diff --git a/README.md b/README.md
index ca3a08d..28f88f0 100644
--- a/README.md
+++ b/README.md
@@ -24,9 +24,9 @@ pnpm install defu
 ## Usage
 
 ```js
-import { defu } from 'defu'
+import { defu } from "defu";
 
-const options = defu(object, ...defaults)
+const options = defu(object, ...defaults);
 ```
 
 Leftmost arguments have more priority when assigning defaults.
@@ -37,16 +37,16 @@ Leftmost arguments have more priority when assigning defaults.
 - **source (Object):** The source object.
 
 ```js
-import { defu } from 'defu'
+import { defu } from "defu";
 
-console.log(defu({ 'a': { 'b': 2 } }, { 'a': { 'b': 1, 'c': 3 } }))
+console.log(defu({ a: { b: 2 } }, { a: { b: 1, c: 3 } }));
 // => { a: { b: 2, c: 3 } }
 ```
 
 ### Using with CommonJS
 
 ```js
-const { defu } = require('defu')
+const { defu } = require("defu");
 ```
 
 ## Custom Merger
@@ -58,16 +58,16 @@ This function accepts `obj` (source object), `key` and `value` (current value) a
 **Example:** Sum numbers instead of overriding
 
 ```js
-import { createDefu } from 'defu'
+import { createDefu } from "defu";
 
 const ext = createDefu((obj, key, value) => {
-  if (typeof obj[key] === 'number' && typeof value === 'number') {
-    obj[key] += value
-    return true
+  if (typeof obj[key] === "number" && typeof value === "number") {
+    obj[key] += value;
+    return true;
   }
-})
+});
 
-ext({ cost: 15 }, { cost: 10 }) // { cost: 25 }
+ext({ cost: 15 }, { cost: 10 }); // { cost: 25 }
 ```
 
 ## Function Merger
@@ -79,16 +79,19 @@ It can be useful for default values manipulation.
 **Example:** Filter some items from defaults (array) and add 20 to the count default value.
 
 ```js
-import { defuFn } from 'defu'
+import { defuFn } from "defu";
 
-defuFn({
-  ignore: (val) => val.filter(item => item !== 'dist'),
-  count: (count) => count + 20
- }, {
-   ignore: ['node_modules','dist'],
-   count: 10
- })
- /*
+defuFn(
+  {
+    ignore: (val) => val.filter((item) => item !== "dist"),
+    count: (count) => count + 20,
+  },
+  {
+    ignore: ["node_modules", "dist"],
+    count: 10,
+  },
+);
+/*
  {
     ignore: ['node_modules'],
     count: 30
@@ -133,8 +136,9 @@ defuArrayFn({
 - Nullish values ([`null`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/null) and [`undefined`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/undefined)) are skipped. Please use [defaults-deep](https://www.npmjs.com/package/defaults-deep) or [omit-deep](http://npmjs.com/package/omit-deep) or [lodash.defaultsdeep](https://www.npmjs.com/package/lodash.defaultsdeep) if you need to preserve or different behavior.
 - Assignment of `__proto__` and `constructor` keys will be skipped to prevent security issues with object pollution.
 - Will concat `array` values (if default property is defined)
+
 ```js
-console.log(defu({ array: ['b', 'c'] }, { array: ['a'] }))
+console.log(defu({ array: ["b", "c"] }, { array: ["a"] }));
 // => { array: ['b', 'c', 'a'] }
 ```
 
@@ -154,6 +158,7 @@ type Options = Defu<{ foo: 'bar' }, [{}, { bar: 'baz' }, { something: 42 }]>
 MIT. Made with 💖
 
 <!-- Refs -->
+
 [npm-version-src]: https://img.shields.io/npm/v/defu?style=flat&colorA=18181B&colorB=F0DB4F
 [npm-version-href]: https://npmjs.com/package/defu
 [npm-downloads-src]: https://img.shields.io/npm/dm/defu?style=flat&colorA=18181B&colorB=F0DB4F
diff --git a/package.json b/package.json
index 03ff2db..1c15788 100644
--- a/package.json
+++ b/package.json
@@ -21,6 +21,7 @@
     "build": "unbuild",
     "dev": "vitest",
     "lint": "eslint --ext .ts src && prettier -c src test",
+    "lint:fix": "eslint --ext .ts src --fix && prettier -w src test",
     "prepack": "pnpm build",
     "release": "pnpm test && changelogen --release && git push --follow-tags && pnpm publish",
     "test": "pnpm lint && pnpm vitest run",
diff --git a/renovate.json b/renovate.json
index a9971c8..57fe916 100644
--- a/renovate.json
+++ b/renovate.json
@@ -1,5 +1,3 @@
 {
-  "extends": [
-    "github>unjs/renovate-config"
-  ]
+  "extends": ["github>unjs/renovate-config"]
 }
diff --git a/src/defu.ts b/src/defu.ts
index 61c8264..af9ed88 100644
--- a/src/defu.ts
+++ b/src/defu.ts
@@ -9,7 +9,7 @@ function _defu<T>(
   baseObject: T,
   defaults: any,
   namespace = ".",
-  merger?: Merger
+  merger?: Merger,
 ): T {
   if (!isObject(defaults)) {
     return _defu(baseObject, {}, namespace, merger);
@@ -39,7 +39,7 @@ function _defu<T>(
         value,
         object[key],
         (namespace ? `${namespace}.` : "") + key.toString(),
-        merger
+        merger,
       );
     } else {
       object[key] = value;
@@ -62,10 +62,7 @@ export default defu;
 
 // Custom version with function merge support
 export const defuFn = createDefu((object, key, currentValue) => {
-  if (
-    typeof object[key] !== "undefined" &&
-    typeof currentValue === "function"
-  ) {
+  if (object[key] !== undefined && typeof currentValue === "function") {
     object[key] = currentValue(object[key]);
     return true;
   }
diff --git a/src/types.ts b/src/types.ts
index cfa7cc2..b17b22a 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -11,14 +11,14 @@ export type Merger = <T extends Input, K extends keyof T>(
   object: T,
   key: keyof T,
   value: T[K],
-  namespace: string
+  namespace: string,
 ) => any;
 
 type nullish = null | undefined | void;
 
 export type MergeObjects<
   Destination extends Input,
-  Defaults extends Input
+  Defaults extends Input,
 > = Destination extends Defaults
   ? Destination
   : Omit<Destination, keyof Destination & keyof Defaults> &
@@ -35,7 +35,7 @@ export type MergeObjects<
 
 export type Defu<
   S extends Input,
-  D extends Array<Input | IgnoredInput>
+  D extends Array<Input | IgnoredInput>,
 > = D extends [infer F, ...infer Rest]
   ? F extends Input
     ? Rest extends Array<Input | IgnoredInput>
@@ -50,7 +50,7 @@ export type Defu<
 
 export type DefuFn = <
   Source extends Input,
-  Defaults extends Array<Input | IgnoredInput>
+  Defaults extends Array<Input | IgnoredInput>,
 >(
   source: Source,
   ...defaults: Defaults
diff --git a/test/defu.test.ts b/test/defu.test.ts
index de980ba..0deddb2 100644
--- a/test/defu.test.ts
+++ b/test/defu.test.ts
@@ -87,7 +87,7 @@ describe("defu", () => {
 
   it("should not override Object prototype", () => {
     const payload = JSON.parse(
-      '{"constructor": {"prototype": {"isAdmin": true}}}'
+      '{"constructor": {"prototype": {"isAdmin": true}}}',
     );
     defu({}, payload);
     defu(payload, {});
@@ -119,7 +119,7 @@ describe("defu", () => {
       baz: number[];
     }
     expectTypeOf(
-      defu({} as SomeConfig, {} as SomeOtherConfig, {} as ThirdConfig)
+      defu({} as SomeConfig, {} as SomeOtherConfig, {} as ThirdConfig),
     ).toEqualTypeOf<ExpectedMergedType>();
   });
 
@@ -137,11 +137,11 @@ describe("defu", () => {
     let options: (SomeConfig & SomeOtherConfig) | undefined;
 
     expectTypeOf(
-      defu(options ?? {}, { foo: ["test"] }, { bar: ["test2"] }, {})
+      defu(options ?? {}, { foo: ["test"] }, { bar: ["test2"] }, {}),
     ).toEqualTypeOf<ExpectedMergedType>();
 
     expectTypeOf(
-      defu({ foo: ["test"] }, {}, { bar: ["test2"] }, {})
+      defu({ foo: ["test"] }, {}, { bar: ["test2"] }, {}),
     ).toEqualTypeOf<ExpectedMergedType>();
   });
 
@@ -167,8 +167,8 @@ describe("defu", () => {
         {
           ignore: ["node_modules", "dist"],
           num: 10,
-        }
-      )
+        },
+      ),
     ).toEqual({
       ignore: ["node_modules"],
       num: 20,
@@ -187,8 +187,8 @@ describe("defu", () => {
         {
           arr: ["a", "b"],
           num: 10,
-        }
-      )
+        },
+      ),
     ).toEqual({
       arr: ["c"],
       num,
diff --git a/tsconfig.json b/tsconfig.json
index f86f466..e8d5553 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -6,8 +6,5 @@
     "skipLibCheck": true,
     "declaration": true
   },
-  "include": [
-    "src",
-    "test"
-  ]
+  "include": ["src", "test"]
 }