diff --git a/README.md b/README.md
index ff354fc..6a5c26b 100644
--- a/README.md
+++ b/README.md
@@ -330,7 +330,7 @@ Write functions `lib.js`
 
 ```js
 // Make random color e.g. #34FFFF
-function randColor() {
+exports.makeColor = function () {
   const letters = '0123456789ABCDEF';
   let color = '#';
   for (let i = 0; i < 6; i++) {
@@ -340,7 +340,7 @@ function randColor() {
 }
 
 // Detect date in ISO8601(e.g. 2021-06-02:00:00.000Z) format
-function isDate(date) {
+exports.isDate = function (date) {
   return /^\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}\.\d{3}Z$/.test(date)
 }
 ```
@@ -354,7 +354,7 @@ Use functions
    test1: {
      req: {
        body: {
-        // call the `randColor` function to generate random colors
+        // call the `makeColor` function to generate random colors
         color:'makeColor()', @eval 
        }
      },
diff --git a/README.zh-CN.md b/README.zh-CN.md
index 096b969..6305bc9 100644
--- a/README.zh-CN.md
+++ b/README.zh-CN.md
@@ -327,9 +327,9 @@ Apitest 使用JSONA格式描述测试用例。 JSON描述数据，注解描述
 ```js
 
 // 创建随机颜色
-function randColor() {
-  const letters = '0123456789ABCDEF';
-  let color = '#';
+exports.makeColor = function () {
+  const letters = "0123456789ABCDEF";
+  let color = "#";
   for (let i = 0; i < 6; i++) {
     color += letters[Math.floor(Math.random() * 16)];
   }
@@ -337,7 +337,7 @@ function randColor() {
 }
 
 // 判断是否是ISO8601(2021-06-02:00:00.000Z)风格的时间字符串
-function isDate(date) {
+exports.isDate = function (date) {
   return /^\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}\.\d{3}Z$/.test(date)
 }
 ```
@@ -350,7 +350,7 @@ function isDate(date) {
   test1: {
     req: {
       body: {
-        color: 'makeColor()', @eval // 调用 `randColor` 函数生成随机颜色
+        color: 'makeColor()', @eval // 调用 `makeColor` 函数生成随机颜色
       }
     },
     res: {
diff --git a/src/Loader.ts b/src/Loader.ts
index 180ecd4..bfa61e3 100644
--- a/src/Loader.ts
+++ b/src/Loader.ts
@@ -13,10 +13,13 @@ export interface Module {
   describe: string;
 }
 
+export interface JSLib {
+}
+
 export default class Loader {
   private workDir: string;
   private cases: Cases;
-  private jslibs: string[] = [];
+  private jslib: JSLib = {};
   private clients: Clients = new Clients();
   private modules: Module[] = [];
   private mixin: JsonaObject;
@@ -58,7 +61,7 @@ export default class Loader {
       mainFile,
       cases: this.cases,
       clients: this.clients,
-      jslibs: this.jslibs,
+      jslibs: this.jslib,
     };
   }
 
@@ -128,18 +131,11 @@ export default class Loader {
       const  libFile = path.resolve(this.workDir, libFileName);
       let jslib;
       try {
-        jslib = await fs.readFile(libFile, "utf8");
-      } catch (err) {
-        throw new Error(`main@jslib(${libName}): load ${libFileName} failed`);
-      }
-      try {
-        const context = {};
-        const script = new vm.Script(jslib);
-        script.runInNewContext(context);
+        jslib = require(libFile);
       } catch (err) {
         throw new Error(`main@jslib(${libName}): load ${libFileName} throw ${err.message}${toPosString(anno.position)}`);
       }
-      this.jslibs.push(jslib);
+      _.merge(this.jslib, jslib);
     } else {
       throw new Error(`[main@jslib] should have string value${toPosString(anno.position)}`);
     }
diff --git a/src/Session.ts b/src/Session.ts
index c98fa65..4854886 100644
--- a/src/Session.ts
+++ b/src/Session.ts
@@ -4,6 +4,7 @@ import * as fs from "fs/promises";
 import * as crypto from "crypto";
 import * as _ from "lodash";
 import { Case, Unit } from "./Cases";
+import { JSLib } from "./Loader";
 
 export const EMPTY_CACHE = { cursor: "", tests: {} };
 
@@ -11,16 +12,16 @@ export default class Session {
   private cacheFile: string;
   private cache: Cache;
   private unitIds: string[];
-  private jslibs: string[] = [];
+  private jslib: JSLib;
 
-  public constructor(cacheFile: string, unitIds: string[], cache: Cache, jslibs: string[]) {
+  public constructor(cacheFile: string, unitIds: string[], cache: Cache, jslib: JSLib) {
     this.cacheFile = cacheFile;
     this.unitIds = unitIds;
     this.cache = cache;
-    this.jslibs = jslibs;
+    this.jslib = jslib;
   }
 
-  public static async create(mainFile: string, unitIds: string[], jslibs: string[]) {
+  public static async create(mainFile: string, unitIds: string[], jslibs: any) {
     const cacheFileName = "apitest" + md5(mainFile) + ".json";
     const cacheFile = path.resolve(os.tmpdir(), cacheFileName);
     const cache = await loadCache(cacheFile);
@@ -59,7 +60,7 @@ export default class Session {
       _.set(state, ["req"], req);
       _.set(this.cache.tests, testcase.paths.concat(["req"]), req);
     }
-    return { state, jslibs: this.jslibs };
+    return { state, jslib: this.jslib };
   }
 
   public async saveValue(testcase: Case, key: string, value: any, persist = true) {
@@ -89,7 +90,7 @@ export default class Session {
 }
 
 export interface VmContext {
-  jslibs: string[],
+  jslib: JSLib,
   state: any;
 }
 
diff --git a/src/utils.ts b/src/utils.ts
index 625e452..30f22a3 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -89,12 +89,13 @@ export function evalValue(paths: string[], ctx: VmContext, code: string, anno =
   if (!expressions[lastIdx].trim().startsWith("return")) {
     expressions[lastIdx] = "return " + expressions[lastIdx];
   }
-  const patchedCode = ctx.jslibs.join("\n") + expressions.join(";");
+  const patchedCode = expressions.join(";");
   const EXPORT_KEY = "__exports__";
   ctx.state[EXPORT_KEY] = null;
   try {
     const wrapCode = `${EXPORT_KEY} = (function(){${patchedCode};}())`;
     const script = new vm.Script(wrapCode);
+    _.merge(ctx.state, ctx.jslib);
     script.runInNewContext(ctx.state);
     return ctx.state[EXPORT_KEY];
   } catch (err) {
diff --git a/tests/__snapshots__/loader.test.js.snap b/tests/__snapshots__/loader.test.js.snap
index a45a5bf..0629abe 100644
--- a/tests/__snapshots__/loader.test.js.snap
+++ b/tests/__snapshots__/loader.test.js.snap
@@ -11,11 +11,6 @@ exports[`loader invalid jslib 1`] = `
 `;
 
 exports[`loader invalid jslib js 1`] = `
-"main@jslib(invalid-jslib-404): load invalid-jslib-404.js failed
-"
-`;
-
-exports[`loader invalid jslib js2 1`] = `
 "main@jslib(invalid-jslib): load invalid-jslib.js throw Unexpected end of input at line 2 col 4
 "
 `;
diff --git a/tests/fixtures/loader/invalid-jslib-js.jsona b/tests/fixtures/loader/invalid-jslib-js.jsona
index 2e8e689..4e38af9 100644
--- a/tests/fixtures/loader/invalid-jslib-js.jsona
+++ b/tests/fixtures/loader/invalid-jslib-js.jsona
@@ -1,3 +1,3 @@
 {
-  @jslib("invalid-jslib-404")
+  @jslib("invalid-jslib")
 }
\ No newline at end of file
diff --git a/tests/fixtures/loader/invalid-jslib-js2.jsona b/tests/fixtures/loader/invalid-jslib-js2.jsona
deleted file mode 100644
index 4e38af9..0000000
--- a/tests/fixtures/loader/invalid-jslib-js2.jsona
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  @jslib("invalid-jslib")
-}
\ No newline at end of file
diff --git a/tests/fixtures/loader/jslib.js b/tests/fixtures/loader/jslib.js
new file mode 100644
index 0000000..3c8d0dd
--- /dev/null
+++ b/tests/fixtures/loader/jslib.js
@@ -0,0 +1,12 @@
+exports.makeColor = function () {
+  const letters = "0123456789ABCDEF";
+  let color = "#";
+  for (let i = 0; i < 6; i++) {
+    color += letters[Math.floor(Math.random() * 16)];
+  }
+  return color;
+};
+
+exports.isDate = function (date) {
+  return /^\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}\.\d{3}Z$/.test(date);
+};
diff --git a/tests/fixtures/loader/jslib.jsona b/tests/fixtures/loader/jslib.jsona
new file mode 100644
index 0000000..9044eba
--- /dev/null
+++ b/tests/fixtures/loader/jslib.jsona
@@ -0,0 +1,11 @@
+{
+  @jslib("jslib")
+  test1: { @client("echo")
+    req: {
+      color: 'makeColor()', @eval 
+    },
+    res: {
+      color: `/#[0-9A-F]{6}/.test($)`, @eval
+    }
+  }
+}
\ No newline at end of file
diff --git a/tests/loader.test.js b/tests/loader.test.js
index 4e8a310..8c1756e 100644
--- a/tests/loader.test.js
+++ b/tests/loader.test.js
@@ -11,11 +11,6 @@ describe("loader", () => {
     expect(code).toEqual(1);
     expect(stdout).toMatchSnapshot();
   });
-  test("invalid jslib js2", async () => {
-    const { stdout, code } = await spwanTest("loader/invalid-jslib-js2.jsona", ["--ci"]);
-    expect(code).toEqual(1);
-    expect(stdout).toMatchSnapshot();
-  });
   test("invalid jslib", async () => {
     const { stdout, code } = await spwanTest("loader/invalid-jslib.jsona", ["--ci"]);
     expect(code).toEqual(1);
@@ -66,7 +61,10 @@ describe("loader", () => {
     expect(code).toEqual(1);
     expect(stdout).toMatchSnapshot();
   });
-
+  test("jslib", async () => {
+    const { code } = await spwanTest("loader/jslib.jsona", ["--ci"]);
+    expect(code).toEqual(0);
+  });
   test("target file not found", async () => {
     const { stdout, code } = await spwanTest("loader/notfound.jsona", ["--ci"]);
     expect(code).toEqual(1);