feat(eslint): migrate from tseslint.config to eslint.defineConfig

- the `config(...)` utility function from tseslint was deprecated in favor of ESLint core's `defineConfig(...)`, see: https://typescript-eslint.io/packages/typescript-eslint/#config-deprecated
- update documentation

BREAKING CHANGE: The `boehringer.config(...)` utility function has been removed in favor of ESLint core’s `defineConfig(...)`. Replace `boehringer.config(...)` with `defineConfig(...)` from `eslint/config`

```diff
import boehringer from '@boehringer-ingelheim/eslint-config';
+ import { defineConfig } from 'eslint/config';

- export default boehringer.config(
+ export default defineConfig(
  boehringer.configs.strict,
  {
    rules: {
      'no-empty-function': 'off',
    },
  }
);
```

Author: SimonGolms

.nvmrc

@@ -1 +1 @@
-v22
+v22.18

LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2023 Boehringer Ingelheim
+Copyright (c) 2025 Boehringer Ingelheim
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -25,24 +25,22 @@ Create or update the `eslint.config.mjs` (`eslint.config.cjs` is also possible i
 
 ```js
 import boehringer from '@boehringer-ingelheim/eslint-config';
+import { defineConfig } from 'eslint/config';
 
-export default boehringer.config(
+export default defineConfig(
   boehringer.configs.strict
 )
 ```
 
-#### `boehringer.config(...)`
-
-This function is a re-export for the config-helper of typescript eslint (See [docs](https://github.com/typescript-eslint/typescript-eslint/blob/a383d5022b81eaf65ce7b0946491444c6eaa28e3/docs/packages/TypeScript_ESLint.mdx#config)).
-
-##### Extend or Override configuration
+#### Extend or Override configuration
 
 This is not recommended as the goal is to have similar code stylings in all projects, but if for some reason you need to add or change the configuration, it is possible in the following way:
 
 ```js
 import boehringer from '@boehringer-ingelheim/eslint-config';
+import { defineConfig } from 'eslint/config';
 
-export default boehringer.config(
+export default defineConfig(
   boehringer.configs.strict, 
   {
     rules: {
@@ -60,8 +58,9 @@ It is recommended to use this function to ensure that your `.gitignore` file is
 
 ```js
 import boehringer from '@boehringer-ingelheim/eslint-config';
+import { defineConfig } from 'eslint/config';
 
-export default boehringer.config(
+export default defineConfig(
   boehringer.includeIgnoreFile(), // default value '.gitignore'
   boehringer.configs.strict,
 );
@@ -71,8 +70,9 @@ or in case you have a different paths to your `.gitignore` file(s):
 
 ```js
 import boehringer from '@boehringer-ingelheim/eslint-config';
+import { defineConfig } from 'eslint/config';
 
-export default boehringer.config(
+export default defineConfig(
   boehringer.includeIgnoreFile('./backend/.gitignore'),
   boehringer.includeIgnoreFile('./frontend/.gitignore'),
   boehringer.configs.strict,
@@ -95,8 +95,9 @@ Opinionated Options that differ from the standard/recommended ESLint configurati
 
 ```js
 import boehringer from '@boehringer-ingelheim/eslint-config';
+import { defineConfig } from 'eslint/config';
 
-export default boehringer.config(
+export default defineConfig(
   boehringer.configs.base
 )
 ```
@@ -117,8 +118,9 @@ This configuration also sets up the TypeScript parser [`@typescript-eslint/parse
 
 ```js
 import boehringer from '@boehringer-ingelheim/eslint-config';
+import { defineConfig } from 'eslint/config';
 
-export default boehringer.config(
+export default defineConfig(
   boehringer.configs.base,
   boehringer.configs.local
 );
@@ -130,8 +132,9 @@ This shared ESLint configuration configures or disables some rules for a better
 
 ```js
 import boehringer from '@boehringer-ingelheim/eslint-config';
+import { defineConfig } from 'eslint/config';
 
-export default boehringer.config(
+export default defineConfig(
   boehringer.configs.strict
 );
 ```
@@ -142,8 +145,9 @@ This shared ESLint configuration extends the [base configuration](#base) and add
 
 ```js
 import boehringer from '@boehringer-ingelheim/eslint-config';
+import { defineConfig } from 'eslint/config';
 
-export default boehringer.config(
+export default defineConfig(
   boehringer.configs.strict,
   boehringer.configs.react
 );
@@ -163,8 +167,9 @@ Additionally in restricts the usage of enums using [`no-restricted-syntax`](http
 
 ```js
 import boehringer from '@boehringer-ingelheim/eslint-config';
+import { defineConfig } from 'eslint/config';
 
-export default boehringer.config(
+export default defineConfig(
   boehringer.configs.strict,
   boehringer.configs.nextjs
 );
@@ -176,8 +181,9 @@ This shared ESLint configuration is specifically tailored for [Next.js](https://
 
 ```js
 import boehringer from '@boehringer-ingelheim/eslint-config';
+import { defineConfig } from 'eslint/config';
 
-export default boehringer.config(
+export default defineConfig(
   boehringer.configs.strict,
   boehringer.configs.playwright
 );
@@ -187,12 +193,13 @@ or for specific files only:
 
 ```js
 import boehringer from '@boehringer-ingelheim/eslint-config';
+import { defineConfig } from 'eslint/config';
 
-export default boehringer.config(
+export default defineConfig(
   boehringer.configs.strict,
   {
     files: ['src/**/*.test.{ts,tsx}'],
-    ...(await boehringer.configs.playwright)[0],
+    ...boehringer.configs.playwright[0],
   },
 );
 ```
@@ -207,8 +214,9 @@ This shared ESLint configuration is designed to enforce best practices and recom
 
 ```js
 import boehringer from '@boehringer-ingelheim/eslint-config';
+import { defineConfig } from 'eslint/config';
 
-export default boehringer.config(
+export default defineConfig(
   boehringer.configs.strict,
   // possibly other configs,
   boehringer.configs.experimentalNamingConvention
@@ -222,8 +230,9 @@ This shared ESLint configuration is designed to enforce some naming conventions.
 ```js
 import boehringer from '@boehringer-ingelheim/eslint-config';
 import prettier from 'eslint-plugin-prettier/recommended';
+import { defineConfig } from 'eslint/config';
 
-export default boehringer.config(
+export default defineConfig(
   boehringer.configs.strict,
   // Following needs eslint-plugin-prettier to be installed as described by https://github.com/prettier/eslint-plugin-prettier
   // Should be second to last
@@ -272,8 +281,9 @@ You can use the new [`allowDefaultProject`](https://typescript-eslint.io/package
 
 ```js
 import boehringer from '@boehringer-ingelheim/eslint-config';
+import { defineConfig } from 'eslint/config';
 
-export default boehringer.config(
+export default defineConfig(
   // other configs,
   {
     languageOptions: {
@@ -347,7 +357,7 @@ Give a ⭐️ if this project helped you!
 
 ## License
 
-Copyright © 2023 [Boehringer Ingelheim](https://github.com/boehringer-ingelheim).  
+Copyright © 2025 [Boehringer Ingelheim](https://github.com/boehringer-ingelheim).  
 This project is [MIT](https://github.com/boehringer-ingelheim/eslint-config/blob/master/LICENSE) licensed.
 
 ## Resources

configs/base.js

@@ -2,6 +2,7 @@ const eslint = require('@eslint/js');
 const importPlugin = require('eslint-plugin-import');
 const perfectionist = require('eslint-plugin-perfectionist');
 const sonarjs = require('eslint-plugin-sonarjs');
+const { defineConfig } = require('eslint/config');
 const tseslint = require('typescript-eslint');
 
 const {
@@ -10,7 +11,7 @@ const {
   SORT_INTERSECTION_TYPES_GROUPS,
 } = require('../lib/eslint-plugin-perfectionist.js');
 
-module.exports = tseslint.config(
+module.exports = defineConfig(
   eslint.configs.recommended,
   tseslint.configs.recommendedTypeChecked,
   tseslint.configs.stylisticTypeChecked,

configs/experimental-naming-convention.js

@@ -1,6 +1,6 @@
-const tseslint = require('typescript-eslint');
+const { defineConfig } = require('eslint/config');
 
-module.exports = tseslint.config({
+module.exports = defineConfig({
   rules: {
     '@typescript-eslint/naming-convention': [
       'error',

configs/local.js

@@ -1,7 +1,7 @@
+const { defineConfig } = require('eslint/config');
 const isCI = require('is-ci');
-const tseslint = require('typescript-eslint');
 
-module.exports = tseslint.config(
+module.exports = defineConfig(
   isCI
     ? {}
     : {

configs/nextjs.js

@@ -1,9 +1,9 @@
 const nextPlugin = require('@next/eslint-plugin-next');
-const tseslint = require('typescript-eslint');
+const { defineConfig } = require('eslint/config');
 
 const react = require('./react.js');
 
-module.exports = tseslint.config(
+module.exports = defineConfig(
   ...react,
   {
     plugins: {

configs/playwright.js

@@ -1,7 +1,7 @@
 const playwright = require('eslint-plugin-playwright');
-const tseslint = require('typescript-eslint');
+const { defineConfig } = require('eslint/config');
 
-module.exports = tseslint.config({
+module.exports = defineConfig({
   ...playwright.configs['flat/recommended'],
   rules: {
     /**

configs/prettier-disable.js

@@ -1,7 +1,7 @@
 const prettier = require('eslint-config-prettier');
-const tseslint = require('typescript-eslint');
+const { defineConfig } = require('eslint/config');
 
-module.exports = tseslint.config({
+module.exports = defineConfig({
   ...prettier,
   rules: {
     ...prettier.rules,

configs/react.js

@@ -2,13 +2,13 @@ const jsxA11y = require('eslint-plugin-jsx-a11y');
 const react = require('eslint-plugin-react');
 const reactHooks = require('eslint-plugin-react-hooks');
 const reactRefresh = require('eslint-plugin-react-refresh');
+const { defineConfig } = require('eslint/config');
 const globals = require('globals');
-const tseslint = require('typescript-eslint');
 
 const { SORT_IMPORTS_GROUPS } = require('../lib/eslint-plugin-perfectionist.js');
 const base = require('./base.js');
 
-module.exports = tseslint.config(
+module.exports = defineConfig(
   ...base,
   jsxA11y.flatConfigs.recommended,
   react.configs.flat.recommended,