diff --git a/babel.config.js b/babel.config.js
index 6bb8a01a..d4c89547 100644
--- a/babel.config.js
+++ b/babel.config.js
@@ -4,8 +4,4 @@ if (process.env.TEST_FRONTEND) {
     config.presets = [ "@babel/preset-env" ];
 }
 
-if (process.env.TEST_BACKEND) {
-    config.plugins = [ "babel-plugin-rewire" ];
-}
-
 module.exports = config;
diff --git a/package-lock.json b/package-lock.json
index da1524c7..a1b01241 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -90,7 +90,6 @@
                 "@vue/compiler-sfc": "~3.3.4",
                 "@vuepic/vue-datepicker": "~3.4.8",
                 "aedes": "^0.46.3",
-                "babel-plugin-rewire": "~1.2.0",
                 "bootstrap": "5.1.3",
                 "chart.js": "~4.2.1",
                 "chartjs-adapter-dayjs-4": "~1.0.4",
@@ -6623,12 +6622,6 @@
                 "@babel/core": "^7.4.0 || ^8.0.0-0 <8.0.0"
             }
         },
-        "node_modules/babel-plugin-rewire": {
-            "version": "1.2.0",
-            "resolved": "https://registry.npmjs.org/babel-plugin-rewire/-/babel-plugin-rewire-1.2.0.tgz",
-            "integrity": "sha512-JBZxczHw3tScS+djy6JPLMjblchGhLI89ep15H3SyjujIzlxo5nr6Yjo7AXotdeVczeBmWs0tF8PgJWDdgzAkQ==",
-            "dev": true
-        },
         "node_modules/babel-preset-current-node-syntax": {
             "version": "1.0.1",
             "resolved": "https://registry.npmjs.org/babel-preset-current-node-syntax/-/babel-preset-current-node-syntax-1.0.1.tgz",
diff --git a/package.json b/package.json
index 9f57e99b..3a9056d6 100644
--- a/package.json
+++ b/package.json
@@ -153,7 +153,6 @@
         "@vue/compiler-sfc": "~3.3.4",
         "@vuepic/vue-datepicker": "~3.4.8",
         "aedes": "^0.46.3",
-        "babel-plugin-rewire": "~1.2.0",
         "bootstrap": "5.1.3",
         "chart.js": "~4.2.1",
         "chartjs-adapter-dayjs-4": "~1.0.4",
diff --git a/server/util-server.js b/server/util-server.js
index 8ab592eb..985fddb6 100644
--- a/server/util-server.js
+++ b/server/util-server.js
@@ -1047,3 +1047,13 @@ module.exports.grpcQuery = async (options) => {
 
     });
 };
+
+// For unit test, export functions
+if (process.env.TEST_BACKEND) {
+    module.exports.__test = {
+        parseCertificateInfo,
+    };
+    module.exports.__getPrivateFunction = (functionName) => {
+        return module.exports.__test[functionName];
+    };
+}
diff --git a/test/backend.spec.js b/test/backend.spec.js
index 0132fb77..bc5ee810 100644
--- a/test/backend.spec.js
+++ b/test/backend.spec.js
@@ -1,5 +1,5 @@
 const { genSecret, DOWN, log} = require("../src/util");
-const utilServerRewire = require("../server/util-server");
+const utilServer = require("../server/util-server");
 const Discord = require("../server/notification-providers/discord");
 const axios = require("axios");
 const { UptimeKumaServer } = require("../server/uptime-kuma-server");
@@ -14,13 +14,13 @@ jest.mock("axios");
 
 describe("Test parseCertificateInfo", () => {
     it("should handle undefined", async () => {
-        const parseCertificateInfo = utilServerRewire.__get__("parseCertificateInfo");
+        const parseCertificateInfo = utilServer.__getPrivateFunction("parseCertificateInfo");
         const info = parseCertificateInfo(undefined);
         expect(info).toEqual(undefined);
     }, 5000);
 
     it("should handle normal cert chain", async () => {
-        const parseCertificateInfo = utilServerRewire.__get__("parseCertificateInfo");
+        const parseCertificateInfo = utilServer.__getPrivateFunction("parseCertificateInfo");
 
         const chain1 = {
             fingerprint: "CF:2C:F3:6A:FE:6B:10:EC:44:77:C8:95:BB:96:2E:06:1F:0E:15:DA",
@@ -52,7 +52,7 @@ describe("Test parseCertificateInfo", () => {
     }, 5000);
 
     it("should handle cert chain with strange circle", async () => {
-        const parseCertificateInfo = utilServerRewire.__get__("parseCertificateInfo");
+        const parseCertificateInfo = utilServer.__getPrivateFunction("parseCertificateInfo");
 
         const chain1 = {
             fingerprint: "CF:2C:F3:6A:FE:6B:10:EC:44:77:C8:95:BB:96:2E:06:1F:0E:15:DA",
@@ -92,7 +92,7 @@ describe("Test parseCertificateInfo", () => {
     }, 5000);
 
     it("should handle cert chain with last undefined (should be happen in real, but just in case)", async () => {
-        const parseCertificateInfo = utilServerRewire.__get__("parseCertificateInfo");
+        const parseCertificateInfo = utilServer.__getPrivateFunction("parseCertificateInfo");
 
         const chain1 = {
             fingerprint: "CF:2C:F3:6A:FE:6B:10:EC:44:77:C8:95:BB:96:2E:06:1F:0E:15:DA",
@@ -213,22 +213,22 @@ describe("Test Discord Notification Provider", () => {
 
 describe("The function filterAndJoin", () => {
     it("should join and array of strings to one string", () => {
-        const result = utilServerRewire.filterAndJoin([ "one", "two", "three" ]);
+        const result = utilServer.filterAndJoin([ "one", "two", "three" ]);
         expect(result).toBe("onetwothree");
     });
 
     it("should join strings using a given connector", () => {
-        const result = utilServerRewire.filterAndJoin([ "one", "two", "three" ], "-");
+        const result = utilServer.filterAndJoin([ "one", "two", "three" ], "-");
         expect(result).toBe("one-two-three");
     });
 
     it("should filter null, undefined and empty strings before joining", () => {
-        const result = utilServerRewire.filterAndJoin([ undefined, "", "three" ], "--");
+        const result = utilServer.filterAndJoin([ undefined, "", "three" ], "--");
         expect(result).toBe("three");
     });
 
     it("should return an empty string if all parts are filtered out", () => {
-        const result = utilServerRewire.filterAndJoin([ undefined, "", "" ], "--");
+        const result = utilServer.filterAndJoin([ undefined, "", "" ], "--");
         expect(result).toBe("");
     });
 });