diff --git a/locales/index.js b/locales/index.js
index a88b0c67ad..7801f1275b 100644
--- a/locales/index.js
+++ b/locales/index.js
@@ -51,7 +51,7 @@ const primaries = {
 // 何故か文字列にバックスペース文字が混入することがあり、YAMLが壊れるので取り除く
 const clean = (text) => text.replace(new RegExp(String.fromCodePoint(0x08), 'g'), '');
 
-const locales = languages.reduce((a, c) => (a[c] = yaml.load(clean(fs.readFileSync(`${__dirname}/${c}.yml`, 'utf-8'))) || {}, a), {});
+const locales = languages.reduce((a, c) => (a[c] = yaml.load(clean(fs.readFileSync(new URL(`${c}.yml`, import.meta.url), 'utf-8'))) || {}, a), {});
 
 export default Object.entries(locales)
 	.reduce((a, [k ,v]) => (a[k] = (() => {
diff --git a/packages/sw/build.js b/packages/sw/build.js
index ad16fb9497..5efab5713d 100644
--- a/packages/sw/build.js
+++ b/packages/sw/build.js
@@ -1,10 +1,13 @@
 // @ts-check
 
-const esbuild = require('esbuild');
-const locales = require('../../locales');
-const meta = require('../../package.json');
+import * as esbuild from 'esbuild';
+import locales from '../../locales/index.js';
+import meta from '../../package.json' assert { type: "json" };
+import { fileURLToPath } from 'node:url';
 const watch = process.argv[2]?.includes('watch');
 
+const __dirname = fileURLToPath(new URL(".", import.meta.url))
+
 console.log('Starting SW building...');
 
 /** @type {esbuild.BuildOptions} */
diff --git a/packages/sw/package.json b/packages/sw/package.json
index a2bead3dd4..a60f8230c2 100644
--- a/packages/sw/package.json
+++ b/packages/sw/package.json
@@ -19,5 +19,6 @@
 		"eslint": "8.44.0",
 		"eslint-plugin-import": "2.27.5",
 		"typescript": "5.1.6"
-	}
+	},
+	"type": "module"
 }