diff --git a/README.md b/README.md
index 72f7802..ac59992 100644
--- a/README.md
+++ b/README.md
@@ -2,24 +2,18 @@
 
 # remark-normalize-headings
 
-[![Build Status][travis-badge]][travis] [![Dependency Status][david-badge]][david]
+[![Build Status][travis-badge]][travis]
+[![Dependency Status][david-badge]][david]
 
-Providing multiple top-level headings per single Markdown document is confusing for tools that assume that there is only a single top-level heading that contains some meta-information (usually title) about the document.
+Providing multiple top-level headings per single Markdown document is confusing
+for tools that assume that there is only a single top-level heading that
+contains some meta-information (usually title) about the document.
 
-This [remark][] plugin makes sure that there is only one top-level heading in the document by adjusting headings depths accordingly.
+This [remark][] plugin makes sure that there is only one top-level heading in
+the document by adjusting headings depths accordingly.
 
 Originally extracted from [remark-man][].
 
-[remark]: https://github.com/wooorm/remark
-[remark-man]: https://github.com/wooorm/remark-man
-[mdast]: https://github.com/syntax-tree/mdast
-[mdast-normalize-headings]: https://github.com/eush77/mdast-normalize-headings
-
-[travis]: https://travis-ci.org/eush77/remark-normalize-headings
-[travis-badge]: https://travis-ci.org/eush77/remark-normalize-headings.svg
-[david]: https://david-dm.org/eush77/remark-normalize-headings
-[david-badge]: https://david-dm.org/eush77/remark-normalize-headings.png
-
 ## Example
 
 ```js
@@ -62,20 +56,37 @@ Modifies AST in-place.
 
 ## CLI
 
-```
+```sh
 $ remark -u remark-normalize-headings
 ```
 
 ## Related
 
--   [mdast-normalize-headings][] — [mdast][] transformation utility that is in the core of this plugin.
+*   [mdast-normalize-headings][]
+    — [mdast][] transformation utility that is in the core of this plugin.
 
 ## Install
 
-```
+```sh
 npm install remark-normalize-headings
 ```
 
 ## License
 
 MIT
+
+[remark]: https://github.com/remarkjs/remark
+
+[remark-man]: https://github.com/remarkjs/remark-man
+
+[mdast]: https://github.com/syntax-tree/mdast
+
+[mdast-normalize-headings]: https://github.com/eush77/mdast-normalize-headings
+
+[travis]: https://travis-ci.org/eush77/remark-normalize-headings
+
+[travis-badge]: https://travis-ci.org/eush77/remark-normalize-headings.svg
+
+[david]: https://david-dm.org/eush77/remark-normalize-headings
+
+[david-badge]: https://david-dm.org/eush77/remark-normalize-headings.png
diff --git a/index.js b/index.js
index 9628f5a..3394e7d 100644
--- a/index.js
+++ b/index.js
@@ -1,8 +1,7 @@
-'use strict';
+'use strict'
 
-var normalizeHeadings = require('mdast-normalize-headings');
+var normalizeHeadings = require('mdast-normalize-headings')
 
-
-module.exports = function () {
-  return normalizeHeadings;
-};
+module.exports = function() {
+  return normalizeHeadings
+}
diff --git a/package.json b/package.json
index df39b11..6b44817 100644
--- a/package.json
+++ b/package.json
@@ -28,10 +28,33 @@
     "mdast-normalize-headings": "^1.0.0"
   },
   "devDependencies": {
+    "prettier": "^1.14.2",
     "remark": "^9.0.0",
-    "tape": "^4.0.0"
+    "remark-cli": "^5.0.0",
+    "remark-preset-wooorm": "^4.0.0",
+    "tape": "^4.0.0",
+    "xo": "^0.22.0"
   },
   "scripts": {
-    "test": "tape test/*.js"
+    "format": "remark . -qfo && prettier --write \"**/*.js\" && xo --fix",
+    "test-api": "node test",
+    "test": "npm run format && npm run test-api"
+  },
+  "prettier": {
+    "tabWidth": 2,
+    "useTabs": false,
+    "singleQuote": true,
+    "bracketSpacing": false,
+    "semi": false,
+    "trailingComma": "none"
+  },
+  "xo": {
+    "prettier": true,
+    "esnext": false
+  },
+  "remarkConfig": {
+    "plugins": [
+      "preset-wooorm"
+    ]
   }
 }
diff --git a/test.js b/test.js
new file mode 100644
index 0000000..2954877
--- /dev/null
+++ b/test.js
@@ -0,0 +1,34 @@
+'use strict'
+
+var test = require('tape')
+var remark = require('remark')
+var normalizeHeadings = require('.')
+
+test('remark-normalize-headings', function(t) {
+  var parse = remark().data('settings', {position: false}).parse
+  var run = remark().use(normalizeHeadings).runSync
+
+  var input = [
+    '# One',
+    '# Two',
+    '## Level 3',
+    '### Level 4',
+    '#### Level 5',
+    '##### Level 6',
+    '###### Level 7'
+  ].join('\n\n')
+
+  var output = [
+    '# One',
+    '## Two',
+    '### Level 3',
+    '#### Level 4',
+    '##### Level 5',
+    '###### Level 6',
+    '###### Level 7'
+  ].join('\n\n')
+
+  t.deepEqual(run(parse(input)), parse(output))
+
+  t.end()
+})
diff --git a/test/hierarchy.in b/test/hierarchy.in
deleted file mode 100644
index 95aa5ff..0000000
--- a/test/hierarchy.in
+++ /dev/null
@@ -1,13 +0,0 @@
-# One
-
-# Two
-
-## Level 3
-
-### Level 4
-
-#### Level 5
-
-##### Level 6
-
-###### Level 7
diff --git a/test/hierarchy.out b/test/hierarchy.out
deleted file mode 100644
index 139b4eb..0000000
--- a/test/hierarchy.out
+++ /dev/null
@@ -1,13 +0,0 @@
-# One
-
-## Two
-
-### Level 3
-
-#### Level 4
-
-##### Level 5
-
-###### Level 6
-
-###### Level 7
diff --git a/test/test.js b/test/test.js
deleted file mode 100644
index 5cb8187..0000000
--- a/test/test.js
+++ /dev/null
@@ -1,25 +0,0 @@
-'use strict';
-
-var normalizeHeadings = require('..');
-
-var test = require('tape'),
-    remark = require('remark');
-
-var fs = require('fs'),
-    path = require('path');
-
-
-var load = function (filename) {
-  filename = path.join(__dirname, filename);
-  var markdown = fs.readFileSync(filename, { encoding: 'utf8' });
-  return remark().data('settings', { position: false }).parse(markdown);
-};
-
-
-test(function (t) {
-  var input = load('hierarchy.in');
-  var output = load('hierarchy.out');
-
-  t.deepEqual(remark().use(normalizeHeadings).runSync(input), output);
-  t.end();
-});