diff --git a/.prettierignore b/.prettierignore
new file mode 100644
index 0000000..4b9e4ee
--- /dev/null
+++ b/.prettierignore
@@ -0,0 +1,3 @@
+coverage/
+remark-frontmatter.js
+remark-frontmatter.min.js
diff --git a/index.js b/index.js
index c8b9d18..3fa9ecb 100644
--- a/index.js
+++ b/index.js
@@ -1,71 +1,63 @@
-'use strict';
+'use strict'
 
-var xtend = require('xtend');
-var matters = require('./lib/matters');
-var parse = require('./lib/parse');
-var compile = require('./lib/compile');
+var xtend = require('xtend')
+var matters = require('./lib/matters')
+var parse = require('./lib/parse')
+var compile = require('./lib/compile')
 
-module.exports = frontmatter;
+module.exports = frontmatter
 
 function frontmatter(options) {
-  var parser = this.Parser;
-  var compiler = this.Compiler;
-  var config = matters(options || ['yaml']);
+  var parser = this.Parser
+  var compiler = this.Compiler
+  var config = matters(options || ['yaml'])
 
   if (isRemarkParser(parser)) {
-    attachParser(parser, config);
+    attachParser(parser, config)
   }
 
   if (isRemarkCompiler(compiler)) {
-    attachCompiler(compiler, config);
+    attachCompiler(compiler, config)
   }
 }
 
 function attachParser(parser, matters) {
-  var proto = parser.prototype;
-  var tokenizers = wrap(parse, matters);
-  var names = [];
-  var key;
+  var proto = parser.prototype
+  var tokenizers = wrap(parse, matters)
+  var names = []
+  var key
 
   for (key in tokenizers) {
-    names.push(key);
+    names.push(key)
   }
 
-  proto.blockMethods = names.concat(proto.blockMethods);
-  proto.blockTokenizers = xtend(tokenizers, proto.blockTokenizers);
+  proto.blockMethods = names.concat(proto.blockMethods)
+  proto.blockTokenizers = xtend(tokenizers, proto.blockTokenizers)
 }
 
 function attachCompiler(compiler, matters) {
-  var proto = compiler.prototype;
-  proto.visitors = xtend(wrap(compile, matters), proto.visitors);
+  var proto = compiler.prototype
+  proto.visitors = xtend(wrap(compile, matters), proto.visitors)
 }
 
 function wrap(func, matters) {
-  var result = {};
-  var length = matters.length;
-  var index = -1;
-  var tuple;
+  var result = {}
+  var length = matters.length
+  var index = -1
+  var tuple
 
   while (++index < length) {
-    tuple = func(matters[index]);
-    result[tuple[0]] = tuple[1];
+    tuple = func(matters[index])
+    result[tuple[0]] = tuple[1]
   }
 
-  return result;
+  return result
 }
 
 function isRemarkParser(parser) {
-  return Boolean(
-    parser &&
-    parser.prototype &&
-    parser.prototype.blockTokenizers
-  );
+  return Boolean(parser && parser.prototype && parser.prototype.blockTokenizers)
 }
 
 function isRemarkCompiler(compiler) {
-  return Boolean(
-    compiler &&
-    compiler.prototype &&
-    compiler.prototype.visitors
-  );
+  return Boolean(compiler && compiler.prototype && compiler.prototype.visitors)
 }
diff --git a/lib/compile.js b/lib/compile.js
index 76bc1bf..109b6ea 100644
--- a/lib/compile.js
+++ b/lib/compile.js
@@ -1,19 +1,19 @@
-'use strict';
+'use strict'
 
-var fence = require('./fence');
+var fence = require('./fence')
 
-module.exports = create;
+module.exports = create
 
 function create(matter) {
-  var type = matter.type;
-  var open = fence(matter, 'open');
-  var close = fence(matter, 'close');
+  var type = matter.type
+  var open = fence(matter, 'open')
+  var close = fence(matter, 'close')
 
-  frontmatter.displayName = type + 'FrontMatter';
+  frontmatter.displayName = type + 'FrontMatter'
 
-  return [type, frontmatter];
+  return [type, frontmatter]
 
   function frontmatter(node) {
-    return open + (node.value ? '\n' + node.value : '') + '\n' + close;
+    return open + (node.value ? '\n' + node.value : '') + '\n' + close
   }
 }
diff --git a/lib/fence.js b/lib/fence.js
index e9f367b..9e80c48 100644
--- a/lib/fence.js
+++ b/lib/fence.js
@@ -1,18 +1,18 @@
-'use strict';
+'use strict'
 
-module.exports = fence;
+module.exports = fence
 
 function fence(matter, prop) {
-  var marker;
+  var marker
 
   if (matter.marker) {
-    marker = pick(matter.marker, prop);
-    return marker + marker + marker;
+    marker = pick(matter.marker, prop)
+    return marker + marker + marker
   }
 
-  return pick(matter.fence, prop);
+  return pick(matter.fence, prop)
 }
 
 function pick(schema, prop) {
-  return typeof schema === 'string' ? schema : schema[prop];
+  return typeof schema === 'string' ? schema : schema[prop]
 }
diff --git a/lib/matters.js b/lib/matters.js
index e2da00e..df4a059 100644
--- a/lib/matters.js
+++ b/lib/matters.js
@@ -1,55 +1,55 @@
-'use strict';
+'use strict'
 
-var fault = require('fault');
+var fault = require('fault')
 
-module.exports = matters;
+module.exports = matters
 
-var own = {}.hasOwnProperty;
+var own = {}.hasOwnProperty
 
 var markers = {
   yaml: '-',
   toml: '+'
-};
+}
 
 function matters(options) {
-  var results = [];
-  var index = -1;
-  var length;
+  var results = []
+  var index = -1
+  var length
 
   /* One preset or matter. */
   if (typeof options === 'string' || !('length' in options)) {
-    options = [options];
+    options = [options]
   }
 
-  length = options.length;
+  length = options.length
 
   while (++index < length) {
-    results[index] = matter(options[index]);
+    results[index] = matter(options[index])
   }
 
-  return results;
+  return results
 }
 
 function matter(option) {
-  var result = option;
+  var result = option
 
   if (typeof result === 'string') {
     if (!own.call(markers, result)) {
-      throw fault('Missing matter definition for `%s`', result);
+      throw fault('Missing matter definition for `%s`', result)
     }
 
-    result = {type: result, marker: markers[result]};
+    result = {type: result, marker: markers[result]}
   } else if (typeof result !== 'object') {
-    throw fault('Expected matter to be an object, not `%j`', result);
+    throw fault('Expected matter to be an object, not `%j`', result)
   }
 
   if (!own.call(result, 'type')) {
-    throw fault('Missing `type` in matter `%j`', result);
+    throw fault('Missing `type` in matter `%j`', result)
   }
 
   if (!own.call(result, 'fence') && !own.call(result, 'marker')) {
-    throw fault('Missing `marker` or `fence` in matter `%j`', result);
+    throw fault('Missing `marker` or `fence` in matter `%j`', result)
   }
 
-  return result;
+  return result
 }
diff --git a/lib/parse.js b/lib/parse.js
index d431727..a78b36f 100644
--- a/lib/parse.js
+++ b/lib/parse.js
@@ -1,45 +1,45 @@
-'use strict';
+'use strict'
 
-var fence = require('./fence');
+var fence = require('./fence')
 
-module.exports = create;
+module.exports = create
 
 function create(matter) {
-  var name = matter.type + 'FrontMatter';
-  var open = fence(matter, 'open');
-  var close = fence(matter, 'close');
-  var newline = '\n';
+  var name = matter.type + 'FrontMatter'
+  var open = fence(matter, 'open')
+  var close = fence(matter, 'close')
+  var newline = '\n'
 
-  frontmatter.displayName = name;
-  frontmatter.onlyAtStart = true;
+  frontmatter.displayName = name
+  frontmatter.onlyAtStart = true
 
-  return [name, frontmatter];
+  return [name, frontmatter]
 
   function frontmatter(eat, value, silent) {
-    var index = open.length;
-    var offset;
+    var index = open.length
+    var offset
 
     if (value.slice(0, index) !== open || value.charAt(index) !== newline) {
-      return;
+      return
     }
 
-    offset = value.indexOf(close, index);
+    offset = value.indexOf(close, index)
 
     while (offset !== -1 && value.charAt(offset - 1) !== newline) {
-      index = offset + close.length;
-      offset = value.indexOf(close, index);
+      index = offset + close.length
+      offset = value.indexOf(close, index)
     }
 
     if (offset !== -1) {
       /* istanbul ignore if - never used (yet) */
       if (silent) {
-        return true;
+        return true
       }
 
       return eat(value.slice(0, offset + close.length))({
         type: matter.type,
         value: value.slice(open.length + 1, offset - 1)
-      });
+      })
     }
   }
 }
diff --git a/package.json b/package.json
index 85d7c56..85ade56 100644
--- a/package.json
+++ b/package.json
@@ -30,6 +30,7 @@
     "is-hidden": "^1.1.0",
     "not": "^0.1.0",
     "nyc": "^12.0.0",
+    "prettier": "^1.14.2",
     "remark": "^9.0.0",
     "remark-cli": "^5.0.0",
     "remark-preset-wooorm": "^4.0.0",
@@ -40,14 +41,13 @@
     "xo": "^0.22.0"
   },
   "scripts": {
-    "build-md": "remark *.md -qfo",
+    "format": "remark *.md -qfo && prettier --write \"**/*.js\" && xo --fix",
     "build-bundle": "browserify . -s remarkFrontmatter > remark-frontmatter.js",
     "build-mangle": "browserify . -s remarkFrontmatter -p tinyify > remark-frontmatter.min.js",
-    "build": "npm run build-md && npm run build-bundle && npm run build-mangle",
-    "lint": "xo",
+    "build": "npm run build-bundle && npm run build-mangle",
     "test-api": "node test",
     "test-coverage": "nyc --reporter lcov tape test/index.js",
-    "test": "npm run build && npm run lint && npm run test-coverage"
+    "test": "npm run format && npm run build && npm run test-coverage"
   },
   "nyc": {
     "check-coverage": true,
@@ -55,8 +55,16 @@
     "functions": 100,
     "branches": 100
   },
+  "prettier": {
+    "tabWidth": 2,
+    "useTabs": false,
+    "singleQuote": true,
+    "bracketSpacing": false,
+    "semi": false,
+    "trailingComma": "none"
+  },
   "xo": {
-    "space": true,
+    "prettier": true,
     "esnext": false,
     "rules": {
       "guard-for-in": "off"
diff --git a/readme.md b/readme.md
index cfa1705..560306f 100644
--- a/readme.md
+++ b/readme.md
@@ -25,25 +25,25 @@ title = "New Website"
 And our script, `example.js`, looks as follows:
 
 ```javascript
-var vfile = require('to-vfile');
-var report = require('vfile-reporter');
-var unified = require('unified');
-var parse = require('remark-parse');
-var stringify = require('remark-stringify');
-var frontmatter = require('remark-frontmatter');
+var vfile = require('to-vfile')
+var report = require('vfile-reporter')
+var unified = require('unified')
+var parse = require('remark-parse')
+var stringify = require('remark-stringify')
+var frontmatter = require('remark-frontmatter')
 
 unified()
   .use(parse)
   .use(stringify)
   .use(frontmatter, ['yaml', 'toml'])
   .use(logger)
-  .process(vfile.readSync('example.md'), function (err, file) {
-    console.log(String(file));
-    console.error(report(err || file));
-  });
+  .process(vfile.readSync('example.md'), function(err, file) {
+    console.log(String(file))
+    console.error(report(err || file))
+  })
 
 function logger() {
-  return console.dir;
+  return console.dir
 }
 ```
 
diff --git a/test/index.js b/test/index.js
index bee1900..ce2f273 100644
--- a/test/index.js
+++ b/test/index.js
@@ -1,115 +1,121 @@
-'use strict';
-
-var fs = require('fs');
-var path = require('path');
-var test = require('tape');
-var vfile = require('to-vfile');
-var unified = require('unified');
-var remark = require('remark');
-var not = require('not');
-var hidden = require('is-hidden');
-var frontmatter = require('..');
-
-var join = path.join;
-var read = fs.readFileSync;
-var write = fs.writeFileSync;
-var dir = fs.readdirSync;
-
-test('frontmatter()', function (t) {
-  t.equal(typeof frontmatter, 'function', 'should be a function');
-
-  t.doesNotThrow(
-    function () {
-      remark().use(frontmatter).freeze();
-    },
-    'should not throw if not passed options'
-  );
-
-  t.doesNotThrow(
-    function () {
-      unified().use(frontmatter).freeze();
-    },
-    'should not throw if without parser or compiler'
-  );
+'use strict'
+
+var fs = require('fs')
+var path = require('path')
+var test = require('tape')
+var vfile = require('to-vfile')
+var unified = require('unified')
+var remark = require('remark')
+var not = require('not')
+var hidden = require('is-hidden')
+var frontmatter = require('..')
+
+var join = path.join
+var read = fs.readFileSync
+var write = fs.writeFileSync
+var dir = fs.readdirSync
+
+test('frontmatter()', function(t) {
+  t.equal(typeof frontmatter, 'function', 'should be a function')
+
+  t.doesNotThrow(function() {
+    remark()
+      .use(frontmatter)
+      .freeze()
+  }, 'should not throw if not passed options')
+
+  t.doesNotThrow(function() {
+    unified()
+      .use(frontmatter)
+      .freeze()
+  }, 'should not throw if without parser or compiler')
 
   t.throws(
-    function () {
-      unified().use(frontmatter, [1]).freeze();
+    function() {
+      unified()
+        .use(frontmatter, [1])
+        .freeze()
     },
     /^Error: Expected matter to be an object, not `1`/,
     'should throw if not given a preset or a matter'
-  );
+  )
 
   t.throws(
-    function () {
-      unified().use(frontmatter, ['jsonml']).freeze();
+    function() {
+      unified()
+        .use(frontmatter, ['jsonml'])
+        .freeze()
     },
     /^Error: Missing matter definition for `jsonml`/,
     'should throw if given an unknown preset'
-  );
+  )
 
   t.throws(
-    function () {
-      unified().use(frontmatter, [{marker: '*'}]).freeze();
+    function() {
+      unified()
+        .use(frontmatter, [{marker: '*'}])
+        .freeze()
     },
     /^Error: Missing `type` in matter `{"marker":"\*"}`/,
     'should throw if given a matter without `type`'
-  );
+  )
 
   t.throws(
-    function () {
-      unified().use(frontmatter, [{type: 'jsonml'}]).freeze();
+    function() {
+      unified()
+        .use(frontmatter, [{type: 'jsonml'}])
+        .freeze()
     },
     /^Error: Missing `marker` or `fence` in matter `{"type":"jsonml"}`/,
     'should throw if given a matter without `marker`'
-  );
+  )
 
-  t.end();
-});
+  t.end()
+})
 
-test('fixtures', function (t) {
-  var base = join(__dirname, 'fixtures');
-  var entries = dir(base).filter(not(hidden));
+test('fixtures', function(t) {
+  var base = join(__dirname, 'fixtures')
+  var entries = dir(base).filter(not(hidden))
 
-  t.plan(entries.length);
+  t.plan(entries.length)
 
-  entries.forEach(each);
+  entries.forEach(each)
 
   function each(fixture) {
-    t.test(fixture, function (st) {
-      var input = vfile.readSync(join(base, fixture, 'input.md'));
-      var treePath = join(base, fixture, 'tree.json');
-      var outputPath = join(base, fixture, 'output.md');
-      var output;
-      var actual;
-      var expected;
-      var config;
-      var proc;
+    t.test(fixture, function(st) {
+      var input = vfile.readSync(join(base, fixture, 'input.md'))
+      var treePath = join(base, fixture, 'tree.json')
+      var outputPath = join(base, fixture, 'output.md')
+      var output
+      var actual
+      var expected
+      var config
+      var proc
 
       try {
-        config = JSON.parse(read(join(base, fixture, 'config.json')));
+        config = JSON.parse(read(join(base, fixture, 'config.json')))
       } catch (err) {}
 
-      proc = remark().use(frontmatter, config);
-      actual = proc.parse(input);
+      proc = remark().use(frontmatter, config)
+      actual = proc.parse(input)
 
       try {
-        output = read(outputPath, 'utf8');
+        output = read(outputPath, 'utf8')
       } catch (err) {
-        output = String(input);
+        output = String(input)
       }
 
       try {
-        expected = JSON.parse(read(treePath));
+        expected = JSON.parse(read(treePath))
       } catch (err) {
         /* New fixture. */
-        write(treePath, JSON.stringify(actual, 0, 2) + '\n');
-        expected = actual;
+        write(treePath, JSON.stringify(actual, 0, 2) + '\n')
+        expected = actual
       }
 
-      st.deepEqual(actual, expected, 'tree');
-      st.equal(String(proc.processSync(input)), output, 'process');
-      st.end();
-    });
+      st.deepEqual(actual, expected, 'tree')
+      st.equal(String(proc.processSync(input)), output, 'process')
+      st.end()
+    })
   }
-});
+})