diff --git a/packages/runtime/package.json b/packages/runtime/package.json
index 6d721979..95b3bd52 100644
--- a/packages/runtime/package.json
+++ b/packages/runtime/package.json
@@ -10,6 +10,7 @@
     "@emotion/styled": "^11",
     "@meta-ui/core": "^0.1.0",
     "@sinclair/typebox": "^0.19.2",
+    "dayjs": "^1.10.6",
     "framer-motion": "^4",
     "lodash": "^4.17.21",
     "mitt": "^3.0.0",
diff --git a/packages/runtime/src/store.ts b/packages/runtime/src/store.ts
index be8bd431..ce94a98b 100644
--- a/packages/runtime/src/store.ts
+++ b/packages/runtime/src/store.ts
@@ -1,7 +1,11 @@
-import { useMemo, useState } from "react";
+import { useState } from "react";
 import create from "zustand";
 import _ from "lodash";
 import mitt from "mitt";
+import dayjs from "dayjs";
+import relativeTime from "dayjs/plugin/relativeTime";
+
+dayjs.extend(relativeTime);
 
 export const useStore = create<Record<string, any>>(() => ({}));
 
@@ -31,6 +35,9 @@ export function parseExpression(raw: string): {
 }
 
 // TODO: use web worker
+const builtIn = {
+  dayjs,
+};
 export function evalInContext(raw: string, ctx: Record<string, any>) {
   try {
     const { dynamic, expression } = parseExpression(raw);
@@ -42,6 +49,10 @@ export function evalInContext(raw: string, ctx: Record<string, any>) {
         return expression;
       }
     }
+    Object.keys(builtIn).forEach((key) => {
+      // @ts-ignore
+      self[key] = builtIn[key];
+    });
     Object.keys(ctx).forEach((key) => {
       // @ts-ignore
       self[key] = ctx[key];
@@ -51,6 +62,10 @@ export function evalInContext(raw: string, ctx: Record<string, any>) {
     // console.error(error);
     return undefined;
   } finally {
+    Object.keys(builtIn).forEach((key) => {
+      // @ts-ignore
+      delete self[key];
+    });
     Object.keys(ctx).forEach((key) => {
       // @ts-ignore
       delete self[key];
@@ -77,8 +92,7 @@ export function useExpression(raw: string) {
 export const emitter = mitt<Record<string, any>>();
 
 // EXPERIMENT: utils
-emitter.on("$utils", ({ name, parameters, ...rest }) => {
-  console.log(name, parameters, rest);
+emitter.on("$utils", ({ name, parameters }) => {
   if (name === "alert") {
     window.alert(parameters);
   }
diff --git a/yarn.lock b/yarn.lock
index 2d9b2834..c09cfbb3 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3290,6 +3290,11 @@ dateformat@^3.0.0:
   resolved "http://192.168.26.29:7001/dateformat/download/dateformat-3.0.3.tgz#a6e37499a4d9a9cf85ef5872044d62901c9889ae"
   integrity sha1-puN0maTZqc+F71hyBE1ikByYia4=
 
+dayjs@^1.10.6:
+  version "1.10.6"
+  resolved "http://192.168.26.29:7001/dayjs/download/dayjs-1.10.6.tgz#288b2aa82f2d8418a6c9d4df5898c0737ad02a63"
+  integrity sha1-KIsqqC8thBimydTfWJjAc3rQKmM=
+
 debug@4, debug@^4.0.0, debug@^4.0.1, debug@^4.1.0, debug@^4.1.1, debug@^4.3.1:
   version "4.3.2"
   resolved "http://192.168.26.29:7001/debug/download/debug-4.3.2.tgz#f0a49c18ac8779e31d4a0c6029dfb76873c7428b"