diff --git a/.eslintrc.js b/.eslintrc.js
index 9a63b414b..2d2d84042 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -119,5 +119,12 @@ module.exports = {
                 eqeqeq: "off",
             },
         },
+        // Backend: no `any`
+        {
+            files: ["server/**/*.ts"],
+            rules: {
+                "@typescript-eslint/no-explicit-any": "error",
+            },
+        },
     ],
 };
diff --git a/extra/precompile-server.js b/extra/precompile-server.js
index 31bc5b914..72c7e685c 100644
--- a/extra/precompile-server.js
+++ b/extra/precompile-server.js
@@ -7,7 +7,7 @@ const path = require("path");
 const esbuild = require("esbuild");
 
 const root = path.resolve(__dirname, "..");
-const esmEntries = ["server/server.js", "server/util-server.js"];
+const esmEntries = ["server/server.js"];
 
 /**
  * Collect every .ts file below a directory.
diff --git a/extra/run-backend-tests.mjs b/extra/run-backend-tests.mjs
index 6c607b254..6f533ebb3 100644
--- a/extra/run-backend-tests.mjs
+++ b/extra/run-backend-tests.mjs
@@ -8,7 +8,7 @@ const PATTERNS = [
     "test/frontend-test/**/*.js",
 ];
 const CONTAINER_MARKER = "testcontainers";
-const NODE_ARGS = ["--import=tsx", "--test"];
+const NODE_ARGS = ["--import=tsx", "--import=./test/setup.ts", "--test"];
 const extraArgs = process.argv.slice(2);
 
 const files = PATTERNS.flatMap((pattern) => globSync(pattern, { exclude: ["**/node_modules/**"] })).sort();
diff --git a/server/auth.ts b/server/auth.ts
index b413523bb..608675d02 100644
--- a/server/auth.ts
+++ b/server/auth.ts
@@ -1,6 +1,7 @@
 import expressBasicAuth from "express-basic-auth";
 import dayjs from "dayjs";
 import { R } from "redbean-node";
+import type { Bean } from "redbean-node";
 import type express from "express";
 import { log } from "../src/util";
 import { loginRateLimiter, apiRateLimiter } from "./rate-limiter";
@@ -28,7 +29,7 @@ export async function login(username: string, password: string) {
         return null;
     }
 
-    const user: any = await R.findOne("user", "TRIM(username) = ? AND active = 1 ", [username.trim()]);
+    const user: Bean | null = await R.findOne("user", "TRIM(username) = ? AND active = 1 ", [username.trim()]);
 
     if (user && passwordHash.verify(password, user.password)) {
         // Upgrade the hash to bcrypt
@@ -77,7 +78,7 @@ async function verifyLegacyAPIKey(key: string) {
         return false;
     }
 
-    const hash: any = await R.findOne("api_key", " id=? ", [index]);
+    const hash: Bean | null = await R.findOne("api_key", " id=? ", [index]);
 
     if (hash === null) {
         return false;
diff --git a/server/better-auth.ts b/server/better-auth.ts
index d8c960eeb..68461ded2 100644
--- a/server/better-auth.ts
+++ b/server/better-auth.ts
@@ -441,7 +441,7 @@ export async function checkPassword(username: string, password: string): Promise
     const { adapter, password: passwordVerifier } = await auth().$context;
     const internalAdapter = await authInternal();
 
-    const user = await adapter.findOne<Record<string, any>>({
+    const user = await adapter.findOne<Record<string, unknown>>({
         model: "user",
         where: [{ field: "username", value: username }],
     });
diff --git a/server/check-version.js b/server/check-version.js
index 79dfa10af..741eb076a 100644
--- a/server/check-version.js
+++ b/server/check-version.js
@@ -1,4 +1,4 @@
-const { setSetting, setting } = require("./util-server");
+const { setSetting, setting } = require("./util");
 const axios = require("axios");
 const compareVersions = require("compare-versions");
 const { log } = require("../src/util");
diff --git a/server/docker.js b/server/docker.js
index bd7c5e116..8107ca6fc 100644
--- a/server/docker.js
+++ b/server/docker.js
@@ -4,7 +4,7 @@ const https = require("https");
 const fsAsync = require("fs").promises;
 const path = require("path");
 const Database = require("./database");
-const { axiosAbortSignal, fsExists } = require("./util-server");
+const { axiosAbortSignal, fsExists } = require("./util");
 
 class DockerHost {
     static CertificateFileNameCA = "ca.pem";
diff --git a/server/heartbeat-emit.ts b/server/heartbeat-emit.ts
index 97d2b7839..fee691b5d 100644
--- a/server/heartbeat-emit.ts
+++ b/server/heartbeat-emit.ts
@@ -1,4 +1,4 @@
-import { getTotalClientInRoom } from "./util-server";
+import { getTotalClientInRoom } from "./util";
 
 /**
  * Room every logged-in socket joins; v3 has a single dashboard.
diff --git a/server/model/domain_expiry.js b/server/model/domain_expiry.js
index 6e4fcf56c..a160a2214 100644
--- a/server/model/domain_expiry.js
+++ b/server/model/domain_expiry.js
@@ -2,7 +2,7 @@ const { BeanModel } = require("redbean-node/dist/bean-model");
 const { R } = require("redbean-node");
 const { log, TYPES_WITH_DOMAIN_EXPIRY_SUPPORT_VIA_FIELD } = require("../../src/util");
 const { parse: parseTld } = require("tldts");
-const { setting, setSetting } = require("../util-server");
+const { setting, setSetting } = require("../util");
 const { Notification } = require("../notification");
 const TranslatableError = require("../translatable-error");
 const dayjs = require("dayjs");
diff --git a/server/model/monitor.js b/server/model/monitor.js
index 09b86c1ae..ea0c75ebf 100644
--- a/server/model/monitor.js
+++ b/server/model/monitor.js
@@ -38,7 +38,7 @@ const {
     axiosAbortSignal,
     encodeBase64,
     checkCertExpiryNotifications,
-} = require("../util-server");
+} = require("../util");
 const { R } = require("redbean-node");
 const { BeanModel } = require("redbean-node/dist/bean-model");
 const { Notification } = require("../notification");
diff --git a/server/model/status_page.js b/server/model/status_page.js
index 66728d39e..6d3a400a1 100644
--- a/server/model/status_page.js
+++ b/server/model/status_page.js
@@ -9,7 +9,7 @@ const { Feed } = require("feed");
 const config = require("../config");
 const dayjs = require("dayjs");
 
-const { setting } = require("../util-server");
+const { setting } = require("../util");
 const {
     STATUS_PAGE_ALL_DOWN,
     STATUS_PAGE_ALL_UP,
diff --git a/server/modules/dayjs/plugin/timezone.d.ts b/server/modules/dayjs/plugin/timezone.d.ts
deleted file mode 100644
index 4d98fc7f4..000000000
--- a/server/modules/dayjs/plugin/timezone.d.ts
+++ /dev/null
@@ -1,20 +0,0 @@
-import { PluginFunc, ConfigType } from "dayjs";
-
-declare const plugin: PluginFunc;
-export = plugin;
-
-declare module "dayjs" {
-    interface Dayjs {
-        tz(timezone?: string, keepLocalTime?: boolean): Dayjs;
-        offsetName(type?: "short" | "long"): string | undefined;
-    }
-
-    interface DayjsTimezone {
-        (date: ConfigType, timezone?: string): Dayjs;
-        (date: ConfigType, format: string, timezone?: string): Dayjs;
-        guess(): string;
-        setDefault(timezone?: string): void;
-    }
-
-    const tz: DayjsTimezone;
-}
diff --git a/server/modules/dayjs/plugin/timezone.js b/server/modules/dayjs/plugin/timezone.js
deleted file mode 100644
index b973ece52..000000000
--- a/server/modules/dayjs/plugin/timezone.js
+++ /dev/null
@@ -1,130 +0,0 @@
-/**
- * Copy from node_modules/dayjs/plugin/timezone.js
- * Try to fix https://github.com/louislam/uptime-kuma/issues/2318
- * Source: https://github.com/iamkun/dayjs/tree/dev/src/plugin/utc
- * License: MIT
- */
-!(function (t, e) {
-    // eslint-disable-next-line no-undef
-    typeof exports == "object" && typeof module != "undefined"
-        ? (module.exports = e())
-        : typeof define == "function" && define.amd
-          ? define(e)
-          : ((t = typeof globalThis != "undefined" ? globalThis : t || self).dayjs_plugin_timezone = e());
-})(this, function () {
-    "use strict";
-    let t = {
-        year: 0,
-        month: 1,
-        day: 2,
-        hour: 3,
-        minute: 4,
-        second: 5,
-    };
-    let e = {};
-    return function (n, i, o) {
-        let r;
-        let a = function (t, n, i) {
-            void 0 === i && (i = {});
-            let o = new Date(t);
-            let r = (function (t, n) {
-                void 0 === n && (n = {});
-                let i = n.timeZoneName || "short";
-                let o = t + "|" + i;
-                let r = e[o];
-                return (
-                    r ||
-                        ((r = new Intl.DateTimeFormat("en-US", {
-                            hour12: !1,
-                            timeZone: t,
-                            year: "numeric",
-                            month: "2-digit",
-                            day: "2-digit",
-                            hour: "2-digit",
-                            minute: "2-digit",
-                            second: "2-digit",
-                            timeZoneName: i,
-                        })),
-                        (e[o] = r)),
-                    r
-                );
-            })(n, i);
-            return r.formatToParts(o);
-        };
-        let u = function (e, n) {
-            let i = a(e, n);
-            let r = [];
-            let u = 0;
-            for (; u < i.length; u += 1) {
-                let f = i[u];
-                let s = f.type;
-                let m = f.value;
-                let c = t[s];
-                c >= 0 && (r[c] = parseInt(m, 10));
-            }
-            let d = r[3];
-            let l = d === 24 ? 0 : d;
-            let v = r[0] + "-" + r[1] + "-" + r[2] + " " + l + ":" + r[4] + ":" + r[5] + ":000";
-            let h = +e;
-            return (o.utc(v).valueOf() - (h -= h % 1e3)) / 6e4;
-        };
-        let f = i.prototype;
-        ((f.tz = function (t, e) {
-            void 0 === t && (t = r);
-            let n = this.utcOffset();
-            let i = this.toDate();
-            let a = i.toLocaleString("en-US", { timeZone: t }).replace("\u202f", " ");
-            let u = Math.round((i - new Date(a)) / 1e3 / 60);
-            let f = o(a)
-                .$set("millisecond", this.$ms)
-                .utcOffset(15 * -Math.round(i.getTimezoneOffset() / 15) - u, !0);
-            if (e) {
-                let s = f.utcOffset();
-                f = f.add(n - s, "minute");
-            }
-            return ((f.$x.$timezone = t), f);
-        }),
-            (f.offsetName = function (t) {
-                let e = this.$x.$timezone || o.tz.guess();
-                let n = a(this.valueOf(), e, { timeZoneName: t }).find(function (t) {
-                    return t.type.toLowerCase() === "timezonename";
-                });
-                return n && n.value;
-            }));
-        let s = f.startOf;
-        ((f.startOf = function (t, e) {
-            if (!this.$x || !this.$x.$timezone) {
-                return s.call(this, t, e);
-            }
-            let n = o(this.format("YYYY-MM-DD HH:mm:ss:SSS"));
-            return s.call(n, t, e).tz(this.$x.$timezone, !0);
-        }),
-            (o.tz = function (t, e, n) {
-                let i = n && e;
-                let a = n || e || r;
-                let f = u(+o(), a);
-                if (typeof t != "string") {
-                    return o(t).tz(a);
-                }
-                let s = (function (t, e, n) {
-                    let i = t - 60 * e * 1e3;
-                    let o = u(i, n);
-                    if (e === o) {
-                        return [i, e];
-                    }
-                    let r = u((i -= 60 * (o - e) * 1e3), n);
-                    return o === r ? [i, o] : [t - 60 * Math.min(o, r) * 1e3, Math.max(o, r)];
-                })(o.utc(t, i).valueOf(), f, a);
-                let m = s[0];
-                let c = s[1];
-                let d = o(m).utcOffset(c);
-                return ((d.$x.$timezone = a), d);
-            }),
-            (o.tz.guess = function () {
-                return Intl.DateTimeFormat().resolvedOptions().timeZone;
-            }),
-            (o.tz.setDefault = function (t) {
-                r = t;
-            }));
-    };
-});
diff --git a/server/monitor-tls.ts b/server/monitor-tls.ts
index e1228aa2a..dabddb469 100644
--- a/server/monitor-tls.ts
+++ b/server/monitor-tls.ts
@@ -1,4 +1,4 @@
-import { checkCertificate, checkCertificateHostname } from "./util-server";
+import { checkCertificate, checkCertificateHostname } from "./util";
 
 /** Minimal TLS socket shape needed for the certificate info */
 export interface TlsSocketLike {
diff --git a/server/monitor-types/globalping.js b/server/monitor-types/globalping.js
index 5b235d7d9..0c463654e 100644
--- a/server/monitor-types/globalping.js
+++ b/server/monitor-types/globalping.js
@@ -8,7 +8,7 @@ const {
     encodeBase64,
     getDaysRemaining,
     checkCertExpiryNotifications,
-} = require("../util-server");
+} = require("../util");
 const { R } = require("redbean-node");
 
 /**
diff --git a/server/monitor-types/rabbitmq.js b/server/monitor-types/rabbitmq.js
index bd07e9918..2d35ab25d 100644
--- a/server/monitor-types/rabbitmq.js
+++ b/server/monitor-types/rabbitmq.js
@@ -1,6 +1,6 @@
 const { MonitorType } = require("./monitor-type");
 const { log, UP } = require("../../src/util");
-const { axiosAbortSignal } = require("../util-server");
+const { axiosAbortSignal } = require("../util");
 const axios = require("axios");
 
 class RabbitMqMonitorType extends MonitorType {
diff --git a/server/monitor-types/real-browser-monitor-type.js b/server/monitor-types/real-browser-monitor-type.js
index e2d4ef9fe..da2ad043b 100644
--- a/server/monitor-types/real-browser-monitor-type.js
+++ b/server/monitor-types/real-browser-monitor-type.js
@@ -7,7 +7,7 @@ const path = require("path");
 const Database = require("../database");
 const config = require("../config");
 const { RemoteBrowser } = require("../remote-browser");
-const { commandExists } = require("../util-server");
+const { commandExists } = require("../util");
 
 /**
  * Cached instance of a browser
diff --git a/server/monitor-types/steam.js b/server/monitor-types/steam.js
index 5eaad8c1c..86342f315 100644
--- a/server/monitor-types/steam.js
+++ b/server/monitor-types/steam.js
@@ -6,7 +6,7 @@ const {
     PING_PER_REQUEST_TIMEOUT_DEFAULT,
 } = require("../../src/util");
 const { Settings } = require("../settings");
-const { checkStatusCode } = require("../util-server");
+const { checkStatusCode } = require("../util");
 const { ping } = require("./ping");
 const axios = require("axios");
 const crypto = require("crypto");
diff --git a/server/monitor-types/websocket-upgrade.js b/server/monitor-types/websocket-upgrade.js
index 97ef77b60..d91d48d0f 100644
--- a/server/monitor-types/websocket-upgrade.js
+++ b/server/monitor-types/websocket-upgrade.js
@@ -1,7 +1,7 @@
 const { MonitorType } = require("./monitor-type");
 const WebSocket = require("ws");
 const { UP } = require("../../src/util");
-const { checkStatusCode, getOidcTokenClientCredentials } = require("../util-server");
+const { checkStatusCode, getOidcTokenClientCredentials } = require("../util");
 // Define closing error codes https://www.iana.org/assignments/websocket/websocket.xml#close-code-number
 const WS_ERR_CODE = {
     1002: "Protocol error",
diff --git a/server/notification-providers/Webpush.js b/server/notification-providers/Webpush.js
index 86b94c325..c4564d9b2 100644
--- a/server/notification-providers/Webpush.js
+++ b/server/notification-providers/Webpush.js
@@ -1,6 +1,6 @@
 const NotificationProvider = require("./notification-provider");
 const webpush = require("web-push");
-const { setting } = require("../util-server");
+const { setting } = require("../util");
 
 class Webpush extends NotificationProvider {
     name = "Webpush";
diff --git a/server/notification-providers/heii-oncall.js b/server/notification-providers/heii-oncall.js
index 1e66f0d72..b925fa8d9 100644
--- a/server/notification-providers/heii-oncall.js
+++ b/server/notification-providers/heii-oncall.js
@@ -1,5 +1,5 @@
 const { UP, DOWN, getMonitorRelativeURL } = require("../../src/util");
-const { setting } = require("../util-server");
+const { setting } = require("../util");
 
 const NotificationProvider = require("./notification-provider");
 const axios = require("axios");
diff --git a/server/notification-providers/notifery.js b/server/notification-providers/notifery.js
index 99cc7bed2..9c3b030ed 100644
--- a/server/notification-providers/notifery.js
+++ b/server/notification-providers/notifery.js
@@ -1,5 +1,5 @@
 const { getMonitorRelativeURL, UP } = require("../../src/util");
-const { setting } = require("../util-server");
+const { setting } = require("../util");
 const NotificationProvider = require("./notification-provider");
 const axios = require("axios");
 
diff --git a/server/notification-providers/pushover.js b/server/notification-providers/pushover.js
index 6d935a3a3..79cbcf384 100644
--- a/server/notification-providers/pushover.js
+++ b/server/notification-providers/pushover.js
@@ -1,5 +1,5 @@
 const { getMonitorRelativeURL } = require("../../src/util");
-const { setting } = require("../util-server");
+const { setting } = require("../util");
 const { UP } = require("../../src/util");
 
 const NotificationProvider = require("./notification-provider");
diff --git a/server/notification-providers/slack.js b/server/notification-providers/slack.js
index 32f06641c..25e31457d 100644
--- a/server/notification-providers/slack.js
+++ b/server/notification-providers/slack.js
@@ -1,6 +1,6 @@
 const NotificationProvider = require("./notification-provider");
 const axios = require("axios");
-const { setSettings, setting } = require("../util-server");
+const { setSettings, setting } = require("../util");
 const { getMonitorRelativeURL, UP, log } = require("../../src/util");
 const isUrl = require("is-url");
 
diff --git a/server/notification-providers/teams.js b/server/notification-providers/teams.js
index 5fd93afe2..6d1e5364c 100644
--- a/server/notification-providers/teams.js
+++ b/server/notification-providers/teams.js
@@ -1,6 +1,6 @@
 const NotificationProvider = require("./notification-provider");
 const axios = require("axios");
-const { setting } = require("../util-server");
+const { setting } = require("../util");
 const { DOWN, UP, getMonitorRelativeURL } = require("../../src/util");
 
 class Teams extends NotificationProvider {
diff --git a/server/notification.js b/server/notification.js
index 4e5e69dc2..60d06444b 100644
--- a/server/notification.js
+++ b/server/notification.js
@@ -103,7 +103,7 @@ const AmootSMS = require("./notification-providers/amootsms");
 const SMSPlanet = require("./notification-providers/sms-planet");
 const SpugPush = require("./notification-providers/spugpush");
 const SMSIR = require("./notification-providers/smsir");
-const { commandExists } = require("./util-server");
+const { commandExists } = require("./util");
 const Whatsapp360messenger = require("./notification-providers/360messenger");
 const Webpush = require("./notification-providers/Webpush");
 const HaloPSA = require("./notification-providers/HaloPSA");
diff --git a/server/routers/api-router.js b/server/routers/api-router.js
index 7b0882001..5dc0b73cd 100644
--- a/server/routers/api-router.js
+++ b/server/routers/api-router.js
@@ -1,11 +1,5 @@
 let express = require("express");
-const {
-    allowDevAllOrigin,
-    allowAllOrigin,
-    percentageToColor,
-    filterAndJoin,
-    sendHttpError,
-} = require("../util-server");
+const { allowDevAllOrigin, allowAllOrigin, percentageToColor, filterAndJoin, sendHttpError } = require("../util");
 const { R } = require("redbean-node");
 const apicache = require("../modules/apicache");
 const Monitor = require("../model/monitor");
diff --git a/server/routers/better-auth-router.ts b/server/routers/better-auth-router.ts
index dd67a06ef..8b8a79dee 100644
--- a/server/routers/better-auth-router.ts
+++ b/server/routers/better-auth-router.ts
@@ -5,8 +5,7 @@ import { R } from "redbean-node";
 import { log } from "../../src/util";
 
 // @ts-ignore
-import { allowDevOrigin } from "../util-server.js";
-import { generalErrorResponse } from "../util2";
+import { allowDevOrigin, generalErrorResponse } from "../util";
 
 let processingSetup = false;
 let _hasUser = false;
diff --git a/server/routers/status-page-router.js b/server/routers/status-page-router.js
index dea449c46..02e3f2ab2 100644
--- a/server/routers/status-page-router.js
+++ b/server/routers/status-page-router.js
@@ -2,7 +2,7 @@ let express = require("express");
 const apicache = require("../modules/apicache");
 const { UptimeKumaServer } = require("../uptime-kuma-server");
 const StatusPage = require("../model/status_page");
-const { allowDevAllOrigin, sendHttpError } = require("../util-server");
+const { allowDevAllOrigin, sendHttpError } = require("../util");
 const { R } = require("redbean-node");
 const { badgeConstants } = require("../../src/util");
 const { makeBadge } = require("badge-maker");
diff --git a/server/server.js b/server/server.js
index 1c2eefbb8..baee91275 100644
--- a/server/server.js
+++ b/server/server.js
@@ -3,6 +3,16 @@
  * node "server/server.js"
  * DO NOT require("./server") in other modules, it likely creates circular dependency!
  */
+import {
+    initDayjs,
+    getSettings,
+    setSettings,
+    setting,
+    checkLogin,
+    allowDevAllOrigin,
+    printServerUrls,
+    allowDevOrigin,
+} from "./util";
 import { getRandomInt, isDevEnv, log, sleep } from "../src/util";
 import { auth, createHeaders, doubleCheckPassword, getDisableAuthSession, getSessionFromHeaders } from "./better-auth";
 import { createBetterAuthRouter, needSetup } from "./routers/better-auth-router";
@@ -14,11 +24,7 @@ import * as fs from "node:fs";
 
 console.log("Welcome to Uptime Kuma");
 
-// As the log function need to use dayjs, it should be very top
-const dayjs = require("dayjs");
-dayjs.extend(require("dayjs/plugin/utc"));
-dayjs.extend(require("./modules/dayjs/plugin/timezone"));
-dayjs.extend(require("dayjs/plugin/customParseFormat"));
+initDayjs();
 
 // Load environment variables from `.env`
 try {
@@ -119,15 +125,6 @@ log.debug("server", "Importing Monitor");
 const Monitor = require("./model/monitor");
 
 log.debug("server", "Importing Settings");
-const {
-    getSettings,
-    setSettings,
-    setting,
-    checkLogin,
-    allowDevAllOrigin,
-    printServerUrls,
-    allowDevOrigin,
-} = require("./util-server");
 
 log.debug("server", "Importing Notification");
 const { Notification } = require("./notification");
diff --git a/server/setup-database.js b/server/setup-database.js
index 42342576a..8bb3d24c8 100644
--- a/server/setup-database.js
+++ b/server/setup-database.js
@@ -4,7 +4,7 @@ const expressStaticGzip = require("express-static-gzip");
 const fs = require("fs");
 const path = require("path");
 const Database = require("./database");
-const { allowDevAllOrigin, printServerUrls } = require("./util-server");
+const { allowDevAllOrigin, printServerUrls } = require("./util");
 const mysql = require("mysql2/promise");
 const { isSSL, sslKey, sslCert, sslKeyPassphrase } = require("./config");
 const https = require("https");
diff --git a/server/socket-handlers/chart-socket-handler.js b/server/socket-handlers/chart-socket-handler.js
index 5e1898e54..1b0443d3b 100644
--- a/server/socket-handlers/chart-socket-handler.js
+++ b/server/socket-handlers/chart-socket-handler.js
@@ -1,4 +1,4 @@
-const { checkLogin } = require("../util-server");
+const { checkLogin } = require("../util");
 const { UptimeCalculator } = require("../uptime-calculator");
 const { log } = require("../../src/util");
 
diff --git a/server/socket-handlers/cloudflared-socket-handler.js b/server/socket-handlers/cloudflared-socket-handler.js
index b14a51bf0..2e67311c4 100644
--- a/server/socket-handlers/cloudflared-socket-handler.js
+++ b/server/socket-handlers/cloudflared-socket-handler.js
@@ -1,4 +1,4 @@
-const { checkLogin, setSetting, setting } = require("../util-server");
+const { checkLogin, setSetting, setting } = require("../util");
 const { CloudflaredTunnel } = require("node-cloudflared-tunnel");
 const { UptimeKumaServer } = require("../uptime-kuma-server");
 const { log } = require("../../src/util");
diff --git a/server/socket-handlers/database-socket-handler.js b/server/socket-handlers/database-socket-handler.js
index 14677e35f..cf7433958 100644
--- a/server/socket-handlers/database-socket-handler.js
+++ b/server/socket-handlers/database-socket-handler.js
@@ -1,4 +1,4 @@
-const { checkLogin } = require("../util-server");
+const { checkLogin } = require("../util");
 const Database = require("../database");
 
 /**
diff --git a/server/socket-handlers/docker-socket-handler.js b/server/socket-handlers/docker-socket-handler.js
index 160b6cd1f..1af5dfb06 100644
--- a/server/socket-handlers/docker-socket-handler.js
+++ b/server/socket-handlers/docker-socket-handler.js
@@ -1,5 +1,5 @@
 const { sendDockerHostList } = require("../client");
-const { checkLogin } = require("../util-server");
+const { checkLogin } = require("../util");
 const { DockerHost } = require("../docker");
 const { log } = require("../../src/util");
 
diff --git a/server/socket-handlers/general-socket-handler.js b/server/socket-handlers/general-socket-handler.js
index fbb76e656..506eeb806 100644
--- a/server/socket-handlers/general-socket-handler.js
+++ b/server/socket-handlers/general-socket-handler.js
@@ -1,7 +1,7 @@
 const { log } = require("../../src/util");
 const { Settings } = require("../settings");
 const { sendInfo } = require("../client");
-const { checkLogin } = require("../util-server");
+const { checkLogin } = require("../util");
 const { games } = require("gamedig");
 const { testChrome } = require("../monitor-types/real-browser-monitor-type");
 const { getPM2ProcessList } = require("../util/pm2");
diff --git a/server/socket-handlers/maintenance-socket-handler.js b/server/socket-handlers/maintenance-socket-handler.js
index 457776c03..f989e3f78 100644
--- a/server/socket-handlers/maintenance-socket-handler.js
+++ b/server/socket-handlers/maintenance-socket-handler.js
@@ -1,4 +1,4 @@
-const { checkLogin } = require("../util-server");
+const { checkLogin } = require("../util");
 const { log } = require("../../src/util");
 const { R } = require("redbean-node");
 const apicache = require("../modules/apicache");
diff --git a/server/socket-handlers/proxy-socket-handler.js b/server/socket-handlers/proxy-socket-handler.js
index d83a19fbe..c1f185997 100644
--- a/server/socket-handlers/proxy-socket-handler.js
+++ b/server/socket-handlers/proxy-socket-handler.js
@@ -1,4 +1,4 @@
-const { checkLogin } = require("../util-server");
+const { checkLogin } = require("../util");
 const { Proxy } = require("../proxy");
 const { sendProxyList } = require("../client");
 const { UptimeKumaServer } = require("../uptime-kuma-server");
diff --git a/server/socket-handlers/remote-browser-socket-handler.js b/server/socket-handlers/remote-browser-socket-handler.js
index 0f0a25d95..30d8f750c 100644
--- a/server/socket-handlers/remote-browser-socket-handler.js
+++ b/server/socket-handlers/remote-browser-socket-handler.js
@@ -1,5 +1,5 @@
 const { sendRemoteBrowserList } = require("../client");
-const { checkLogin } = require("../util-server");
+const { checkLogin } = require("../util");
 const { RemoteBrowser } = require("../remote-browser");
 
 const { log } = require("../../src/util");
diff --git a/server/socket-handlers/status-page-socket-handler.js b/server/socket-handlers/status-page-socket-handler.js
index 9a1ce2b79..8102a67c0 100644
--- a/server/socket-handlers/status-page-socket-handler.js
+++ b/server/socket-handlers/status-page-socket-handler.js
@@ -1,5 +1,5 @@
 const { R } = require("redbean-node");
-const { checkLogin } = require("../util-server");
+const { checkLogin } = require("../util");
 const dayjs = require("dayjs");
 const { log } = require("../../src/util");
 const ImageDataURI = require("../image-data-uri");
diff --git a/server/util-server.js b/server/util.ts
similarity index 69%
rename from server/util-server.js
rename to server/util.ts
index 198bead38..eccf180e3 100644
--- a/server/util-server.js
+++ b/server/util.ts
@@ -1,4 +1,15 @@
+import dayjs from "dayjs";
+import customParseFormat from "dayjs/plugin/customParseFormat";
+import timezone from "dayjs/plugin/timezone";
+import utc from "dayjs/plugin/utc";
+import { ZodError } from "zod";
 import { checkLogin as betterAuthCheckLogin } from "./better-auth";
+import type { Request, Response } from "express";
+import type { SASLOptions } from "kafkajs";
+import type { TokenSet } from "openid-client";
+import type { Bean } from "redbean-node";
+import type { Server, Socket } from "socket.io";
+import type { TLSSocket } from "tls";
 
 const { R } = require("redbean-node");
 const { log, badgeConstants } = require("../src/util");
@@ -16,32 +27,28 @@ const {
         rfc2865: { file, attributes },
     },
 } = require("node-radius-utils");
-const dayjs = require("dayjs");
-dayjs.extend(require("dayjs/plugin/utc"));
 
-// SASLOptions used in JSDoc
-// eslint-disable-next-line no-unused-vars
-const { Kafka, SASLOptions } = require("kafkajs");
+const { Kafka } = require("kafkajs");
 const crypto = require("crypto");
 
 /**
  * Gets an Access Token from an oidc/oauth2 provider
- * @param {string} tokenEndpoint The token URI from the auth service provider
- * @param {string} clientId The oidc/oauth application client id
- * @param {string} clientSecret The oidc/oauth application client secret
- * @param {string} scope The scope(s) for which the token should be issued for
- * @param {string} audience The audience for which the token should be issued for
- * @param {string} authMethod The method used to send the credentials. Default client_secret_basic
- * @returns {Promise<oidc.TokenSet>} TokenSet promise if the token request was successful
+ * @param tokenEndpoint The token URI from the auth service provider
+ * @param clientId The oidc/oauth application client id
+ * @param clientSecret The oidc/oauth application client secret
+ * @param scope The scope(s) for which the token should be issued for
+ * @param audience The audience for which the token should be issued for
+ * @param authMethod The method used to send the credentials. Default client_secret_basic
+ * @returns TokenSet promise if the token request was successful
  */
-exports.getOidcTokenClientCredentials = async (
-    tokenEndpoint,
-    clientId,
-    clientSecret,
-    scope,
-    audience,
-    authMethod = "client_secret_basic"
-) => {
+export async function getOidcTokenClientCredentials(
+    tokenEndpoint: string,
+    clientId: string,
+    clientSecret: string,
+    scope: string,
+    audience: string,
+    authMethod: string = "client_secret_basic"
+): Promise<TokenSet> {
     const oauthProvider = new oidc.Issuer({ token_endpoint: tokenEndpoint });
     let client = new oauthProvider.Client({
         client_id: clientId,
@@ -62,23 +69,29 @@ exports.getOidcTokenClientCredentials = async (
         grantParams.audience = audience;
     }
     return await client.grant(grantParams);
-};
+}
 
 /**
  * Monitor Kafka using Producer
- * @param {string[]} brokers List of kafka brokers to connect, host and
+ * @param brokers List of kafka brokers to connect, host and
  * port joined by ':'
- * @param {string} topic Topic name to produce into
- * @param {string} message Message to produce
- * @param {object} options Kafka client options. Contains ssl, clientId,
+ * @param topic Topic name to produce into
+ * @param message Message to produce
+ * @param options Kafka client options. Contains ssl, clientId,
  * allowAutoTopicCreation and interval (interval defaults to 20,
  * allowAutoTopicCreation defaults to false, clientId defaults to
  * "Uptime-Kuma" and ssl defaults to false)
- * @param {SASLOptions} saslOptions Options for kafka client
+ * @param saslOptions Options for kafka client
  * Authentication (SASL) (defaults to {})
- * @returns {Promise<string>} Status message
+ * @returns Status message
  */
-exports.kafkaProducerAsync = function (brokers, topic, message, options = {}, saslOptions = {}) {
+export function kafkaProducerAsync(
+    brokers: string[],
+    topic: string,
+    message: string,
+    options: object = {},
+    saslOptions: SASLOptions = {}
+): Promise<string> {
     return new Promise((resolve, reject) => {
         const {
             interval = 20,
@@ -168,15 +181,15 @@ exports.kafkaProducerAsync = function (brokers, topic, message, options = {}, sa
             }
         });
     });
-};
+}
 
 /**
  * Use NTLM Auth for a http request.
- * @param {object} options The http request options
- * @param {object} ntlmOptions The auth options
- * @returns {Promise<(string[] | object[] | object)>} NTLM response
+ * @param options The http request options
+ * @param ntlmOptions The auth options
+ * @returns NTLM response
  */
-exports.httpNtlm = function (options, ntlmOptions) {
+export function httpNtlm(options: object, ntlmOptions: object): Promise<string[] | object[] | object> {
     return new Promise((resolve, reject) => {
         let client = NtlmClient(ntlmOptions);
 
@@ -188,30 +201,30 @@ exports.httpNtlm = function (options, ntlmOptions) {
                 reject(err);
             });
     });
-};
+}
 
 /**
  * Query radius server
- * @param {string} hostname Hostname of radius server
- * @param {string} username Username to use
- * @param {string} password Password to use
- * @param {string} calledStationId ID of called station
- * @param {string} callingStationId ID of calling station
- * @param {string} secret Secret to use
- * @param {number} port Port to contact radius server on
- * @param {number} timeout Timeout for connection to use
- * @returns {Promise<any>} Response from server
+ * @param hostname Hostname of radius server
+ * @param username Username to use
+ * @param password Password to use
+ * @param calledStationId ID of called station
+ * @param callingStationId ID of calling station
+ * @param secret Secret to use
+ * @param port Port to contact radius server on
+ * @param timeout Timeout for connection to use
+ * @returns Response from server
  */
-exports.radius = function (
-    hostname,
-    username,
-    password,
-    calledStationId,
-    callingStationId,
-    secret,
-    port = 1812,
-    timeout = 2500
-) {
+export function radius(
+    hostname: string,
+    username: string,
+    password: string,
+    calledStationId: string,
+    callingStationId: string,
+    secret: string,
+    port: number = 1812,
+    timeout: number = 2500
+): Promise<{ code: string }> {
     const client = new RadiusClient({
         host: hostname,
         hostPort: port,
@@ -247,47 +260,47 @@ exports.radius = function (
                 throw enhancedError;
             }
         });
-};
+}
 
 /**
  * Retrieve value of setting based on key
- * @param {string} key Key of setting to retrieve
- * @returns {Promise<any>} Value
+ * @param key Key of setting to retrieve
+ * @returns Value
  * @deprecated Use await Settings.get(key)
  */
-exports.setting = async function (key) {
+export async function setting(key: string): Promise<Bean | null> {
     return await Settings.get(key);
-};
+}
 
 /**
  * Sets the specified setting to specified value
- * @param {string} key Key of setting to set
- * @param {any} value Value to set to
- * @param {?string} type Type of setting
- * @returns {Promise<void>}
+ * @param key Key of setting to set
+ * @param value Value to set to
+ * @param type Type of setting
+ * @returns
  */
-exports.setSetting = async function (key, value, type = null) {
+export async function setSetting(key: string, value: unknown, type: string | null = null): Promise<void> {
     await Settings.set(key, value, type);
-};
+}
 
 /**
  * Get settings based on type
- * @param {string} type The type of setting
- * @returns {Promise<Bean>} Settings of requested type
+ * @param type The type of setting
+ * @returns Settings of requested type
  */
-exports.getSettings = async function (type) {
+export async function getSettings(type: string): Promise<Record<string, unknown>> {
     return await Settings.getSettings(type);
-};
+}
 
 /**
  * Set settings based on type
- * @param {string} type Type of settings to set
- * @param {object} data Values of settings
- * @returns {Promise<void>}
+ * @param type Type of settings to set
+ * @param data Values of settings
+ * @returns
  */
-exports.setSettings = async function (type, data) {
+export async function setSettings(type: string, data: object): Promise<void> {
     await Settings.setSettings(type, data);
-};
+}
 
 // ssl-checker by @dyaa
 //https://github.com/dyaa/ssl-checker/blob/master/src/index.ts
@@ -302,18 +315,17 @@ const getDaysBetween = (validFrom, validTo) => Math.round(Math.abs(+validFrom -
 
 /**
  * Get days remaining from a time range
- * @param {Date} validFrom Start date
- * @param {Date} validTo End date
- * @returns {number} Number of days remaining
+ * @param validFrom Start date
+ * @param validTo End date
+ * @returns Number of days remaining
  */
-const getDaysRemaining = (validFrom, validTo) => {
+export function getDaysRemaining(validFrom: Date, validTo: Date): number {
     const daysRemaining = getDaysBetween(validFrom, validTo);
     if (new Date(validTo).getTime() < new Date().getTime()) {
         return -daysRemaining;
     }
     return daysRemaining;
-};
-module.exports.getDaysRemaining = getDaysRemaining;
+}
 
 /**
  * Fix certificate info for display
@@ -366,10 +378,10 @@ const parseCertificateInfo = function (info) {
 
 /**
  * Check if certificate is valid
- * @param {tls.TLSSocket} socket TLSSocket, which may or may not be connected
- * @returns {null | {valid: boolean, certInfo: object}} Object containing certificate information
+ * @param socket TLSSocket, which may or may not be connected
+ * @returns} Object containing certificate information
  */
-exports.checkCertificate = function (socket) {
+export function checkCertificate(socket: TLSSocket): null | { valid: boolean; certInfo: object } {
     let certInfoStartTime = dayjs().valueOf();
 
     // Return null if there is no socket
@@ -391,16 +403,16 @@ exports.checkCertificate = function (socket) {
         valid: valid,
         certInfo: parsedInfo,
     };
-};
+}
 
 /**
  * Checks if the certificate is valid for the provided hostname.
  * Defaults to true if feature `X509Certificate` is not available, or input is not valid.
- * @param {Buffer} certBuffer - The certificate buffer.
- * @param {string} hostname - The hostname to compare against.
- * @returns {boolean} True if the certificate is valid for the provided hostname, false otherwise.
+ * @param certBuffer - The certificate buffer.
+ * @param hostname - The hostname to compare against.
+ * @returns True if the certificate is valid for the provided hostname, false otherwise.
  */
-exports.checkCertificateHostname = function (certBuffer, hostname) {
+export function checkCertificateHostname(certBuffer: Buffer, hostname: string): boolean {
     let X509Certificate;
     try {
         X509Certificate = require("node:crypto").X509Certificate;
@@ -415,15 +427,15 @@ exports.checkCertificateHostname = function (certBuffer, hostname) {
 
     let certObject = new X509Certificate(certBuffer);
     return certObject.checkHost(hostname) !== undefined;
-};
+}
 
 /**
  * Check if the provided status code is within the accepted ranges
- * @param {number} status The status code to check
- * @param {string[]} acceptedCodes An array of accepted status codes
- * @returns {boolean} True if status code within range, false otherwise
+ * @param status The status code to check
+ * @param acceptedCodes An array of accepted status codes
+ * @returns True if status code within range, false otherwise
  */
-exports.checkStatusCode = function (status, acceptedCodes) {
+export function checkStatusCode(status: number, acceptedCodes: string[]): boolean {
     if (acceptedCodes == null || acceptedCodes.length === 0) {
         return false;
     }
@@ -450,15 +462,15 @@ exports.checkStatusCode = function (status, acceptedCodes) {
     }
 
     return false;
-};
+}
 
 /**
  * Get total number of clients in room
- * @param {Server} io Socket server instance
- * @param {string} roomName Name of room to check
- * @returns {number} Total clients in room
+ * @param io Socket server instance
+ * @param roomName Name of room to check
+ * @returns Total clients in room
  */
-exports.getTotalClientInRoom = (io, roomName) => {
+export function getTotalClientInRoom(io: Server, roomName: string): number {
     const sockets = io.sockets;
 
     if (!sockets) {
@@ -478,104 +490,104 @@ exports.getTotalClientInRoom = (io, roomName) => {
     } else {
         return 0;
     }
-};
+}
 
 /**
  * @deprecated Use allowDevOrigin
  * Allow CORS all origins if development
- * @param {object} res Response object from axios
- * @returns {void}
+ * @param res Response object from axios
+ * @returns
  */
-exports.allowDevAllOrigin = (res) => {
+export function allowDevAllOrigin(res: object): void {
     if (process.env.NODE_ENV === "development") {
-        exports.allowAllOrigin(res);
+        allowAllOrigin(res);
     }
-};
+}
 
 /**
  * @deprecated Use allowOrigin
  * Allow CORS all origins
- * @param {object} res Response object from axios
- * @returns {void}
+ * @param res Response object from axios
+ * @returns
  */
-exports.allowAllOrigin = (res) => {
+export function allowAllOrigin(res: object): void {
     res.header("Access-Control-Allow-Origin", "*");
     res.header("Access-Control-Allow-Methods", "GET, PUT, POST, DELETE, OPTIONS");
     res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
-};
+}
 
 /**
  * Allow CORS all origins if development
- * @param {Request} req Express request object
- * @param {Response} res Express response object
- * @returns {void}
+ * @param req Express request object
+ * @param res Express response object
+ * @returns
  */
-exports.allowDevOrigin = (req, res) => {
+export function allowDevOrigin(req: Request, res: Response): void {
     if (process.env.NODE_ENV === "development") {
-        exports.allowOrigin(req, res);
+        allowOrigin(req, res);
     }
-};
+}
 
 /**
  * Allow CORS all origins
  * Since Allow-Credentials is set to true, the Access-Control-Allow-Origin cannot be *, so we will set it to the request origin.
- * @param {Request} req Express request object
- * @param {Response} res Response object
- * @returns {void}
+ * @param req Express request object
+ * @param res Response object
+ * @returns
  */
-exports.allowOrigin = (req, res) => {
+export function allowOrigin(req: Request, res: Response): void {
     res.header("Access-Control-Allow-Origin", req.get("origin"));
     res.header("Access-Control-Allow-Methods", "GET, PUT, POST, DELETE, OPTIONS");
     res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
     res.header("Access-Control-Allow-Credentials", "true");
-};
+}
 
 /**
  * @deprecated Use better-auth's checkLogin
  * Check if a user is logged in
- * @param {Socket} socket Socket instance
- * @returns {void}
+ * @param socket Socket instance
+ * @returns
  * @throws The user is not logged in
  */
-exports.checkLogin = (socket) => {
+export function checkLogin(socket: Socket): void {
     betterAuthCheckLogin(socket);
-};
+}
 
 /**
  * Returns a color code in hex format based on a given percentage:
  * 0% => hue = 10 => red
  * 100% => hue = 90 => green
- * @param {number} percentage float, 0 to 1
- * @param {number} maxHue Maximum hue - int
- * @param {number} minHue Minimum hue - int
- * @returns {string} Color in hex
+ * @param percentage float, 0 to 1
+ * @param maxHue Maximum hue - int
+ * @param minHue Minimum hue - int
+ * @returns Color in hex
  */
-exports.percentageToColor = (percentage, maxHue = 90, minHue = 10) => {
+export function percentageToColor(percentage: number, maxHue: number = 90, minHue: number = 10): string {
     const hue = percentage * (maxHue - minHue) + minHue;
     try {
         return chroma(`hsl(${hue}, 90%, 40%)`).hex();
     } catch (err) {
         return badgeConstants.naColor;
     }
-};
+}
 
 /**
  * Joins and array of string to one string after filtering out empty values
- * @param {string[]} parts Strings to join
- * @param {string} connector Separator for joined strings
- * @returns {string} Joined strings
+ * @param parts Strings to join
+ * @param connector Separator for joined strings
+ * @returns Joined strings
  */
-exports.filterAndJoin = (parts, connector = "") => {
+export function filterAndJoin(parts: string[], connector: string = ""): string {
     return parts.filter((part) => !!part && part !== "").join(connector);
-};
+}
 
 /**
  * Send an Error response
- * @param {object} res Express response object
- * @param {string} msg Message to send
- * @returns {void}
+ * @param res Express response object
+ * @param msg Message to send
+ * @returns
  */
-module.exports.sendHttpError = (res, msg = "") => {
+export function sendHttpError(res: object, msg: string = ""): void {
     if (msg.includes("SQLITE_BUSY") || msg.includes("SQLITE_LOCKED")) {
         res.status(503).json({
             status: "fail",
@@ -592,16 +604,16 @@ module.exports.sendHttpError = (res, msg = "") => {
             msg: msg,
         });
     }
-};
+}
 
 /**
  * Convert timezone of time object
- * @param {object} obj Time object to update
- * @param {string} timezone New timezone to set
- * @param {boolean} timeObjectToUTC Convert time object to UTC
- * @returns {object} Time object with updated timezone
+ * @param obj Time object to update
+ * @param timezone New timezone to set
+ * @param timeObjectToUTC Convert time object to UTC
+ * @returns Time object with updated timezone
  */
-function timeObjectConvertTimezone(obj, timezone, timeObjectToUTC = true) {
+function timeObjectConvertTimezone(obj: object, timezone: string, timeObjectToUTC: boolean = true): object {
     let offsetString;
 
     if (timezone) {
@@ -641,29 +653,29 @@ function timeObjectConvertTimezone(obj, timezone, timeObjectToUTC = true) {
 
 /**
  * Convert time object to UTC
- * @param {object} obj Object to convert
- * @param {string} timezone Timezone of time object
- * @returns {object} Updated time object
+ * @param obj Object to convert
+ * @param timezone Timezone of time object
+ * @returns Updated time object
  */
-module.exports.timeObjectToUTC = (obj, timezone = undefined) => {
+export function timeObjectToUTC(obj: object, timezone: string = undefined): object {
     return timeObjectConvertTimezone(obj, timezone, true);
-};
+}
 
 /**
  * Convert time object to local time
- * @param {object} obj Object to convert
- * @param {string} timezone Timezone to convert to
- * @returns {object} Updated object
+ * @param obj Object to convert
+ * @param timezone Timezone to convert to
+ * @returns Updated object
  */
-module.exports.timeObjectToLocal = (obj, timezone = undefined) => {
+export function timeObjectToLocal(obj: object, timezone: string = undefined): object {
     return timeObjectConvertTimezone(obj, timezone, false);
-};
+}
 
 /**
  * Returns an array of SHA256 fingerprints for all known root certificates.
- * @returns {Set} A set of SHA256 fingerprints.
+ * @returns A set of SHA256 fingerprints.
  */
-module.exports.rootCertificatesFingerprints = () => {
+export function rootCertificatesFingerprints(): Set<unknown> {
     let fingerprints = tls.rootCertificates.map((cert) => {
         let certLines = cert.split("\n");
         certLines.shift();
@@ -688,48 +700,44 @@ module.exports.rootCertificatesFingerprints = () => {
     ); // ISRG X2 cross-signed with ISRG X1
 
     return new Set(fingerprints);
-};
+}
 
-module.exports.SHAKE256_LENGTH = 16;
+export const SHAKE256_LENGTH = 16;
 
 /**
- * @param {string} data The data to be hashed
- * @param {number} len Output length of the hash
- * @returns {string} The hashed data in hex format
+ * @param data The data to be hashed
+ * @param len Output length of the hash
+ * @returns The hashed data in hex format
  */
-module.exports.shake256 = (data, len) => {
+export function shake256(data: string, len: number): string {
     if (!data) {
         return "";
     }
     return crypto.createHash("shake256", { outputLength: len }).update(data).digest("hex");
-};
+}
 
 /**
  * Non await sleep
  * Source: https://stackoverflow.com/questions/59099454/is-there-a-way-to-call-sleep-without-await-keyword
- * @param {number} n Milliseconds to wait
- * @returns {void}
+ * @param n Milliseconds to wait
+ * @returns
  */
-module.exports.wait = (n) => {
+export function wait(n: number): void {
     Atomics.wait(new Int32Array(new SharedArrayBuffer(4)), 0, 0, n);
-};
+}
 
 // For unit test, export functions
-if (process.env.TEST_BACKEND) {
-    module.exports.__test = {
-        parseCertificateInfo,
-    };
-    module.exports.__getPrivateFunction = (functionName) => {
-        return module.exports.__test[functionName];
-    };
+export const __test = process.env.TEST_BACKEND ? { parseCertificateInfo } : undefined;
+export function __getPrivateFunction(functionName) {
+    return __test?.[functionName];
 }
 
 /**
  * Generates an abort signal with the specified timeout.
- * @param {number} timeoutMs - The timeout in milliseconds.
- * @returns {AbortSignal | null} - The generated abort signal, or null if not supported.
+ * @param timeoutMs - The timeout in milliseconds.
+ * @returns - The generated abort signal, or null if not supported.
  */
-module.exports.axiosAbortSignal = (timeoutMs) => {
+export function axiosAbortSignal(timeoutMs: number): AbortSignal | null {
     try {
         // Just in case, as 0 timeout here will cause the request to be aborted immediately
         if (!timeoutMs || timeoutMs <= 0) {
@@ -748,41 +756,39 @@ module.exports.axiosAbortSignal = (timeoutMs) => {
             return null;
         }
     }
-};
+}
 
 /**
  * Async version of fs.existsSync
- * @param {PathLike} path File path
- * @returns {Promise<boolean>} True if file exists, false otherwise
+ * @param path File path
+ * @returns True if file exists, false otherwise
  */
-function fsExists(path) {
+export function fsExists(path: string | Buffer): Promise<boolean> {
     return new Promise(function (resolve, reject) {
         exists(path, function (exists) {
             resolve(exists);
         });
     });
 }
-module.exports.fsExists = fsExists;
 
 /**
  * Encode user and password to Base64 encoding
  * for HTTP "basic" auth, as per RFC-7617
- * @param {string|null} user - The username (defaults to empty string if null/undefined)
- * @param {string|null} pass - The password (defaults to empty string if null/undefined)
- * @returns {string} Encoded Base64 string
+ * @param user - The username (defaults to empty string if null/undefined)
+ * @param pass - The password (defaults to empty string if null/undefined)
+ * @returns Encoded Base64 string
  */
-function encodeBase64(user, pass) {
+export function encodeBase64(user: string | null, pass: string | null): string {
     return Buffer.from(`${user || ""}:${pass || ""}`).toString("base64");
 }
-module.exports.encodeBase64 = encodeBase64;
 
 /**
  * checks certificate chain for expiring certificates
- * @param {object} monitor - The monitor object
- * @param {object} tlsInfoObject Information about certificate
- * @returns {Promise<void>}
+ * @param monitor - The monitor object
+ * @param tlsInfoObject Information about certificate
+ * @returns
  */
-async function checkCertExpiryNotifications(monitor, tlsInfoObject) {
+export async function checkCertExpiryNotifications(monitor: object, tlsInfoObject: object): Promise<void> {
     if (!tlsInfoObject || !tlsInfoObject.certInfo || !tlsInfoObject.certInfo.daysRemaining) {
         return;
     }
@@ -837,15 +843,14 @@ async function checkCertExpiryNotifications(monitor, tlsInfoObject) {
         }
     }
 }
-module.exports.checkCertExpiryNotifications = checkCertExpiryNotifications;
 
 /**
  * By default, command-exists will throw a null error if the command does not exist, which is ugly. The function makes it better.
  * Read more: https://github.com/mathisonian/command-exists/issues/22
- * @param {string} command Command to check
- * @returns {Promise<boolean>} True if command exists, false otherwise
+ * @param command Command to check
+ * @returns True if command exists, false otherwise
  */
-async function commandExists(command) {
+export async function commandExists(command: string): Promise<boolean> {
     try {
         await require("command-exists")(command);
         return true;
@@ -853,19 +858,18 @@ async function commandExists(command) {
         return false;
     }
 }
-module.exports.commandExists = commandExists;
 
 /**
  * Log the server's listening URLs, similar to Vite's dev server output.
  * When no hostname is specified (bound to all interfaces), it prints
  * localhost plus every non-internal network address.
- * @param {string} tag Log tag (e.g. "server", "setup-database")
- * @param {number} port Port number
- * @param {string} hostname Bound hostname, if any
- * @param {boolean} isHTTPS Whether the server is using HTTPS
- * @returns {void}
+ * @param tag Log tag (e.g. "server", "setup-database")
+ * @param port Port number
+ * @param hostname Bound hostname, if any
+ * @param isHTTPS Whether the server is using HTTPS
+ * @returns
  */
-module.exports.printServerUrls = (tag, port, hostname, isHTTPS = false) => {
+export function printServerUrls(tag: string, port: number, hostname: string, isHTTPS: boolean = false): void {
     try {
         // If hostname is specified, just print that one.
         if (hostname) {
@@ -909,19 +913,58 @@ module.exports.printServerUrls = (tag, port, hostname, isHTTPS = false) => {
     } catch (e) {
         log.error(tag, "Error printing server URLs: " + e.message);
     }
-};
+}
 
 /**
  * Construct a URL a bit more safely
- * @param {boolean} isHTTPS Whether the URL should use HTTPS protocol
- * @param {string} hostname The hostname to use in the URL
- * @param {number} port The port
- * @returns {string} The constructed URL as a string
+ * @param isHTTPS Whether the URL should use HTTPS protocol
+ * @param hostname The hostname to use in the URL
+ * @param port The port
+ * @returns The constructed URL as a string
  */
-function createURL(isHTTPS, hostname, port = 80) {
+function createURL(isHTTPS: boolean, hostname: string, port: number = 80): string {
     const url = new URL((isHTTPS ? "https" : "http") + `://` + hostname);
     url.port = String(port);
 
     // Prefer origin if available, it doesn't contain the trailing slash
     return url.origin || url.toString();
 }
+
+/**
+ * Extend dayjs with the plugins the backend uses
+ * @returns The shared dayjs instance
+ */
+export function initDayjs(): object {
+    dayjs.extend(utc);
+    dayjs.extend(timezone);
+    dayjs.extend(customParseFormat);
+    return dayjs;
+}
+
+/**
+ * @param res Express response
+ * @param e Any error
+ * @returns
+ */
+export function generalErrorResponse(res: Response, e: unknown): void {
+    if (e instanceof ZodError) {
+        let message = "";
+        for (const issue of e.issues) {
+            message += `${issue.path.join(".")}: ${issue.message}\n`;
+        }
+        res.status(400).json({
+            ok: false,
+            msg: message,
+        });
+    } else if (e instanceof Error) {
+        res.status(400).json({
+            ok: false,
+            msg: e.message,
+        });
+    } else {
+        res.status(400).json({
+            ok: false,
+            msg: "Unknown error",
+        });
+    }
+}
diff --git a/server/util2.ts b/server/util2.ts
deleted file mode 100644
index 8d06d86f1..000000000
--- a/server/util2.ts
+++ /dev/null
@@ -1,29 +0,0 @@
-import { ZodError } from "zod";
-import { Response } from "express";
-
-/**
- * @param res Express response
- * @param e Any error
- */
-export function generalErrorResponse(res: Response, e: unknown) {
-    if (e instanceof ZodError) {
-        let message = "";
-        for (const issue of e.issues) {
-            message += `${issue.path.join(".")}: ${issue.message}\n`;
-        }
-        res.status(400).json({
-            ok: false,
-            msg: message,
-        });
-    } else if (e instanceof Error) {
-        res.status(400).json({
-            ok: false,
-            msg: e.message,
-        });
-    } else {
-        res.status(400).json({
-            ok: false,
-            msg: "Unknown error",
-        });
-    }
-}
diff --git a/server/utils/simple-migration-server.js b/server/utils/simple-migration-server.js
index 524584035..c40eb3d30 100644
--- a/server/utils/simple-migration-server.js
+++ b/server/utils/simple-migration-server.js
@@ -1,6 +1,6 @@
 const express = require("express");
 const http = require("node:http");
-const { printServerUrls } = require("../util-server");
+const { printServerUrls } = require("../util");
 
 /**
  * SimpleMigrationServer
diff --git a/src/main.js b/src/main.js
index 4c8858367..89eea7aad 100644
--- a/src/main.js
+++ b/src/main.js
@@ -16,14 +16,9 @@ import theme from "./mixins/theme";
 import lang from "./mixins/lang";
 import { router } from "./router";
 import { appName } from "./util.ts";
-import dayjs from "dayjs";
-import timezone from "./modules/dayjs/plugin/timezone";
-import utc from "dayjs/plugin/utc";
-import relativeTime from "dayjs/plugin/relativeTime";
-import { loadToastSettings } from "./util-frontend";
-dayjs.extend(utc);
-dayjs.extend(timezone);
-dayjs.extend(relativeTime);
+import { initDayjs, loadToastSettings } from "./util-frontend";
+
+initDayjs();
 
 const app = createApp({
     mixins: [socket, theme, mobile, datetime, publicMixin, lang],
diff --git a/src/mixins/socket.js b/src/mixins/socket.js
index f215e05d1..98c8feba8 100644
--- a/src/mixins/socket.js
+++ b/src/mixins/socket.js
@@ -6,7 +6,7 @@ import dayjs from "dayjs";
 import mitt from "mitt";
 
 import { DOWN, MAINTENANCE, PENDING, UP } from "../util.ts";
-import { getToastSuccessTimeout, getToastErrorTimeout } from "../util-frontend.js";
+import { getToastSuccessTimeout, getToastErrorTimeout } from "../util-frontend";
 import { BeatVersionThrottle } from "../beat-version-throttle";
 import { applyBeat, applyLatestBeats, beatStatusEntry } from "../beat-state";
 import { logout as betterAuthLogout } from "../auth-client";
diff --git a/src/modules/dayjs/constant.js b/src/modules/dayjs/constant.js
deleted file mode 100644
index 741a623b7..000000000
--- a/src/modules/dayjs/constant.js
+++ /dev/null
@@ -1,25 +0,0 @@
-export let SECONDS_A_MINUTE = 60;
-export let SECONDS_A_HOUR = SECONDS_A_MINUTE * 60;
-export let SECONDS_A_DAY = SECONDS_A_HOUR * 24;
-export let SECONDS_A_WEEK = SECONDS_A_DAY * 7;
-export let MILLISECONDS_A_SECOND = 1e3;
-export let MILLISECONDS_A_MINUTE = SECONDS_A_MINUTE * MILLISECONDS_A_SECOND;
-export let MILLISECONDS_A_HOUR = SECONDS_A_HOUR * MILLISECONDS_A_SECOND;
-export let MILLISECONDS_A_DAY = SECONDS_A_DAY * MILLISECONDS_A_SECOND;
-export let MILLISECONDS_A_WEEK = SECONDS_A_WEEK * MILLISECONDS_A_SECOND; // English locales
-
-export let MS = "millisecond";
-export let S = "second";
-export let MIN = "minute";
-export let H = "hour";
-export let D = "day";
-export let W = "week";
-export let M = "month";
-export let Q = "quarter";
-export let Y = "year";
-export let DATE = "date";
-export let FORMAT_DEFAULT = "YYYY-MM-DDTHH:mm:ssZ";
-export let INVALID_DATE_STRING = "Invalid Date"; // regex
-
-export let REGEX_PARSE = /^(\d{4})[-/]?(\d{1,2})?[-/]?(\d{0,2})[Tt\s]*(\d{1,2})?:?(\d{1,2})?:?(\d{1,2})?[.:]?(\d+)?$/;
-export let REGEX_FORMAT = /\[([^\]]+)]|Y{1,4}|M{1,4}|D{1,2}|d{1,4}|H{1,2}|h{1,2}|a|A|m{1,2}|s{1,2}|Z{1,2}|SSS/g;
diff --git a/src/modules/dayjs/plugin/timezone/index.d.ts b/src/modules/dayjs/plugin/timezone/index.d.ts
deleted file mode 100644
index ce8e98e1d..000000000
--- a/src/modules/dayjs/plugin/timezone/index.d.ts
+++ /dev/null
@@ -1,20 +0,0 @@
-import { PluginFunc, ConfigType } from "dayjs/esm";
-
-declare const plugin: PluginFunc;
-export = plugin;
-
-declare module "dayjs/esm" {
-    interface Dayjs {
-        tz(timezone?: string, keepLocalTime?: boolean): Dayjs;
-        offsetName(type?: "short" | "long"): string | undefined;
-    }
-
-    interface DayjsTimezone {
-        (date: ConfigType, timezone?: string): Dayjs;
-        (date: ConfigType, format: string, timezone?: string): Dayjs;
-        guess(): string;
-        setDefault(timezone?: string): void;
-    }
-
-    const tz: DayjsTimezone;
-}
diff --git a/src/modules/dayjs/plugin/timezone/index.js b/src/modules/dayjs/plugin/timezone/index.js
deleted file mode 100644
index c377c006e..000000000
--- a/src/modules/dayjs/plugin/timezone/index.js
+++ /dev/null
@@ -1,204 +0,0 @@
-/**
- * Copy from node_modules/dayjs/plugin/timezone.js
- * Try to fix https://github.com/louislam/uptime-kuma/issues/2318
- * Source: https://github.com/iamkun/dayjs/tree/dev/src/plugin/utc
- * License: MIT
- */
-import { MIN, MS } from "../../constant";
-let typeToPos = {
-    year: 0,
-    month: 1,
-    day: 2,
-    hour: 3,
-    minute: 4,
-    second: 5,
-}; // Cache time-zone lookups from Intl.DateTimeFormat,
-// as it is a *very* slow method.
-
-let dtfCache = {};
-
-let getDateTimeFormat = function getDateTimeFormat(timezone, options) {
-    if (options === void 0) {
-        options = {};
-    }
-
-    let timeZoneName = options.timeZoneName || "short";
-    let key = timezone + "|" + timeZoneName;
-    let dtf = dtfCache[key];
-
-    if (!dtf) {
-        dtf = new Intl.DateTimeFormat("en-US", {
-            hour12: false,
-            timeZone: timezone,
-            year: "numeric",
-            month: "2-digit",
-            day: "2-digit",
-            hour: "2-digit",
-            minute: "2-digit",
-            second: "2-digit",
-            timeZoneName: timeZoneName,
-        });
-        dtfCache[key] = dtf;
-    }
-
-    return dtf;
-};
-
-export default (function (o, c, d) {
-    let defaultTimezone;
-
-    let makeFormatParts = function makeFormatParts(timestamp, timezone, options) {
-        if (options === void 0) {
-            options = {};
-        }
-
-        let date = new Date(timestamp);
-        let dtf = getDateTimeFormat(timezone, options);
-        return dtf.formatToParts(date);
-    };
-
-    let tzOffset = function tzOffset(timestamp, timezone) {
-        let formatResult = makeFormatParts(timestamp, timezone);
-        let filled = [];
-
-        for (let i = 0; i < formatResult.length; i += 1) {
-            let _formatResult$i = formatResult[i];
-            let type = _formatResult$i.type;
-            let value = _formatResult$i.value;
-            let pos = typeToPos[type];
-
-            if (pos >= 0) {
-                filled[pos] = parseInt(value, 10);
-            }
-        }
-
-        let hour = filled[3]; // Workaround for the same behavior in different node version
-        // https://github.com/nodejs/node/issues/33027
-
-        /* istanbul ignore next */
-
-        let fixedHour = hour === 24 ? 0 : hour;
-        let utcString =
-            filled[0] +
-            "-" +
-            filled[1] +
-            "-" +
-            filled[2] +
-            " " +
-            fixedHour +
-            ":" +
-            filled[4] +
-            ":" +
-            filled[5] +
-            ":000";
-        let utcTs = d.utc(utcString).valueOf();
-        let asTS = +timestamp;
-        let over = asTS % 1000;
-        asTS -= over;
-        return (utcTs - asTS) / (60 * 1000);
-    }; // find the right offset a given local time. The o input is our guess, which determines which
-    // offset we'll pick in ambiguous cases (e.g. there are two 3 AMs b/c Fallback DST)
-    // https://github.com/moment/luxon/blob/master/src/datetime.js#L76
-
-    let fixOffset = function fixOffset(localTS, o0, tz) {
-        // Our UTC time is just a guess because our offset is just a guess
-        let utcGuess = localTS - o0 * 60 * 1000; // Test whether the zone matches the offset for this ts
-
-        let o2 = tzOffset(utcGuess, tz); // If so, offset didn't change and we're done
-
-        if (o0 === o2) {
-            return [utcGuess, o0];
-        } // If not, change the ts by the difference in the offset
-
-        utcGuess -= (o2 - o0) * 60 * 1000; // If that gives us the local time we want, we're done
-
-        let o3 = tzOffset(utcGuess, tz);
-
-        if (o2 === o3) {
-            return [utcGuess, o2];
-        } // If it's different, we're in a hole time.
-        // The offset has changed, but the we don't adjust the time
-
-        return [localTS - Math.min(o2, o3) * 60 * 1000, Math.max(o2, o3)];
-    };
-
-    let proto = c.prototype;
-
-    proto.tz = function (timezone, keepLocalTime) {
-        if (timezone === void 0) {
-            timezone = defaultTimezone;
-        }
-
-        let oldOffset = this.utcOffset();
-        let date = this.toDate();
-        let target = date
-            .toLocaleString("en-US", {
-                timeZone: timezone,
-            })
-            .replace("\u202f", " ");
-        let diff = Math.round((date - new Date(target)) / 1000 / 60);
-        let ins = d(target)
-            .$set(MS, this.$ms)
-            .utcOffset(-Math.round(date.getTimezoneOffset() / 15) * 15 - diff, true);
-
-        if (keepLocalTime) {
-            let newOffset = ins.utcOffset();
-            ins = ins.add(oldOffset - newOffset, MIN);
-        }
-
-        ins.$x.$timezone = timezone;
-        return ins;
-    };
-
-    proto.offsetName = function (type) {
-        // type: short(default) / long
-        let zone = this.$x.$timezone || d.tz.guess();
-        let result = makeFormatParts(this.valueOf(), zone, {
-            timeZoneName: type,
-        }).find(function (m) {
-            return m.type.toLowerCase() === "timezonename";
-        });
-        return result && result.value;
-    };
-
-    let oldStartOf = proto.startOf;
-
-    proto.startOf = function (units, startOf) {
-        if (!this.$x || !this.$x.$timezone) {
-            return oldStartOf.call(this, units, startOf);
-        }
-
-        let withoutTz = d(this.format("YYYY-MM-DD HH:mm:ss:SSS"));
-        let startOfWithoutTz = oldStartOf.call(withoutTz, units, startOf);
-        return startOfWithoutTz.tz(this.$x.$timezone, true);
-    };
-
-    d.tz = function (input, arg1, arg2) {
-        let parseFormat = arg2 && arg1;
-        let timezone = arg2 || arg1 || defaultTimezone;
-        let previousOffset = tzOffset(+d(), timezone);
-
-        if (typeof input !== "string") {
-            // timestamp number || js Date || Day.js
-            return d(input).tz(timezone);
-        }
-
-        let localTs = d.utc(input, parseFormat).valueOf();
-
-        let _fixOffset = fixOffset(localTs, previousOffset, timezone);
-        let targetTs = _fixOffset[0];
-        let targetOffset = _fixOffset[1];
-
-        let ins = d(targetTs).utcOffset(targetOffset);
-        ins.$x.$timezone = timezone;
-        return ins;
-    };
-
-    d.tz.guess = function () {
-        return Intl.DateTimeFormat().resolvedOptions().timeZone;
-    };
-
-    d.tz.setDefault = function (timezone) {
-        defaultTimezone = timezone;
-    };
-});
diff --git a/src/util-frontend.js b/src/util-frontend.ts
similarity index 59%
rename from src/util-frontend.js
rename to src/util-frontend.ts
index 2ea45af27..ff8d3db6d 100644
--- a/src/util-frontend.js
+++ b/src/util-frontend.ts
@@ -1,17 +1,43 @@
 import dayjs from "dayjs";
+import type { Dayjs } from "dayjs";
+import relativeTime from "dayjs/plugin/relativeTime";
+import timezone from "dayjs/plugin/timezone";
+import utc from "dayjs/plugin/utc";
 import { getTimeZones } from "@vvo/tzdb";
 import { localeDirection, currentLocale } from "./i18n";
 import { POSITION } from "vue-toastification";
 import { baseURL } from "./auth-client";
 
+interface TimezoneOption {
+    name: string;
+    value: string;
+    time: number;
+}
+
+interface ToastPluginOptions {
+    position: string;
+    containerClassName: string;
+    showCloseButtonOnHover: boolean;
+    filterBeforeCreate: (toast: { timeout?: number }, toasts: unknown[]) => unknown;
+}
+
+/**
+ * Extend dayjs with the plugins the frontend uses
+ * @returns The shared dayjs instance
+ */
+export function initDayjs(): Dayjs {
+    dayjs.extend(utc);
+    dayjs.extend(timezone);
+    dayjs.extend(relativeTime);
+    return dayjs;
+}
+
 /**
  * Returns the offset from UTC in hours for the current locale.
- * @param {string} timeZone Timezone to get offset for
- * @returns {number} The offset from UTC in hours.
- *
- * Generated by Trelent
+ * @param timeZone Timezone to get offset for
+ * @returns The offset from UTC in hours.
  */
-function getTimezoneOffset(timeZone) {
+function getTimezoneOffset(timeZone: string): number {
     const now = new Date();
     const tzString = now.toLocaleString("en-US", {
         timeZone,
@@ -24,24 +50,22 @@ function getTimezoneOffset(timeZone) {
 
 /**
  * Returns a list of timezones sorted by their offset from UTC.
- * @returns {object[]} A list of the given timezones sorted by their offset from UTC.
- *
- * Generated by Trelent
+ * @returns A list of the given timezones sorted by their offset from UTC.
  */
-export function timezoneList() {
-    let result = [];
+export function timezoneList(): TimezoneOption[] {
+    const result: TimezoneOption[] = [];
     const timeZones = getTimeZones();
 
-    for (let timezone of timeZones) {
+    for (const timezone of timeZones) {
         try {
-            let display = dayjs().tz(timezone.name).format("Z");
+            const display = dayjs().tz(timezone.name).format("Z");
 
             result.push({
                 name: `(UTC${display}) ${timezone.name}`,
                 value: timezone.name,
                 time: getTimezoneOffset(timezone.name),
             });
-        } catch (e) {
+        } catch {
             // Skipping not supported timezone.name by dayjs
         }
     }
@@ -63,9 +87,9 @@ export function timezoneList() {
 
 /**
  * Set the locale of the HTML page
- * @returns {void}
+ * @returns No return value.
  */
-export function setPageLocale() {
+export function setPageLocale(): void {
     const html = document.documentElement;
     html.setAttribute("lang", currentLocale());
     html.setAttribute("dir", localeDirection());
@@ -74,19 +98,19 @@ export function setPageLocale() {
 /**
  * Get the base URL
  * Mainly used for dev, because the backend and the frontend are in different ports.
- * @returns {string} Base URL
+ * @returns Base URL
  */
-export function getResBaseURL() {
+export function getResBaseURL(): string {
     return baseURL;
 }
 
 /**
  * Get the tag color options
  * Shared between components
- * @param {any} self Component
- * @returns {object[]} Colour options
+ * @param self Component
+ * @returns Colour options
  */
-export function colorOptions(self) {
+export function colorOptions(self: any): { name: string; color: string }[] {
     return [
         { name: self.$t("Gray"), color: "#4B5563" },
         { name: self.$t("Red"), color: "#DC2626" },
@@ -101,9 +125,9 @@ export function colorOptions(self) {
 
 /**
  * Loads the toast timeout settings from storage.
- * @returns {object} The toast plugin options object.
+ * @returns The toast plugin options object.
  */
-export function loadToastSettings() {
+export function loadToastSettings(): ToastPluginOptions {
     return {
         position: POSITION.BOTTOM_RIGHT,
         containerClassName: "toast-container mb-5",
@@ -121,13 +145,14 @@ export function loadToastSettings() {
 
 /**
  * Get timeout for success toasts
- * @returns {(number|boolean)} Timeout in ms. If false timeout disabled.
+ * @returns Timeout in ms. If false timeout disabled.
  */
-export function getToastSuccessTimeout() {
-    let successTimeout = 20000;
+export function getToastSuccessTimeout(): number | false {
+    let successTimeout: number | false = 20000;
+    const storedTimeout = (localStorage as any).toastSuccessTimeout;
 
-    if (localStorage.toastSuccessTimeout !== undefined) {
-        const parsedTimeout = parseInt(localStorage.toastSuccessTimeout);
+    if (storedTimeout !== undefined) {
+        const parsedTimeout = parseInt(storedTimeout);
         if (parsedTimeout != null && !Number.isNaN(parsedTimeout)) {
             successTimeout = parsedTimeout;
         }
@@ -142,13 +167,14 @@ export function getToastSuccessTimeout() {
 
 /**
  * Get timeout for error toasts
- * @returns {(number|boolean)} Timeout in ms. If false timeout disabled.
+ * @returns Timeout in ms. If false timeout disabled.
  */
-export function getToastErrorTimeout() {
-    let errorTimeout = -1;
+export function getToastErrorTimeout(): number | false {
+    let errorTimeout: number | false = -1;
+    const storedTimeout = (localStorage as any).toastErrorTimeout;
 
-    if (localStorage.toastErrorTimeout !== undefined) {
-        const parsedTimeout = parseInt(localStorage.toastErrorTimeout);
+    if (storedTimeout !== undefined) {
+        const parsedTimeout = parseInt(storedTimeout);
         if (parsedTimeout != null && !Number.isNaN(parsedTimeout)) {
             errorTimeout = parsedTimeout;
         }
@@ -162,14 +188,22 @@ export function getToastErrorTimeout() {
 }
 
 class TimeDurationFormatter {
+    private durationFormatOptions: { style: string };
+    private relativeTimeFormatOptions: { numeric: string };
+    private durationFormatInstance?: { format: (duration: object) => string };
+    private relativeTimeFormatInstance?: Intl.RelativeTimeFormat;
+
     /**
      * Default locale and options for Time Duration Formatter (supports both DurationFormat and RelativeTimeFormat)
      */
     constructor() {
         this.durationFormatOptions = { style: "long" };
         this.relativeTimeFormatOptions = { numeric: "always" };
-        if (Intl.DurationFormat !== undefined) {
-            this.durationFormatInstance = new Intl.DurationFormat(currentLocale(), this.durationFormatOptions);
+
+        const DurationFormat = (Intl as any).DurationFormat;
+
+        if (DurationFormat !== undefined) {
+            this.durationFormatInstance = new DurationFormat(currentLocale(), this.durationFormatOptions);
         } else {
             this.relativeTimeFormatInstance = new Intl.RelativeTimeFormat(
                 currentLocale(),
@@ -180,12 +214,14 @@ class TimeDurationFormatter {
 
     /**
      * Method to update the instance locale and options
-     * @param {string} locale Localization identifier (e.g., "en", "ar-sy") to update the instance with.
-     * @returns {void} No return value.
+     * @param locale Localization identifier (e.g., "en", "ar-sy") to update the instance with.
+     * @returns No return value.
      */
-    updateLocale(locale) {
-        if (Intl.DurationFormat !== undefined) {
-            this.durationFormatInstance = new Intl.DurationFormat(locale, this.durationFormatOptions);
+    updateLocale(locale: string): void {
+        const DurationFormat = (Intl as any).DurationFormat;
+
+        if (DurationFormat !== undefined) {
+            this.durationFormatInstance = new DurationFormat(locale, this.durationFormatOptions);
         } else {
             this.relativeTimeFormatInstance = new Intl.RelativeTimeFormat(locale, this.relativeTimeFormatOptions);
         }
@@ -193,10 +229,10 @@ class TimeDurationFormatter {
 
     /**
      * Method to convert seconds into Human readable format
-     * @param {number} seconds Receive value in seconds.
-     * @returns {string} String converted to Days Mins Seconds Format
+     * @param seconds Receive value in seconds.
+     * @returns String converted to Days Mins Seconds Format
      */
-    secondsToHumanReadableFormat(seconds) {
+    secondsToHumanReadableFormat(seconds: number): string {
         const days = Math.floor(seconds / 86400);
         const hours = Math.floor((seconds % 86400) / 3600);
         const minutes = Math.floor(((seconds % 86400) % 3600) / 60);
@@ -212,18 +248,18 @@ class TimeDurationFormatter {
             });
         }
 
-        const parts = [];
+        const parts: string[] = [];
         /**
          * Build the formatted string from parts
          * 1. Get the relative time formatted parts from the instance.
          * 2. Filter out the relevant parts literal (unit of time) or integer (value).
          * 3. Map out the required values.
-         * @param {number} value Receives value in seconds.
-         * @param {string} unitOfTime Expected unit of time after conversion.
-         * @returns {void}
+         * @param value Receives value in seconds.
+         * @param unitOfTime Expected unit of time after conversion.
+         * @returns No return value.
          */
-        const toFormattedPart = (value, unitOfTime) => {
-            const partsArray = this.relativeTimeFormatInstance.formatToParts(value, unitOfTime);
+        const toFormattedPart = (value: number, unitOfTime: Intl.RelativeTimeFormatUnit) => {
+            const partsArray = this.relativeTimeFormatInstance!.formatToParts(value, unitOfTime);
             const filteredParts = partsArray
                 .filter((part, index) => part.type === "integer" || (part.type === "literal" && index > 0))
                 .map((part) => part.value);
@@ -248,7 +284,7 @@ class TimeDurationFormatter {
         if (parts.length > 0) {
             return `${parts.join(" ")}`;
         }
-        return this.relativeTimeFormatInstance.format(0, "second"); // Handle case for 0 seconds
+        return this.relativeTimeFormatInstance!.format(0, "second"); // Handle case for 0 seconds
     }
 }
 
diff --git a/src/util.ts b/src/util.ts
index a1f66884e..fb71f9188 100644
--- a/src/util.ts
+++ b/src/util.ts
@@ -3,14 +3,7 @@
 // Common Util for frontend and backend
 */
 
-import dayjsFrontend from "dayjs";
-
-// For dayjs plugins' type checking, don't remove event though it is not used in this file
-// eslint-disable-next-line @typescript-eslint/no-unused-vars
-import * as timezone from "dayjs/plugin/timezone";
-// eslint-disable-next-line @typescript-eslint/no-unused-vars
-import * as utc from "dayjs/plugin/utc";
-
+import dayjs from "dayjs";
 import jsonata from "jsonata";
 
 /**
@@ -23,12 +16,6 @@ export function isDevEnv() {
 
 export const isNode = typeof process !== "undefined" && process?.versions?.node;
 
-/**
- * Smarter dayjs import that supports both frontend and backend
- * @returns {dayjs.Dayjs} dayjs instance
- */
-const dayjs = isNode ? require("dayjs") : dayjsFrontend;
-
 export const devOriginList = [
     "http://127.0.0.1:3000",
     "http://127.0.0.1:3001",
diff --git a/test/backend-test/monitors/test-kafka-producer.js b/test/backend-test/monitors/test-kafka-producer.js
index ec8dd5022..c6e7a63f5 100644
--- a/test/backend-test/monitors/test-kafka-producer.js
+++ b/test/backend-test/monitors/test-kafka-producer.js
@@ -1,6 +1,6 @@
 const { describe, test } = require("node:test");
 const assert = require("node:assert");
-const { kafkaProducerAsync } = require("../../../server/util-server");
+const { kafkaProducerAsync } = require("../../../server/util");
 
 describe("Kafka Producer", () => {
     test("rejects when broker is not reachable", async () => {
diff --git a/test/backend-test/test-cert-hostname-match.js b/test/backend-test/test-cert-hostname-match.js
index f35b7aa76..b430ba5d4 100644
--- a/test/backend-test/test-cert-hostname-match.js
+++ b/test/backend-test/test-cert-hostname-match.js
@@ -2,7 +2,7 @@ const { describe, test } = require("node:test");
 
 const assert = require("node:assert");
 
-const { checkCertificateHostname } = require("../../server/util-server");
+const { checkCertificateHostname } = require("../../server/util");
 
 const testCert = `
 -----BEGIN CERTIFICATE-----
diff --git a/test/backend-test/test-domain.js b/test/backend-test/test-domain.js
index d48f5ee48..678f8d593 100644
--- a/test/backend-test/test-domain.js
+++ b/test/backend-test/test-domain.js
@@ -8,10 +8,9 @@ const TestDB = require("../mock-testdb");
 const { R } = require("redbean-node");
 const { Notification } = require("../../server/notification");
 const { Settings } = require("../../server/settings");
-const { setSetting } = require("../../server/util-server");
+const { setSetting } = require("../../server/util");
 const dayjs = require("dayjs");
 const { retryExternalService } = require("./test-util");
-dayjs.extend(require("dayjs/plugin/utc"));
 
 const testDb = new TestDB("./data/test-domain");
 
diff --git a/test/backend-test/test-globalping.js b/test/backend-test/test-globalping.js
index a02cbbceb..d7ea21643 100644
--- a/test/backend-test/test-globalping.js
+++ b/test/backend-test/test-globalping.js
@@ -1,6 +1,6 @@
 const { describe, test, mock } = require("node:test");
 const assert = require("node:assert");
-const { encodeBase64 } = require("../../server/util-server");
+const { encodeBase64 } = require("../../server/util");
 const { UP, PENDING } = require("../../src/util");
 
 describe("GlobalpingMonitorType", () => {
diff --git a/test/backend-test/test-maintenance.ts b/test/backend-test/test-maintenance.ts
index 2812a87a9..75a646541 100644
--- a/test/backend-test/test-maintenance.ts
+++ b/test/backend-test/test-maintenance.ts
@@ -4,9 +4,6 @@ import { createRequire } from "node:module";
 import dayjs from "dayjs";
 
 const require = createRequire(import.meta.url);
-dayjs.extend(require("dayjs/plugin/utc"));
-dayjs.extend(require("dayjs/plugin/customParseFormat"));
-dayjs.extend(require("../../server/modules/dayjs/plugin/timezone"));
 
 const Maintenance = require("../../server/model/maintenance");
 
diff --git a/test/backend-test/test-radius.js b/test/backend-test/test-radius.js
index 9d8eb8531..cccf55368 100644
--- a/test/backend-test/test-radius.js
+++ b/test/backend-test/test-radius.js
@@ -2,7 +2,7 @@ const { describe, test } = require("node:test");
 const assert = require("node:assert/strict");
 const dgram = require("dgram");
 const radius = require("radius");
-const { radius: radiusCheck } = require("../../server/util-server");
+const { radius: radiusCheck } = require("../../server/util");
 
 /**
  * Start a UDP RADIUS server that replies to every Access-Request with the given response code.
diff --git a/test/backend-test/test-status-page.js b/test/backend-test/test-status-page.js
index 3a3060562..2e2834d7f 100644
--- a/test/backend-test/test-status-page.js
+++ b/test/backend-test/test-status-page.js
@@ -1,8 +1,6 @@
 const { describe, test, mock } = require("node:test");
 const assert = require("node:assert");
 const StatusPage = require("../../server/model/status_page");
-const dayjs = require("dayjs");
-const utc = require("dayjs/plugin/utc");
 const {
     STATUS_PAGE_ALL_UP,
     STATUS_PAGE_ALL_DOWN,
@@ -10,8 +8,6 @@ const {
     STATUS_PAGE_MAINTENANCE,
 } = require("../../src/util");
 
-dayjs.extend(utc);
-
 describe("StatusPage", () => {
     describe("getStatusDescription()", () => {
         test("returns 'No Services' when status is -1", () => {
diff --git a/test/backend-test/test-uptime-calculator-storage.ts b/test/backend-test/test-uptime-calculator-storage.ts
index ae14a56e5..71c70e60f 100644
--- a/test/backend-test/test-uptime-calculator-storage.ts
+++ b/test/backend-test/test-uptime-calculator-storage.ts
@@ -7,7 +7,6 @@ const { UptimeCalculator } = require("../../server/uptime-calculator");
 const { R } = require("redbean-node");
 const dayjs = require("dayjs");
 const { UP } = require("../../src/util");
-dayjs.extend(require("dayjs/plugin/utc"));
 
 const originals = {
     getAll: R.getAll,
diff --git a/test/backend-test/test-uptime-calculator.js b/test/backend-test/test-uptime-calculator.js
index d3508f159..6f48c39a1 100644
--- a/test/backend-test/test-uptime-calculator.js
+++ b/test/backend-test/test-uptime-calculator.js
@@ -2,10 +2,8 @@ const { describe, test } = require("node:test");
 const assert = require("node:assert");
 const { UptimeCalculator } = require("../../server/uptime-calculator");
 const dayjs = require("dayjs");
+
 const { UP, DOWN, PENDING, MAINTENANCE } = require("../../src/util");
-dayjs.extend(require("dayjs/plugin/utc"));
-dayjs.extend(require("../../server/modules/dayjs/plugin/timezone"));
-dayjs.extend(require("dayjs/plugin/customParseFormat"));
 
 /**
  * Create a calculator whose bucket loading is stubbed, so update() does not query the database
diff --git a/test/backend-test/test-util.js b/test/backend-test/test-util.js
index 7e0b17c60..28b54b39c 100644
--- a/test/backend-test/test-util.js
+++ b/test/backend-test/test-util.js
@@ -33,9 +33,6 @@ async function retryExternalService(testFn, maxAttempts = 5) {
 
 module.exports = { retryExternalService };
 
-dayjs.extend(require("dayjs/plugin/utc"));
-dayjs.extend(require("dayjs/plugin/customParseFormat"));
-
 describe("Server Utilities", () => {
     test("SQL_DATETIME_FORMAT constant matches MariaDB/MySQL format", () => {
         assert.strictEqual(SQL_DATETIME_FORMAT, "YYYY-MM-DD HH:mm:ss");
diff --git a/test/setup.ts b/test/setup.ts
new file mode 100644
index 000000000..4426119df
--- /dev/null
+++ b/test/setup.ts
@@ -0,0 +1,3 @@
+import { initDayjs } from "../server/util";
+
+initDayjs();