diff --git a/e2e-test/flat-config/__snapshots__/index.test.ts.snap b/e2e-test/flat-config/__snapshots__/index.test.ts.snap
new file mode 100644
index 00000000..fed83f40
--- /dev/null
+++ b/e2e-test/flat-config/__snapshots__/index.test.ts.snap
@@ -0,0 +1,3 @@
+// Vitest Snapshot v1, https://vitest.dev/guide/snapshot.html
+
+exports[`fix problems with flat config 1`] = `"const a = 1;"`;
diff --git a/e2e-test/flat-config/index.test.ts b/e2e-test/flat-config/index.test.ts
new file mode 100644
index 00000000..c6450568
--- /dev/null
+++ b/e2e-test/flat-config/index.test.ts
@@ -0,0 +1,60 @@
+import { afterEach, test, expect } from 'vitest';
+import { createIFF } from '../../src/test-util/fixtures.js';
+import dedent from 'dedent';
+import { ChildProcessWithoutNullStreams, spawn } from 'child_process';
+import { createStreamWatcher } from '../../src/test-util/stream-watcher.js';
+import { readFile } from 'node:fs/promises';
+import { dirname, join } from 'path';
+import { fileURLToPath } from 'url';
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
+
+const ETX = String.fromCharCode(0x03); // ^C
+const LF = String.fromCharCode(0x0a); // \n
+
+const iff = await createIFF({
+  'src/index.js': 'let a = 1;',
+  'eslint.config.js': dedent`
+    export default [
+      { rules: { 'prefer-const': 'error' } },
+    ];
+  `,
+  'package.json': '{ "type": "module" }',
+});
+
+function waitForClose(child: ChildProcessWithoutNullStreams) {
+  return new Promise<void>((resolve) => {
+    child.on('close', resolve);
+  });
+}
+
+let child: ChildProcessWithoutNullStreams;
+afterEach(async () => {
+  child.kill();
+  await waitForClose(child);
+  await iff.reset();
+});
+
+test('fix problems with flat config', async () => {
+  child = spawn(
+    'node',
+    [
+      join(__dirname, '../../bin/eslint-interactive.js'),
+      'src',
+      // merge stderr to stdout
+      '2>&1',
+    ],
+    { shell: true, stdio: 'pipe', cwd: iff.rootDir, env: { ...process.env, ESLINT_USE_FLAT_CONFIG: 'true' } },
+  );
+  const streamWatcher = createStreamWatcher(child.stdout, { debug: false });
+
+  await streamWatcher.match(/Which rules would you like to apply action\?/);
+  child.stdin.write(' '); // Select `prefer-const` rule
+  child.stdin.write(LF); // Confirm the choice
+  await streamWatcher.match(/Which action do you want to do\?/);
+  child.stdin.write('1'); // Focus on `Run `eslint --fix``
+  child.stdin.write(LF); // Confirm the choice
+  await streamWatcher.match(/Fixing done\./);
+  expect(await readFile(iff.paths['src/index.js'], 'utf-8')).toMatchSnapshot();
+  child.stdin.write(ETX); // Exit
+});
diff --git a/e2e-test/flat-config/package.json b/e2e-test/flat-config/package.json
new file mode 100644
index 00000000..1101ade6
--- /dev/null
+++ b/e2e-test/flat-config/package.json
@@ -0,0 +1,6 @@
+{
+  "type": "module",
+  "dependencies": {
+    "eslint-interactive": "../../"
+  }
+}
diff --git a/e2e-test/global-installation/index.test.ts b/e2e-test/global-installation/index.test.ts
index 0a9092f3..3ece619f 100644
--- a/e2e-test/global-installation/index.test.ts
+++ b/e2e-test/global-installation/index.test.ts
@@ -36,7 +36,7 @@ test('can print error with eslint-formatter-codeframe', async () => {
     ],
     { shell: true, stdio: 'pipe', cwd: __dirname, env: { ...process.env, ESLINT_USE_FLAT_CONFIG: 'false' } },
   );
-  const streamWatcher = createStreamWatcher(child.stdout, { debug: true });
+  const streamWatcher = createStreamWatcher(child.stdout, { debug: false });
 
   await streamWatcher.match(/Which rules would you like to apply action\?/);
   child.stdin.write(' '); // Select `semi` rule
diff --git a/fixtures/eslint.config.mjs b/fixtures/eslint.config.mjs
new file mode 100644
index 00000000..85151cbf
--- /dev/null
+++ b/fixtures/eslint.config.mjs
@@ -0,0 +1,40 @@
+// @ts-check
+
+import { FlatCompat } from '@eslint/eslintrc';
+
+const compat = new FlatCompat();
+
+export default [
+  ...compat.plugins('import'),
+  ...compat.env({ node: true, es2020: true }),
+  {
+    files: ['**/*.js', '**/*.mjs', '**/*.jsx'],
+    languageOptions: {
+      sourceType: 'module',
+      ecmaVersion: 2020,
+      parserOptions: {
+        ecmaFeatures: {
+          jsx: true,
+        },
+      },
+    },
+    rules: {
+      'semi': 2,
+      'import/order': [2, { alphabetize: { order: 'asc' } }],
+      'prefer-const': 2,
+      'no-unused-vars': [
+        2,
+        {
+          ignoreRestSiblings: true,
+          argsIgnorePattern: '^_',
+          caughtErrors: 'all',
+        },
+      ],
+      'ban-exponentiation-operator': 'off', // Disable in flat config
+      'no-useless-escape': 2,
+      'no-unsafe-negation': 2,
+      'arrow-body-style': [2, 'always'],
+
+    },
+  },
+]
diff --git a/package.json b/package.json
index 70caa62a..9bf6335b 100644
--- a/package.json
+++ b/package.json
@@ -44,7 +44,7 @@
     "@types/node": "^20.8.10",
     "@types/yargs": "^17.0.29",
     "dedent": "^1.5.1",
-    "eslint": "^8.53.0",
+    "eslint": "^8.57.0",
     "fs-extra": "^11.1.1",
     "import-meta-resolve": "^4.0.0",
     "npm-run-all": "^4.1.5",
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 6328f9bb..cbb0e158 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -55,7 +55,7 @@ importers:
     devDependencies:
       '@mizdra/eslint-config-mizdra':
         specifier: 2.1.0-alpha.0
-        version: 2.1.0-alpha.0(eslint@8.53.0)(prettier@3.0.3)(typescript@5.2.2)
+        version: 2.1.0-alpha.0(eslint@8.57.0)(prettier@3.0.3)(typescript@5.2.2)
       '@mizdra/inline-fixture-files':
         specifier: ^1.1.0
         version: 1.1.0
@@ -90,8 +90,8 @@ importers:
         specifier: ^1.5.1
         version: 1.5.1
       eslint:
-        specifier: ^8.53.0
-        version: 8.53.0
+        specifier: ^8.57.0
+        version: 8.57.0
       fs-extra:
         specifier: ^11.1.1
         version: 11.1.1
@@ -378,14 +378,14 @@ packages:
     dev: true
     optional: true
 
-  /@eslint-community/eslint-utils@4.4.0(eslint@8.53.0):
+  /@eslint-community/eslint-utils@4.4.0(eslint@8.57.0):
     resolution: {integrity: sha512-1/sA4dwrzBAyeUoQ6oxahHKmrZvsnLCg4RfxW3ZFGGmQkSNQPFNLV9CUEFQP1x9EYXHTo5p6xdhZM1Ne9p/AfA==}
     engines: {node: ^12.22.0 || ^14.17.0 || >=16.0.0}
     peerDependencies:
       eslint: ^6.0.0 || ^7.0.0 || >=8.0.0
     dependencies:
-      eslint: 8.53.0
-      eslint-visitor-keys: 3.4.1
+      eslint: 8.57.0
+      eslint-visitor-keys: 3.4.3
     dev: true
 
   /@eslint-community/regexpp@4.10.0:
@@ -393,8 +393,8 @@ packages:
     engines: {node: ^12.0.0 || ^14.0.0 || >=16.0.0}
     dev: true
 
-  /@eslint/eslintrc@2.1.3:
-    resolution: {integrity: sha512-yZzuIG+jnVu6hNSzFEN07e8BxF3uAzYtQb6uDkaYZLo6oYZDCq454c5kB8zxnzfCYyP4MIuyBn10L0DqwujTmA==}
+  /@eslint/eslintrc@2.1.4:
+    resolution: {integrity: sha512-269Z39MS6wVJtsoUl10L60WdkhJVdPG24Q4eZTH3nnF6lpvSShEK3wQjDX9JRWAUPvPh7COouPpU9IrqaZFvtQ==}
     engines: {node: ^12.22.0 || ^14.17.0 || >=16.0.0}
     dependencies:
       ajv: 6.12.6
@@ -410,8 +410,8 @@ packages:
       - supports-color
     dev: true
 
-  /@eslint/js@8.53.0:
-    resolution: {integrity: sha512-Kn7K8dx/5U6+cT1yEhpX1w4PCSg0M+XyRILPgvwcEBjerFWCwQj5sbr3/VmxqV0JGHCBCzyd6LxypEuehypY1w==}
+  /@eslint/js@8.57.0:
+    resolution: {integrity: sha512-Ys+3g2TaW7gADOJzPt83SJtCDhMjndcDMFVQ/Tj9iA1BfJzFKD9mAUXT3OenpuPHbI6P/myECxRJrofUsDx/5g==}
     engines: {node: ^12.22.0 || ^14.17.0 || >=16.0.0}
     dev: true
 
@@ -420,11 +420,11 @@ packages:
     engines: {node: '>=14'}
     dev: true
 
-  /@humanwhocodes/config-array@0.11.13:
-    resolution: {integrity: sha512-JSBDMiDKSzQVngfRjOdFXgFfklaXI4K9nLF49Auh21lmBWRLIK3+xTErTWD4KU54pb6coM6ESE7Awz/FNU3zgQ==}
+  /@humanwhocodes/config-array@0.11.14:
+    resolution: {integrity: sha512-3T8LkOmg45BV5FICb15QQMsyUSWrQ8AygVfC7ZG32zOalnqrilm018ZVCw0eapXux8FtA33q8PSRSstjee3jSg==}
     engines: {node: '>=10.10.0'}
     dependencies:
-      '@humanwhocodes/object-schema': 2.0.1
+      '@humanwhocodes/object-schema': 2.0.2
       debug: 4.3.4
       minimatch: 3.1.2
     transitivePeerDependencies:
@@ -436,8 +436,8 @@ packages:
     engines: {node: '>=12.22'}
     dev: true
 
-  /@humanwhocodes/object-schema@2.0.1:
-    resolution: {integrity: sha512-dvuCeX5fC9dXgJn9t+X5atfmgQAzUOWqS1254Gh0m6i8wKd10ebXkfNKiRK+1GWi/yTvvLDHpoxLr0xxxeslWw==}
+  /@humanwhocodes/object-schema@2.0.2:
+    resolution: {integrity: sha512-6EwiSjwWYP7pTckG6I5eyFANjPhmPjUX9JRLUSfNPC7FX7zK9gyZAfUEaECL6ALTpGX5AjnBq3C9XmVWPitNpw==}
     dev: true
 
   /@jest/schemas@29.6.3:
@@ -451,7 +451,7 @@ packages:
     resolution: {integrity: sha512-eF2rxCRulEKXHTRiDrDy6erMYWqNw4LPdQ8UQA4huuxaQsVeRPFl2oM8oDGxMFhJUWZf9McpLtJasDDZb/Bpeg==}
     dev: true
 
-  /@mizdra/eslint-config-mizdra@2.1.0-alpha.0(eslint@8.53.0)(prettier@3.0.3)(typescript@5.2.2):
+  /@mizdra/eslint-config-mizdra@2.1.0-alpha.0(eslint@8.57.0)(prettier@3.0.3)(typescript@5.2.2):
     resolution: {integrity: sha512-3BQ/CBBfe128WRbsrDDLbNmx3nCuKLt9UL1xqf16v2nZwlYLjOpQ8eS3XPADiUOkPlcjbKu0DCrZ1ubG9TL1MA==}
     engines: {node: '>=16.0.0'}
     peerDependencies:
@@ -464,15 +464,15 @@ packages:
       typescript:
         optional: true
     dependencies:
-      '@typescript-eslint/eslint-plugin': 5.59.2(@typescript-eslint/parser@5.59.2)(eslint@8.53.0)(typescript@5.2.2)
-      '@typescript-eslint/parser': 5.59.2(eslint@8.53.0)(typescript@5.2.2)
-      eslint: 8.53.0
-      eslint-config-prettier: 9.0.0(eslint@8.53.0)
-      eslint-plugin-import: /eslint-plugin-i@2.29.0(@typescript-eslint/parser@5.59.2)(eslint@8.53.0)
-      eslint-plugin-n: 15.7.0(eslint@8.53.0)
-      eslint-plugin-react: 7.32.2(eslint@8.53.0)
-      eslint-plugin-react-hooks: 4.6.0(eslint@8.53.0)
-      eslint-plugin-unicorn: 49.0.0(eslint@8.53.0)
+      '@typescript-eslint/eslint-plugin': 5.59.2(@typescript-eslint/parser@5.59.2)(eslint@8.57.0)(typescript@5.2.2)
+      '@typescript-eslint/parser': 5.59.2(eslint@8.57.0)(typescript@5.2.2)
+      eslint: 8.57.0
+      eslint-config-prettier: 9.0.0(eslint@8.57.0)
+      eslint-plugin-import: /eslint-plugin-i@2.29.0(@typescript-eslint/parser@5.59.2)(eslint@8.57.0)
+      eslint-plugin-n: 15.7.0(eslint@8.57.0)
+      eslint-plugin-react: 7.32.2(eslint@8.57.0)
+      eslint-plugin-react-hooks: 4.6.0(eslint@8.57.0)
+      eslint-plugin-unicorn: 49.0.0(eslint@8.57.0)
       prettier: 3.0.3
       typescript: 5.2.2
     transitivePeerDependencies:
@@ -690,7 +690,7 @@ packages:
       '@types/yargs-parser': 21.0.2
     dev: true
 
-  /@typescript-eslint/eslint-plugin@5.59.2(@typescript-eslint/parser@5.59.2)(eslint@8.53.0)(typescript@5.2.2):
+  /@typescript-eslint/eslint-plugin@5.59.2(@typescript-eslint/parser@5.59.2)(eslint@8.57.0)(typescript@5.2.2):
     resolution: {integrity: sha512-yVrXupeHjRxLDcPKL10sGQ/QlVrA8J5IYOEWVqk0lJaSZP7X5DfnP7Ns3cc74/blmbipQ1htFNVGsHX6wsYm0A==}
     engines: {node: ^12.22.0 || ^14.17.0 || >=16.0.0}
     peerDependencies:
@@ -702,12 +702,12 @@ packages:
         optional: true
     dependencies:
       '@eslint-community/regexpp': 4.10.0
-      '@typescript-eslint/parser': 5.59.2(eslint@8.53.0)(typescript@5.2.2)
+      '@typescript-eslint/parser': 5.59.2(eslint@8.57.0)(typescript@5.2.2)
       '@typescript-eslint/scope-manager': 5.59.2
-      '@typescript-eslint/type-utils': 5.59.2(eslint@8.53.0)(typescript@5.2.2)
-      '@typescript-eslint/utils': 5.59.2(eslint@8.53.0)(typescript@5.2.2)
+      '@typescript-eslint/type-utils': 5.59.2(eslint@8.57.0)(typescript@5.2.2)
+      '@typescript-eslint/utils': 5.59.2(eslint@8.57.0)(typescript@5.2.2)
       debug: 4.3.4
-      eslint: 8.53.0
+      eslint: 8.57.0
       grapheme-splitter: 1.0.4
       ignore: 5.2.4
       natural-compare-lite: 1.4.0
@@ -718,7 +718,7 @@ packages:
       - supports-color
     dev: true
 
-  /@typescript-eslint/parser@5.59.2(eslint@8.53.0)(typescript@5.2.2):
+  /@typescript-eslint/parser@5.59.2(eslint@8.57.0)(typescript@5.2.2):
     resolution: {integrity: sha512-uq0sKyw6ao1iFOZZGk9F8Nro/8+gfB5ezl1cA06SrqbgJAt0SRoFhb9pXaHvkrxUpZaoLxt8KlovHNk8Gp6/HQ==}
     engines: {node: ^12.22.0 || ^14.17.0 || >=16.0.0}
     peerDependencies:
@@ -732,7 +732,7 @@ packages:
       '@typescript-eslint/types': 5.59.2
       '@typescript-eslint/typescript-estree': 5.59.2(typescript@5.2.2)
       debug: 4.3.4
-      eslint: 8.53.0
+      eslint: 8.57.0
       typescript: 5.2.2
     transitivePeerDependencies:
       - supports-color
@@ -746,7 +746,7 @@ packages:
       '@typescript-eslint/visitor-keys': 5.59.2
     dev: true
 
-  /@typescript-eslint/type-utils@5.59.2(eslint@8.53.0)(typescript@5.2.2):
+  /@typescript-eslint/type-utils@5.59.2(eslint@8.57.0)(typescript@5.2.2):
     resolution: {integrity: sha512-b1LS2phBOsEy/T381bxkkywfQXkV1dWda/z0PhnIy3bC5+rQWQDS7fk9CSpcXBccPY27Z6vBEuaPBCKCgYezyQ==}
     engines: {node: ^12.22.0 || ^14.17.0 || >=16.0.0}
     peerDependencies:
@@ -757,9 +757,9 @@ packages:
         optional: true
     dependencies:
       '@typescript-eslint/typescript-estree': 5.59.2(typescript@5.2.2)
-      '@typescript-eslint/utils': 5.59.2(eslint@8.53.0)(typescript@5.2.2)
+      '@typescript-eslint/utils': 5.59.2(eslint@8.57.0)(typescript@5.2.2)
       debug: 4.3.4
-      eslint: 8.53.0
+      eslint: 8.57.0
       tsutils: 3.21.0(typescript@5.2.2)
       typescript: 5.2.2
     transitivePeerDependencies:
@@ -792,19 +792,19 @@ packages:
       - supports-color
     dev: true
 
-  /@typescript-eslint/utils@5.59.2(eslint@8.53.0)(typescript@5.2.2):
+  /@typescript-eslint/utils@5.59.2(eslint@8.57.0)(typescript@5.2.2):
     resolution: {integrity: sha512-kSuF6/77TZzyGPhGO4uVp+f0SBoYxCDf+lW3GKhtKru/L8k/Hd7NFQxyWUeY7Z/KGB2C6Fe3yf2vVi4V9TsCSQ==}
     engines: {node: ^12.22.0 || ^14.17.0 || >=16.0.0}
     peerDependencies:
       eslint: ^6.0.0 || ^7.0.0 || ^8.0.0
     dependencies:
-      '@eslint-community/eslint-utils': 4.4.0(eslint@8.53.0)
+      '@eslint-community/eslint-utils': 4.4.0(eslint@8.57.0)
       '@types/json-schema': 7.0.14
       '@types/semver': 7.3.13
       '@typescript-eslint/scope-manager': 5.59.2
       '@typescript-eslint/types': 5.59.2
       '@typescript-eslint/typescript-estree': 5.59.2(typescript@5.2.2)
-      eslint: 8.53.0
+      eslint: 8.57.0
       eslint-scope: 5.1.1
       semver: 7.5.4
     transitivePeerDependencies:
@@ -1475,13 +1475,13 @@ packages:
     engines: {node: '>=10'}
     dev: true
 
-  /eslint-config-prettier@9.0.0(eslint@8.53.0):
+  /eslint-config-prettier@9.0.0(eslint@8.57.0):
     resolution: {integrity: sha512-IcJsTkJae2S35pRsRAwoCE+925rJJStOdkKnLVgtE+tEpqU0EVVM7OqrwxqgptKdX29NUwC82I5pXsGFIgSevw==}
     hasBin: true
     peerDependencies:
       eslint: '>=7.0.0'
     dependencies:
-      eslint: 8.53.0
+      eslint: 8.57.0
     dev: true
 
   /eslint-formatter-codeframe@7.32.1:
@@ -1502,7 +1502,7 @@ packages:
       - supports-color
     dev: true
 
-  /eslint-module-utils@2.8.0(@typescript-eslint/parser@5.59.2)(eslint-import-resolver-node@0.3.9)(eslint@8.53.0):
+  /eslint-module-utils@2.8.0(@typescript-eslint/parser@5.59.2)(eslint-import-resolver-node@0.3.9)(eslint@8.57.0):
     resolution: {integrity: sha512-aWajIYfsqCKRDgUfjEXNN/JlrzauMuSEy5sbd7WXbtW3EH6A6MpwEh42c7qD+MqQo9QMJ6fWLAeIJynx0g6OAw==}
     engines: {node: '>=4'}
     peerDependencies:
@@ -1523,26 +1523,26 @@ packages:
       eslint-import-resolver-webpack:
         optional: true
     dependencies:
-      '@typescript-eslint/parser': 5.59.2(eslint@8.53.0)(typescript@5.2.2)
+      '@typescript-eslint/parser': 5.59.2(eslint@8.57.0)(typescript@5.2.2)
       debug: 3.2.7
-      eslint: 8.53.0
+      eslint: 8.57.0
       eslint-import-resolver-node: 0.3.9
     transitivePeerDependencies:
       - supports-color
     dev: true
 
-  /eslint-plugin-es@4.1.0(eslint@8.53.0):
+  /eslint-plugin-es@4.1.0(eslint@8.57.0):
     resolution: {integrity: sha512-GILhQTnjYE2WorX5Jyi5i4dz5ALWxBIdQECVQavL6s7cI76IZTDWleTHkxz/QT3kvcs2QlGHvKLYsSlPOlPXnQ==}
     engines: {node: '>=8.10.0'}
     peerDependencies:
       eslint: '>=4.19.1'
     dependencies:
-      eslint: 8.53.0
+      eslint: 8.57.0
       eslint-utils: 2.1.0
       regexpp: 3.2.0
     dev: true
 
-  /eslint-plugin-i@2.29.0(@typescript-eslint/parser@5.59.2)(eslint@8.53.0):
+  /eslint-plugin-i@2.29.0(@typescript-eslint/parser@5.59.2)(eslint@8.57.0):
     resolution: {integrity: sha512-slGeTS3GQzx9267wLJnNYNO8X9EHGsc75AKIAFvnvMYEcTJKotPKL1Ru5PIGVHIVet+2DsugePWp8Oxpx8G22w==}
     engines: {node: '>=12'}
     peerDependencies:
@@ -1550,9 +1550,9 @@ packages:
     dependencies:
       debug: 3.2.7
       doctrine: 2.1.0
-      eslint: 8.53.0
+      eslint: 8.57.0
       eslint-import-resolver-node: 0.3.9
-      eslint-module-utils: 2.8.0(@typescript-eslint/parser@5.59.2)(eslint-import-resolver-node@0.3.9)(eslint@8.53.0)
+      eslint-module-utils: 2.8.0(@typescript-eslint/parser@5.59.2)(eslint-import-resolver-node@0.3.9)(eslint@8.57.0)
       get-tsconfig: 4.7.2
       is-glob: 4.0.3
       minimatch: 3.1.2
@@ -1565,16 +1565,16 @@ packages:
       - supports-color
     dev: true
 
-  /eslint-plugin-n@15.7.0(eslint@8.53.0):
+  /eslint-plugin-n@15.7.0(eslint@8.57.0):
     resolution: {integrity: sha512-jDex9s7D/Qial8AGVIHq4W7NswpUD5DPDL2RH8Lzd9EloWUuvUkHfv4FRLMipH5q2UtyurorBkPeNi1wVWNh3Q==}
     engines: {node: '>=12.22.0'}
     peerDependencies:
       eslint: '>=7.0.0'
     dependencies:
       builtins: 5.0.1
-      eslint: 8.53.0
-      eslint-plugin-es: 4.1.0(eslint@8.53.0)
-      eslint-utils: 3.0.0(eslint@8.53.0)
+      eslint: 8.57.0
+      eslint-plugin-es: 4.1.0(eslint@8.57.0)
+      eslint-utils: 3.0.0(eslint@8.57.0)
       ignore: 5.2.4
       is-core-module: 2.13.1
       minimatch: 3.1.2
@@ -1582,16 +1582,16 @@ packages:
       semver: 7.5.4
     dev: true
 
-  /eslint-plugin-react-hooks@4.6.0(eslint@8.53.0):
+  /eslint-plugin-react-hooks@4.6.0(eslint@8.57.0):
     resolution: {integrity: sha512-oFc7Itz9Qxh2x4gNHStv3BqJq54ExXmfC+a1NjAta66IAN87Wu0R/QArgIS9qKzX3dXKPI9H5crl9QchNMY9+g==}
     engines: {node: '>=10'}
     peerDependencies:
       eslint: ^3.0.0 || ^4.0.0 || ^5.0.0 || ^6.0.0 || ^7.0.0 || ^8.0.0-0
     dependencies:
-      eslint: 8.53.0
+      eslint: 8.57.0
     dev: true
 
-  /eslint-plugin-react@7.32.2(eslint@8.53.0):
+  /eslint-plugin-react@7.32.2(eslint@8.57.0):
     resolution: {integrity: sha512-t2fBMa+XzonrrNkyVirzKlvn5RXzzPwRHtMvLAtVZrt8oxgnTQaYbU6SXTOO1mwQgp1y5+toMSKInnzGr0Knqg==}
     engines: {node: '>=4'}
     peerDependencies:
@@ -1601,7 +1601,7 @@ packages:
       array.prototype.flatmap: 1.3.1
       array.prototype.tosorted: 1.1.1
       doctrine: 2.1.0
-      eslint: 8.53.0
+      eslint: 8.57.0
       estraverse: 5.3.0
       jsx-ast-utils: 3.3.3
       minimatch: 3.1.2
@@ -1615,17 +1615,17 @@ packages:
       string.prototype.matchall: 4.0.8
     dev: true
 
-  /eslint-plugin-unicorn@49.0.0(eslint@8.53.0):
+  /eslint-plugin-unicorn@49.0.0(eslint@8.57.0):
     resolution: {integrity: sha512-0fHEa/8Pih5cmzFW5L7xMEfUTvI9WKeQtjmKpTUmY+BiFCDxkxrTdnURJOHKykhtwIeyYsxnecbGvDCml++z4Q==}
     engines: {node: '>=16'}
     peerDependencies:
       eslint: '>=8.52.0'
     dependencies:
       '@babel/helper-validator-identifier': 7.22.20
-      '@eslint-community/eslint-utils': 4.4.0(eslint@8.53.0)
+      '@eslint-community/eslint-utils': 4.4.0(eslint@8.57.0)
       ci-info: 3.9.0
       clean-regexp: 1.0.0
-      eslint: 8.53.0
+      eslint: 8.57.0
       esquery: 1.5.0
       indent-string: 4.0.0
       is-builtin-module: 3.2.1
@@ -1661,13 +1661,13 @@ packages:
       eslint-visitor-keys: 1.3.0
     dev: true
 
-  /eslint-utils@3.0.0(eslint@8.53.0):
+  /eslint-utils@3.0.0(eslint@8.57.0):
     resolution: {integrity: sha512-uuQC43IGctw68pJA1RgbQS8/NP7rch6Cwd4j3ZBtgo4/8Flj4eGE7ZYSZRN3iq5pVUv6GPdW5Z1RFleo84uLDA==}
     engines: {node: ^10.0.0 || ^12.0.0 || >= 14.0.0}
     peerDependencies:
       eslint: '>=5'
     dependencies:
-      eslint: 8.53.0
+      eslint: 8.57.0
       eslint-visitor-keys: 2.1.0
     dev: true
 
@@ -1681,26 +1681,21 @@ packages:
     engines: {node: '>=10'}
     dev: true
 
-  /eslint-visitor-keys@3.4.1:
-    resolution: {integrity: sha512-pZnmmLwYzf+kWaM/Qgrvpen51upAktaaiI01nsJD/Yr3lMOdNtq0cxkrrg16w64VtisN6okbs7Q8AfGqj4c9fA==}
-    engines: {node: ^12.22.0 || ^14.17.0 || >=16.0.0}
-    dev: true
-
   /eslint-visitor-keys@3.4.3:
     resolution: {integrity: sha512-wpc+LXeiyiisxPlEkUzU6svyS1frIO3Mgxj1fdy7Pm8Ygzguax2N3Fa/D/ag1WqbOprdI+uY6wMUl8/a2G+iag==}
     engines: {node: ^12.22.0 || ^14.17.0 || >=16.0.0}
     dev: true
 
-  /eslint@8.53.0:
-    resolution: {integrity: sha512-N4VuiPjXDUa4xVeV/GC/RV3hQW9Nw+Y463lkWaKKXKYMvmRiRDAtfpuPFLN+E1/6ZhyR8J2ig+eVREnYgUsiag==}
+  /eslint@8.57.0:
+    resolution: {integrity: sha512-dZ6+mexnaTIbSBZWgou51U6OmzIhYM2VcNdtiTtI7qPNZm35Akpr0f6vtw3w1Kmn5PYo+tZVfh13WrhpS6oLqQ==}
     engines: {node: ^12.22.0 || ^14.17.0 || >=16.0.0}
     hasBin: true
     dependencies:
-      '@eslint-community/eslint-utils': 4.4.0(eslint@8.53.0)
+      '@eslint-community/eslint-utils': 4.4.0(eslint@8.57.0)
       '@eslint-community/regexpp': 4.10.0
-      '@eslint/eslintrc': 2.1.3
-      '@eslint/js': 8.53.0
-      '@humanwhocodes/config-array': 0.11.13
+      '@eslint/eslintrc': 2.1.4
+      '@eslint/js': 8.57.0
+      '@humanwhocodes/config-array': 0.11.14
       '@humanwhocodes/module-importer': 1.0.1
       '@nodelib/fs.walk': 1.2.8
       '@ungap/structured-clone': 1.2.0
diff --git a/src/__snapshots__/core.test.ts.snap b/src/__snapshots__/core.test.ts.snap
index fa6b66df..bf9da771 100644
--- a/src/__snapshots__/core.test.ts.snap
+++ b/src/__snapshots__/core.test.ts.snap
@@ -69,6 +69,63 @@ exports[`Core > disablePerLine 1`] = `
 let a = 1;"
 `;
 
+exports[`Core > flat config 1`] = `
+[
+  {
+    "errorCount": 1,
+    "filePath": "<fixture>/src/.index.js",
+    "messages": [
+      {
+        "ruleId": "prefer-const",
+        "severity": 2,
+      },
+    ],
+    "warningCount": 0,
+  },
+  {
+    "errorCount": 1,
+    "filePath": "<fixture>/src/index.js",
+    "messages": [
+      {
+        "ruleId": "prefer-const",
+        "severity": 2,
+      },
+    ],
+    "warningCount": 0,
+  },
+  {
+    "errorCount": 1,
+    "filePath": "<fixture>/src/index.jsx",
+    "messages": [
+      {
+        "ruleId": "prefer-const",
+        "severity": 2,
+      },
+    ],
+    "warningCount": 0,
+  },
+  {
+    "errorCount": 1,
+    "filePath": "<fixture>/src/index.mjs",
+    "messages": [
+      {
+        "ruleId": "prefer-const",
+        "severity": 2,
+      },
+    ],
+    "warningCount": 0,
+  },
+]
+`;
+
+exports[`Core > flat config 2`] = `"const a = 1;"`;
+
+exports[`Core > flat config 3`] = `"const a = 1;"`;
+
+exports[`Core > flat config 4`] = `"const a = 1;"`;
+
+exports[`Core > flat config 5`] = `"const a = 1;"`;
+
 exports[`Core > lint > returns lint results 1`] = `
 [
   {
diff --git a/src/cli/run.ts b/src/cli/run.ts
index d4751379..cce6bd3e 100644
--- a/src/cli/run.ts
+++ b/src/cli/run.ts
@@ -31,10 +31,7 @@ export async function run(options: Options) {
   }
   const parsedCLIOptions = parseArgv(options.argv);
   const usingFlatConfig = await shouldUseFlatConfig();
-  if (usingFlatConfig) {
-    throw new Error('Flat Config is not yet supported.'); // TODO: support flat config
-  }
-  const config = translateCLIOptions(parsedCLIOptions, 'eslintrc'); // TODO: support flat config
+  const config = translateCLIOptions(parsedCLIOptions, usingFlatConfig ? 'flat' : 'eslintrc');
 
   // Directly executing the Core API will hog the main thread and halt the spinner.
   // So we wrap it with comlink and run it on the Worker.
diff --git a/src/config.ts b/src/config.ts
index 2ebd04ba..7dea6406 100644
--- a/src/config.ts
+++ b/src/config.ts
@@ -1,4 +1,4 @@
-import type { LegacyESLint } from 'eslint/use-at-your-own-risk';
+import type { LegacyESLint, FlatESLint } from 'eslint/use-at-your-own-risk';
 import { cliOptionsDefaults, ParsedCLIOptions } from './cli/parse-argv.js';
 import { DeepPartial } from './util/type-check.js';
 type LegacyESLintOptions = { type: 'eslintrc' } & Pick<
@@ -14,8 +14,12 @@ type LegacyESLintOptions = { type: 'eslintrc' } & Pick<
   | 'cwd'
   | 'resolvePluginsRelativeTo'
 >;
+type FlatESLintOptions = { type: 'flat' } & Pick<
+  FlatESLint.Options,
+  'overrideConfigFile' | 'cache' | 'cacheLocation' | 'overrideConfig' | 'cwd'
+>;
 
-export type ESLintOptions = LegacyESLintOptions; // TODO: support flat config
+export type ESLintOptions = LegacyESLintOptions | FlatESLintOptions;
 
 /** The config of eslint-interactive */
 export type Config = {
@@ -47,7 +51,17 @@ export function translateCLIOptions(options: ParsedCLIOptions, eslintOptionsType
       },
     };
   } else if (eslintOptionsType === 'flat') {
-    throw new Error('Flat config is not supported yet');
+    return {
+      patterns: options.patterns,
+      formatterName: options.formatterName,
+      quiet: options.quiet,
+      eslintOptions: {
+        type: 'flat',
+        overrideConfigFile: options.overrideConfigFile,
+        cache: options.cache,
+        cacheLocation: options.cacheLocation,
+      },
+    };
   } else {
     throw new Error(`Unexpected configType: ${String(eslintOptionsType)}`);
   }
@@ -81,12 +95,9 @@ export type NormalizedConfig = {
 
 export function normalizeConfig(config: Config): NormalizedConfig {
   const cwd = config.cwd ?? configDefaults.cwd;
-  return {
-    patterns: config.patterns,
-    formatterName: config.formatterName ?? configDefaults.formatterName,
-    quiet: config.quiet ?? configDefaults.quiet,
-    cwd,
-    eslintOptions: {
+  let eslintOptions: NormalizedConfig['eslintOptions'];
+  if (config.eslintOptions.type === 'eslintrc') {
+    eslintOptions = {
       type: 'eslintrc',
       useEslintrc: config.eslintOptions.useEslintrc ?? configDefaults.eslintOptions.useEslintrc,
       overrideConfigFile: config.eslintOptions.overrideConfigFile ?? configDefaults.eslintOptions.overrideConfigFile,
@@ -99,6 +110,22 @@ export function normalizeConfig(config: Config): NormalizedConfig {
       cwd,
       resolvePluginsRelativeTo:
         config.eslintOptions.resolvePluginsRelativeTo ?? configDefaults.eslintOptions.resolvePluginsRelativeTo,
-    },
+    };
+  } else {
+    eslintOptions = {
+      type: 'flat',
+      overrideConfigFile: config.eslintOptions.overrideConfigFile ?? configDefaults.eslintOptions.overrideConfigFile,
+      cache: config.eslintOptions.cache ?? configDefaults.eslintOptions.cache,
+      cacheLocation: config.eslintOptions.cacheLocation ?? configDefaults.eslintOptions.cacheLocation,
+      overrideConfig: config.eslintOptions.overrideConfig ?? configDefaults.eslintOptions.overrideConfig,
+      cwd,
+    };
+  }
+  return {
+    patterns: config.patterns,
+    formatterName: config.formatterName ?? configDefaults.formatterName,
+    quiet: config.quiet ?? configDefaults.quiet,
+    cwd,
+    eslintOptions,
   };
 }
diff --git a/src/core.test.ts b/src/core.test.ts
index e49f1263..314965af 100644
--- a/src/core.test.ts
+++ b/src/core.test.ts
@@ -272,4 +272,44 @@ describe('Core', () => {
     await undo();
     expect(await readFile(iff.paths['src/no-unused-vars.js'], 'utf-8')).toEqual(original);
   });
+  test('flat config', async () => {
+    const iff = await createIFF({
+      'src/index.js': 'let a = 1;',
+      'src/index.mjs': 'let a = 1;',
+      'src/index.jsx': 'let a = 1;',
+      'src/.index.js': 'let a = 1;',
+      'eslint.config.js': dedent`
+        export default [
+          {
+            files: ['**/*.js', '**/*.mjs', '**/*.jsx'],
+            languageOptions: {
+              sourceType: 'module',
+              ecmaVersion: 2020,
+              parserOptions: {
+                ecmaFeatures: {
+                  jsx: true,
+                },
+              },
+            },
+            rules: { 'prefer-const': 'error' },
+          },
+        ];
+      `,
+      'package.json': '{ "type": "module" }',
+    });
+    const core = new Core({
+      patterns: ['src'],
+      cwd: iff.rootDir,
+      eslintOptions: {
+        type: 'flat',
+      },
+    });
+    const results = await core.lint();
+    expect(normalizeResults(results, iff.rootDir)).toMatchSnapshot();
+    await core.applyAutoFixes(results, ['prefer-const']);
+    expect(await readFile(iff.paths['src/index.js'], 'utf-8')).toMatchSnapshot();
+    expect(await readFile(iff.paths['src/index.mjs'], 'utf-8')).toMatchSnapshot();
+    expect(await readFile(iff.paths['src/index.jsx'], 'utf-8')).toMatchSnapshot();
+    expect(await readFile(iff.paths['src/.index.js'], 'utf-8')).toMatchSnapshot();
+  });
 });
diff --git a/src/core.ts b/src/core.ts
index 452e4cd2..d3288951 100644
--- a/src/core.ts
+++ b/src/core.ts
@@ -20,7 +20,7 @@ import {
 import { format } from './formatter/index.js';
 import { filterResultsByRuleId } from './util/eslint.js';
 
-const { LegacyESLint } = eslintPkg;
+const { LegacyESLint, FlatESLint } = eslintPkg;
 
 /**
  * Generate results to undo.
@@ -46,12 +46,13 @@ export class Core {
 
   constructor(config: Config) {
     this.config = normalizeConfig(config);
-    const { type, ...eslintOptions } = this.config.eslintOptions;
-    if (type === 'eslintrc') {
-      this.eslint = new LegacyESLint(eslintOptions);
+    const eslintOptions = this.config.eslintOptions;
+    if (eslintOptions.type === 'eslintrc') {
+      const { type, ...rest } = eslintOptions;
+      this.eslint = new LegacyESLint(rest);
     } else {
-      // TODO: support flat config
-      throw new Error(`Flat Config is not yet supported.`);
+      const { type, ...rest } = eslintOptions;
+      this.eslint = new FlatESLint(rest);
     }
   }
 
@@ -190,13 +191,18 @@ export class Core {
   ): Promise<Undo> {
     // NOTE: Extract only necessary results and files for performance
     const filteredResultsOfLint = filterResultsByRuleId(resultsOfLint, ruleIds);
-    const linter = new Linter({ configType: 'eslintrc' });
+    const linter = new Linter({ configType: this.config.eslintOptions.type });
 
     // eslint-disable-next-line prefer-const
     for (let { filePath, source } of filteredResultsOfLint) {
       if (!source) throw new Error('Source code is required to apply fixes.');
-      // eslint-disable-next-line no-await-in-loop
-      const config: Linter.Config = await this.eslint.calculateConfigForFile(filePath);
+      const config: Linter.Config | Linter.FlatConfig[] =
+        this.config.eslintOptions.type === 'eslintrc'
+          ? // eslint-disable-next-line no-await-in-loop
+            await this.eslint.calculateConfigForFile(filePath)
+          : // NOTE: For some reason, if files is not specified, it will not match .jsx
+            // eslint-disable-next-line no-await-in-loop
+            [{ ...(await this.eslint.calculateConfigForFile(filePath)), files: ['**/*.*', '**/*'] }];
 
       const fixedResult = verifyAndFix(linter, source, config, filePath, ruleIds, fixCreator);
 
diff --git a/src/eslint/linter.ts b/src/eslint/linter.ts
index f4c65e9c..8677ead0 100644
--- a/src/eslint/linter.ts
+++ b/src/eslint/linter.ts
@@ -27,7 +27,7 @@ type FixedResult = {
 export function verifyAndFix(
   linter: Linter,
   text: string,
-  config: Linter.Config,
+  config: Linter.Config | Linter.FlatConfig[],
   filePath: string,
   ruleIds: string[],
   fixCreator: (context: FixContext) => Rule.Fix[],