calls[0][0]).toEqual({
-      ...d,
-      ...c,
-    });
-  });
-
-  test('请求方法应该支持空参数', () => {
-    const cb = vi.fn();
-    const a = new AxiosDomain({}, cb);
-
-    a.request('test');
-
-    PLAIN_METHODS.forEach((k) => a[k]('test'));
-    WITH_PARAMS_METHODS.forEach((k) => a[k]('test'));
-    WITH_DATA_METHODS.forEach((k) => a[k]('test'));
-
-    const l =
-      PLAIN_METHODS.length +
-      WITH_PARAMS_METHODS.length +
-      WITH_DATA_METHODS.length +
-      1;
-    expect(cb.mock.calls.length).toBe(l);
-    cb.mock.calls.forEach(([config]) => expect(config.url).toBe('test'));
-  });
-
-  test('应该可以调用请求方法', () => {
-    const cb = vi.fn();
-    const d = {
-      baseURL: 'http://api.com',
-    };
-    const u = 'test';
-    const c = {
-      params: {
-        id: 1,
-      },
-      data: {
-        id: 1,
-      },
-    };
-    const a = new AxiosDomain(d, async (config) => {
-      cb();
-
-      expect(config.baseURL).toBe(d.baseURL);
-      expect(config.url).toBe(u);
-      expect(config.params).toEqual(c.params);
-      expect(config.data).toEqual(c.data);
-
-      return {} as AxiosResponse;
-    });
-
-    a.request(u, c);
-
-    PLAIN_METHODS.forEach((k) => a[k](u, c));
-    WITH_PARAMS_METHODS.forEach((k) => a[k](u, c.params, ignore(c, 'params')));
-    WITH_DATA_METHODS.forEach((k) => a[k](u, c.data, ignore(c, 'data')));
-
-    const l =
-      PLAIN_METHODS.length +
-      WITH_PARAMS_METHODS.length +
-      WITH_DATA_METHODS.length +
-      1;
-    expect(cb.mock.calls.length).toBe(l);
-  });
-
-  test('应该可以直接传递 config 调用请求方法', () => {
-    const cb = vi.fn();
-    const d = {
-      baseURL: 'http://api.com',
-    };
-    const c = {
-      url: 'test',
-      params: {
-        id: 1,
-      },
-      data: {
-        id: 1,
-      },
-    };
-    const a = new AxiosDomain(d, async (config) => {
-      cb();
-
-      expect(config.baseURL).toBe(d.baseURL);
-      expect(config.url).toBe(c.url);
-      expect(config.params).toEqual(c.params);
-      expect(config.data).toEqual(c.data);
-
-      return {} as AxiosResponse;
-    });
-
-    a.request(c);
-
-    PLAIN_METHODS.forEach((k) => a[k](c.url, ignore(c, 'url')));
-    WITH_PARAMS_METHODS.forEach((k) =>
-      a[k](c.url, c.params, ignore(c, 'url', 'params')),
-    );
-    WITH_DATA_METHODS.forEach((k) =>
-      a[k](c.url, c.data, ignore(c, 'url', 'data')),
-    );
-
-    const l =
-      PLAIN_METHODS.length +
-      WITH_PARAMS_METHODS.length +
-      WITH_DATA_METHODS.length +
-      1;
-    expect(cb.mock.calls.length).toBe(l);
-  });
-
-  test('应该支持深度合并 params', () => {
-    const d = {
-      baseURL: 'http://api.com',
-    };
-    const p = {
-      v1: 1,
-      v2: {
-        v1: 1,
-      },
-    };
-    const c = {
-      params: {
-        v2: {
-          v2: 2,
-        },
-        v3: 3,
-      },
-    };
-
-    const a = new AxiosDomain(d, async (config) => {
-      expect(config.params).toEqual({
-        v1: 1,
-        v2: {
-          v1: 1,
-          v2: 2,
-        },
-        v3: 3,
-      });
-
-      return {} as AxiosResponse;
-    });
-
-    WITH_PARAMS_METHODS.forEach((k) => a[k]('test', p, c));
-  });
-
-  test('应该只取传入的 data', () => {
-    const ds = {
-      baseURL: 'http://api.com',
-    };
-    const d = {
-      v: 1,
-    };
-    const c = {
-      v: 2,
-    };
-
-    const a = new AxiosDomain(ds, async (config) => {
-      expect(config.data).toEqual({
-        v: 1,
-      });
-
-      return {} as AxiosResponse;
-    });
-
-    WITH_DATA_METHODS.forEach((k) => a[k]('test', d, c));
-  });
-
-  test('应该支持多种类型 data', () => {
-    const ds = {
-      baseURL: 'http://api.com',
-    };
-
-    const str = '11';
-    const obj = {};
-    const buff = new ArrayBuffer(0);
-
-    const testStr = new AxiosDomain(ds, async (config) => {
-      expect(config.data).toBe(str);
-
-      return {} as AxiosResponse;
-    });
-    const testObj = new AxiosDomain(ds, async (config) => {
-      expect(config.data).toBe(obj);
-
-      return {} as AxiosResponse;
-    });
-    const testBuff = new AxiosDomain(ds, async (config) => {
-      expect(config.data).toBe(buff);
-
-      return {} as AxiosResponse;
-    });
-
-    WITH_DATA_METHODS.forEach((k) => {
-      testStr[k]('test', str);
-      testObj[k]('test', obj);
-      testBuff[k]('test', buff);
-    });
-  });
-});
diff --git a/test/core/MiddlewareManager.test.ts b/test/core/MiddlewareManager.test.ts
index 3d80831..f615531 100644
--- a/test/core/MiddlewareManager.test.ts
+++ b/test/core/MiddlewareManager.test.ts
@@ -3,14 +3,18 @@ import MiddlewareManager from '@/core/MiddlewareManager';
 
 describe('src/core/MiddlewareManager.ts', () => {
   test('应该有这些实例属性', () => {
-    const m = new MiddlewareManager();
+    const m = new MiddlewareManager(vi.fn());
 
     expect(m.use).toBeTypeOf('function');
     expect(m.wrap).toBeTypeOf('function');
   });
 
   test('应该可以添加中间件回调', async () => {
-    const m = new MiddlewareManager();
+    const flush = vi.fn(async (ctx) => {
+      expect(ctx.req.url).toBe('test');
+      ctx.res = res;
+    });
+    const m = new MiddlewareManager(flush);
     const ctx = {
       req: { url: 'https://api.com' },
       res: null,
@@ -24,20 +28,20 @@ describe('src/core/MiddlewareManager.ts', () => {
       await next();
       expect(ctx.res).toBe(res);
     });
-    const flush = vi.fn(async (ctx) => {
-      expect(ctx.req.url).toBe('test');
-      ctx.res = res;
-    });
 
     m.use(midde);
-    await m.wrap(flush)(ctx);
+    await m.flush(ctx);
 
     expect(ctx.res).toBe(res);
     expect(midde).toBeCalled();
   });
 
   test('应该可以给路径添加中间件回调', async () => {
-    const m = new MiddlewareManager();
+    const flush = vi.fn(async (ctx) => {
+      ctx.res = res;
+    });
+
+    const m = new MiddlewareManager(flush);
     const ctx1 = {
       req: {
         baseURL: 'https://api.com',
@@ -60,18 +64,15 @@ describe('src/core/MiddlewareManager.ts', () => {
       await next();
       expect(ctx.res).toBe(res);
     });
-    const flush = vi.fn(async (ctx) => {
-      ctx.res = res;
-    });
 
     m.use('/test', midde);
-    await m.wrap(flush)(ctx1);
+    await m.flush(ctx1);
 
     expect(ctx1.res).toBe(res);
     expect(midde).not.toBeCalled();
 
     m.use('/test', midde);
-    await m.wrap(flush)(ctx2);
+    await m.flush(ctx2);
 
     expect(midde).toBeCalled();
   });