update dependencies

.npmignore

@@ -1,3 +1,3 @@
 .editorconfig
-.eslintrc
+eslint.config.mjs
 .prettierrc

eslint.config.mjs

@@ -0,0 +1,43 @@
+import globals from 'globals';
+import path from 'node:path';
+import { fileURLToPath } from 'node:url';
+import js from '@eslint/js';
+import { FlatCompat } from '@eslint/eslintrc';
+
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = path.dirname(__filename);
+const compat = new FlatCompat({
+  baseDirectory: __dirname,
+  recommendedConfig: js.configs.recommended,
+  allConfig: js.configs.all,
+});
+
+export default [
+  ...compat.extends('plugin:prettier/recommended', 'eslint:recommended'),
+  {
+    languageOptions: {
+      globals: {
+        ...globals.node,
+      },
+
+      ecmaVersion: 2020,
+      sourceType: 'module',
+    },
+
+    rules: {
+      'no-var': 'error',
+      'prefer-const': 'error',
+      'no-use-before-define': 'error',
+      'no-mixed-spaces-and-tabs': 'error',
+      'no-nested-ternary': 'error',
+      'no-unused-vars': 'error',
+
+      'prettier/prettier': [
+        'error',
+        {
+          endOfLine: 'auto',
+        },
+      ],
+    },
+  },
+];