diff --git a/build/prepare.js b/build/prepare.js
index 5ba4e5bf..85246554 100644
--- a/build/prepare.js
+++ b/build/prepare.js
@@ -11,6 +11,7 @@ if (process.env.npm_execpath.includes('yarn')) {
 const dir = path.dirname(path.dirname(require.resolve('@types/node/package.json')));
 const types = fs.readdirSync(dir).filter((i) => !['sharedworker', 'serviceworker'].includes(i));
 
+/** @type {import('typescript/lib/typescript').CompilerOptions} */
 const compilerOptionsBase = {
     target: 'es2020',
     module: 'commonjs',
@@ -20,6 +21,7 @@ const compilerOptionsBase = {
     sourceMap: false,
     composite: true,
     strictBindCallApply: true,
+    resolveJsonModule: true,
     experimentalDecorators: true,
     // emitDecoratorMetadata: true,
     incremental: true,
@@ -53,7 +55,7 @@ const configFlat = (name) => ({
         rootDir: '.',
     },
     include: ['**/*.ts'],
-    exclude: ['public'],
+    exclude: ['public', 'frontend'],
 });
 
 for (const name of ['plugins', 'modules']) {
@@ -73,7 +75,10 @@ const UIConfig = {
     exclude: [
         'packages/ui-default/public',
     ],
-    include: ['ts', 'tsx'].flatMap((ext) => [].map((name) => `${name}/**/public/**/*.${ext}`).concat(`packages/ui-default/**/*.${ext}`)),
+    include: ['ts', 'tsx']
+        .flatMap((ext) => ['plugins', 'modules']
+            .flatMap((name) => [`${name}/**/public/**/*.${ext}`, `${name}/**/frontend/**/*.${ext}`])
+            .concat(`packages/ui-default/**/*.${ext}`)),
     compilerOptions: {
         experimentalDecorators: true,
         esModuleInterop: true,
diff --git a/packages/onlyoffice/frontend/office.page.ts b/packages/onlyoffice/frontend/office.page.ts
index 602c812c..c45a1c27 100644
--- a/packages/onlyoffice/frontend/office.page.ts
+++ b/packages/onlyoffice/frontend/office.page.ts
@@ -1,5 +1,7 @@
 import { $, addPage, AutoloadPage } from '@hydrooj/ui-default';
 
+/* global DocsAPI */
+
 let loaded = false;
 async function load() {
   if (loaded) return Promise.resolve();
@@ -21,7 +23,7 @@ const loader = (mode) => async (element) => {
   const t = new URL(url, window.location.href).pathname.split('.');
   const n = new URL(url, window.location.href).pathname.split('/');
   const lang = UserContext.viewLang.includes('_') ? UserContext.viewLang.split('_')[0] : UserContext.viewLang;
-  // eslint-disable-next-line no-undef
+  // @ts-ignore
   window.editor = new DocsAPI.DocEditor(id, {
     document: {
       fileType: t[t.length - 1],
diff --git a/packages/prom-client/index.ts b/packages/prom-client/index.ts
index 15c5aacf..29c55a45 100644
--- a/packages/prom-client/index.ts
+++ b/packages/prom-client/index.ts
@@ -1,5 +1,5 @@
 import { hostname } from 'os';
-import { AggregatorRegistry, metric } from 'prom-client';
+import { AggregatorRegistry, Metric } from 'prom-client';
 import { Context, Handler, SystemModel } from 'hydrooj';
 import { createRegistry } from './metrics';
 
@@ -14,7 +14,7 @@ declare module 'hydrooj' {
     }
 }
 
-const instances: Record<string, metric[]> = {};
+const instances: Record<string, Metric[]> = {};
 
 class MetricsHandler extends Handler {
     noCheckPermView = true;