diff --git a/index.js b/index.js
index c8a5feb..950532d 100644
--- a/index.js
+++ b/index.js
@@ -13,10 +13,10 @@
  * @param {string|Uint8Array|VFile} file
  */
 export function location(file) {
-  var value = String(file)
-  /** @type {Array.<number>} */
-  var indices = []
-  var search = /\r?\n|\r/g
+  const value = String(file)
+  /** @type {Array<number>} */
+  const indices = []
+  const search = /\r?\n|\r/g
 
   while (search.test(value)) {
     indices.push(search.lastIndex)
@@ -35,7 +35,7 @@ export function location(file) {
    * @returns {FullPoint}
    */
   function toPoint(offset) {
-    var index = -1
+    let index = -1
 
     if (offset > -1 && offset < indices[indices.length - 1]) {
       while (++index < indices.length) {
@@ -60,10 +60,10 @@ export function location(file) {
    * @returns {Offset}
    */
   function toOffset(point) {
-    var line = point && point.line
-    var column = point && point.column
+    const line = point && point.line
+    const column = point && point.column
     /** @type {number} */
-    var offset
+    let offset
 
     if (
       typeof line === 'number' &&
diff --git a/package.json b/package.json
index 45b6a93..76ac693 100644
--- a/package.json
+++ b/package.json
@@ -67,11 +67,7 @@
     "trailingComma": "none"
   },
   "xo": {
-    "prettier": true,
-    "rules": {
-      "no-var": "off",
-      "prefer-arrow-callback": "off"
-    }
+    "prettier": true
   },
   "remarkConfig": {
     "plugins": [
diff --git a/test.js b/test.js
index 9dcb896..b4dab22 100644
--- a/test.js
+++ b/test.js
@@ -3,7 +3,7 @@ import {VFile} from 'vfile'
 import {location} from './index.js'
 
 test('location()', function (t) {
-  var place = location('')
+  let place = location('')
 
   t.equals(
     typeof place.toOffset,
@@ -32,7 +32,7 @@ test('location()', function (t) {
   )
 
   t.test('place.toOffset(point)', function (t) {
-    var place = location('foo\nbar\nbaz')
+    const place = location('foo\nbar\nbaz')
 
     t.equals(
       place.toOffset({line: undefined, column: undefined}),
@@ -68,7 +68,7 @@ test('location()', function (t) {
   })
 
   t.test('place.toPoint(offset)', function (t) {
-    var place = location('foo\nbar\nbaz')
+    const place = location('foo\nbar\nbaz')
 
     t.deepEquals(
       place.toPoint(-1),
@@ -98,7 +98,7 @@ test('location()', function (t) {
   })
 
   t.test('other tests', function (t) {
-    var place = location('foo')
+    let place = location('foo')
 
     t.deepEquals(
       [place.toPoint(3), place.toPoint(4), place.toPoint(5)],