diff --git a/Build/build-cdn-conf.ts b/Build/build-cdn-conf.ts
index 8d9e531b..b0c62c7b 100644
--- a/Build/build-cdn-conf.ts
+++ b/Build/build-cdn-conf.ts
@@ -13,7 +13,7 @@ const getS3OSSDomains = async (): Promise<Set<string>> => {
   const publicSuffixFile = Bun.file(publicSuffixPath);
 
   if (await publicSuffixFile.exists()) {
-    for await (const line of readFileByLine(publicSuffixPath)) {
+    for await (const line of readFileByLine(publicSuffixFile)) {
       trie.add(line);
     }
   } else {
diff --git a/Build/download-previous-build.js b/Build/download-previous-build.ts
similarity index 72%
rename from Build/download-previous-build.js
rename to Build/download-previous-build.ts
index 87615bbf..5e7fd770 100644
--- a/Build/download-previous-build.js
+++ b/Build/download-previous-build.ts
@@ -1,15 +1,14 @@
-// @ts-check
-const tar = require('tar');
-const fsp = require('fs/promises');
-const path = require('path');
-const { tmpdir } = require('os');
-const { Readable } = require('stream');
-const { pipeline } = require('stream/promises');
-const { readFileByLine } = require('./lib/fetch-remote-text-by-line');
-const { isCI } = require('ci-info');
-const { task, traceAsync } = require('./lib/trace-runner');
+import tar from 'tar';
+import fsp from 'fs/promises';
+import path from 'path';
+import os from 'os';
+import { Readable } from 'stream';
+import { pipeline } from 'stream/promises';
+import { readFileByLine } from './lib/fetch-remote-text-by-line';
+import { isCI } from 'ci-info';
+import { task, traceAsync } from './lib/trace-runner';
 
-const downloadPreviousBuild = task(__filename, async () => {
+export const downloadPreviousBuild = task(__filename, async () => {
   const filesList = ['Clash', 'List'];
 
   let allFileExists = true;
@@ -41,7 +40,7 @@ const downloadPreviousBuild = task(__filename, async () => {
     return;
   }
 
-  const extractedPath = path.join(tmpdir(), `sukka-surge-last-build-extracted-${Date.now()}`);
+  const extractedPath = path.join(os.tmpdir(), `sukka-surge-last-build-extracted-${Date.now()}`);
 
   await traceAsync(
     'Download and extract previous build',
@@ -49,7 +48,7 @@ const downloadPreviousBuild = task(__filename, async () => {
       fetch('https://codeload.github.com/sukkalab/ruleset.skk.moe/tar.gz/master'),
       fsp.mkdir(extractedPath, { recursive: true })
     ]).then(([resp]) => pipeline(
-      Readable.fromWeb(resp.body),
+      Readable.fromWeb(resp.body!),
       tar.x({
         cwd: extractedPath,
         /**
@@ -78,7 +77,7 @@ const downloadPreviousBuild = task(__filename, async () => {
   // return fsp.unlink(extractedPath).catch(() => { });
 });
 
-const downloadPublicSuffixList = task(__filename, async () => {
+export const downloadPublicSuffixList = task(__filename, async () => {
   const publicSuffixDir = path.resolve(__dirname, '../node_modules/.cache');
   const publicSuffixPath = path.join(publicSuffixDir, 'public_suffix_list_dat.txt');
 
@@ -90,9 +89,6 @@ const downloadPublicSuffixList = task(__filename, async () => {
   return Bun.write(publicSuffixPath, resp);
 }, 'download-publicsuffixlist');
 
-module.exports.downloadPreviousBuild = downloadPreviousBuild;
-module.exports.downloadPublicSuffixList = downloadPublicSuffixList;
-
 if (import.meta.main) {
   Promise.all([
     downloadPreviousBuild(),
diff --git a/Build/lib/create-file.js b/Build/lib/create-file.js
index 7126309d..ffc0e53e 100644
--- a/Build/lib/create-file.js
+++ b/Build/lib/create-file.js
@@ -19,7 +19,7 @@ async function compareAndWriteFile(linesA, filePath) {
   } else {
     let index = 0;
 
-    for await (const lineB of readFileByLine(filePath)) {
+    for await (const lineB of readFileByLine(file)) {
       const lineA = linesA[index];
       index++;
 
diff --git a/bun.lockb b/bun.lockb
index 810feff1..7ea8d990 100755
Binary files a/bun.lockb and b/bun.lockb differ
diff --git a/package.json b/package.json
index 44ac7c0b..35ea0886 100644
--- a/package.json
+++ b/package.json
@@ -34,6 +34,7 @@
   "devDependencies": {
     "@eslint-sukka/node": "^4.1.7",
     "@types/mocha": "10.0.2",
+    "@types/tar": "^6.1.9",
     "bun-types": "^1.0.11",
     "chai": "4.3.10",
     "eslint-config-sukka": "4.1.7",