diff --git a/.babelrc b/.babelrc
index 7592ae4..cf3af6e 100644
--- a/.babelrc
+++ b/.babelrc
@@ -1,4 +1,17 @@
 {
-	"presets": ["es2015"],
-	"plugins": ["transform-flow-strip-types", "transform-object-rest-spread"]
+	"presets": [
+		["env", {
+			"targets": {
+				"node": "6"
+			}
+		}]
+	],
+	"plugins": [
+		["transform-runtime", {
+            "polyfill": false,
+            "regenerator": true
+        }],
+		"transform-flow-strip-types",
+		"transform-object-rest-spread"
+	]
 }
diff --git a/.flowconfig b/.flowconfig
index e69de29..0135137 100644
--- a/.flowconfig
+++ b/.flowconfig
@@ -0,0 +1,2 @@
+[ignore]
+.*/node_modules/.*
\ No newline at end of file
diff --git a/critical.css b/critical.css
deleted file mode 100644
index 9ac01ba..0000000
--- a/critical.css
+++ /dev/null
@@ -1 +0,0 @@
-.foo{color:#32cd32}.foo:before{content:"Hello, World."}
\ No newline at end of file
diff --git a/default.critical.expected.css b/default.critical.expected.css
deleted file mode 100644
index 46daac6..0000000
--- a/default.critical.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-.foo{color:#32cd32}.foo:before{content:"Hello, World."}
diff --git a/default.css b/default.css
deleted file mode 100644
index ea44c73..0000000
--- a/default.css
+++ /dev/null
@@ -1,9 +0,0 @@
-@critical;
-
-.foo {
-  color: limegreen;
-}
-
-.foo::before {
-  content: 'Hello, World.'
-}
diff --git a/default.non-critical.actual.css b/default.non-critical.actual.css
deleted file mode 100644
index b4ed413..0000000
--- a/default.non-critical.actual.css
+++ /dev/null
@@ -1,7 +0,0 @@
-.foo {
-  color: limegreen;
-}
-
-.foo::before {
-  content: 'Hello, World.'
-}
diff --git a/default.non-critical.expected.css b/default.non-critical.expected.css
deleted file mode 100644
index b4ed413..0000000
--- a/default.non-critical.expected.css
+++ /dev/null
@@ -1,7 +0,0 @@
-.foo {
-  color: limegreen;
-}
-
-.foo::before {
-  content: 'Hello, World.'
-}
diff --git a/lib/getChildRules.js b/lib/getChildRules.js
index 9667904..4134602 100644
--- a/lib/getChildRules.js
+++ b/lib/getChildRules.js
@@ -21,23 +21,23 @@ function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { de
  * @return {array} Array of child rules.
  */
 function getChildRules(css, parent) {
-  var result = [];
-  var selectorRegExp = new RegExp(parent.selector);
+  const result = [];
+  const selectorRegExp = new RegExp(parent.selector);
 
   // Walk all rules to mach child selectors
-  css.walkRules(selectorRegExp, function (rule) {
-    var childRule = (0, _matchChild.matchChild)(parent, rule);
+  css.walkRules(selectorRegExp, rule => {
+    const childRule = (0, _matchChild.matchChild)(parent, rule);
     if (childRule) {
       result.push(rule);
     }
   });
 
   // Walk all at-rules to match nested child selectors
-  css.walkAtRules(function (atRule) {
-    atRule.walkRules(selectorRegExp, function (rule) {
-      var childRule = (0, _matchChild.matchChild)(parent, rule);
+  css.walkAtRules(atRule => {
+    atRule.walkRules(selectorRegExp, rule => {
+      const childRule = (0, _matchChild.matchChild)(parent, rule);
       // Create new at-rule to append only necessary selector to critical
-      var criticalAtRule = _postcss2.default.atRule({
+      const criticalAtRule = _postcss2.default.atRule({
         name: atRule.name,
         params: atRule.params
       });
@@ -46,7 +46,7 @@ function getChildRules(css, parent) {
        * aren't identical.
        */
       if ((rule.selector === parent.selector || childRule) && _postcss2.default.parse(rule).toString() !== _postcss2.default.parse(parent).toString()) {
-        var clone = rule.clone();
+        const clone = rule.clone();
         criticalAtRule.append(clone);
         result.push(criticalAtRule);
       }
diff --git a/lib/getCriticalDestination.js b/lib/getCriticalDestination.js
index b311634..e5ad1e6 100644
--- a/lib/getCriticalDestination.js
+++ b/lib/getCriticalDestination.js
@@ -14,7 +14,7 @@ exports.getCriticalDestination = getCriticalDestination;
  * @return {string} String corresponding to output destination.
  */
 function getCriticalDestination(rule, dest) {
-  rule.walkDecls('critical-filename', function (decl) {
+  rule.walkDecls('critical-filename', decl => {
     dest = decl.value.replace(/['"]*/g, '');
     decl.remove();
   });
diff --git a/lib/getCriticalRules.js b/lib/getCriticalRules.js
index 5888ff8..75e073b 100644
--- a/lib/getCriticalRules.js
+++ b/lib/getCriticalRules.js
@@ -24,14 +24,12 @@ function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { de
  * @param {string} test Declaration string. Default  `critical-selector`
  * @return {Object} clone Cloned, cleaned root node.
  */
-function clean(root) {
-  var test = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : 'critical-selector';
-
-  var clone = root.clone();
+function clean(root, test = 'critical-selector') {
+  const clone = root.clone();
   if (clone.type === 'decl') {
     clone.remove();
   } else {
-    clone.walkDecls(test, function (decl) {
+    clone.walkDecls(test, decl => {
       decl.remove();
     });
   }
@@ -45,12 +43,12 @@ function clean(root) {
  * @return {Object} sortedRoot Root with nodes sorted by source order.
  */
 function correctSourceOrder(root) {
-  var sortedRoot = _postcss2.default.root();
-  var clone = root.clone();
-  clone.walkRules(function (rule) {
-    var start = rule.source.start.line;
+  const sortedRoot = _postcss2.default.root();
+  const clone = root.clone();
+  clone.walkRules(rule => {
+    let start = rule.source.start.line;
     if (rule.parent.type === 'atrule') {
-      var child = rule;
+      const child = rule;
       rule = _postcss2.default.atRule({
         name: rule.parent.name,
         params: rule.parent.params
@@ -91,11 +89,11 @@ function establishContainer(node) {
  * @return {Object} clonedRoot Root object.
  */
 function updateCritical(root, update) {
-  var clonedRoot = root.clone();
+  const clonedRoot = root.clone();
   if (update.type === 'rule') {
     clonedRoot.append(clean(update.clone()));
   } else {
-    update.clone().each(function (rule) {
+    update.clone().each(rule => {
       clonedRoot.append(clean(rule.root()));
     });
   }
@@ -111,21 +109,21 @@ function updateCritical(root, update) {
  * @return {object} Object containing critical rules, organized by output destination
  */
 function getCriticalRules(css, defaultDest) {
-  var critical = (0, _atRule.getCriticalFromAtRule)({ css: css, defaultDest: defaultDest });
-  css.walkDecls('critical-selector', function (decl) {
-    var parent = decl.parent,
-        value = decl.value;
-
-    var dest = (0, _getCriticalDestination.getCriticalDestination)(parent, defaultDest);
-    var container = establishContainer(parent);
-    var childRules = value === 'scope' ? (0, _getChildRules.getChildRules)(css, parent) : [];
+  const critical = (0, _atRule.getCriticalFromAtRule)({ css, defaultDest });
+  css.walkDecls('critical-selector', decl => {
+    const parent = decl.parent,
+          value = decl.value;
+
+    const dest = (0, _getCriticalDestination.getCriticalDestination)(parent, defaultDest);
+    const container = establishContainer(parent);
+    const childRules = value === 'scope' ? (0, _getChildRules.getChildRules)(css, parent) : [];
     // Sanity check, make sure we've got a root node
     critical[dest] = critical[dest] || _postcss2.default.root();
 
     switch (value) {
       case 'scope':
         // Add all child rules
-        var criticalRoot = childRules.reduce(function (acc, rule) {
+        const criticalRoot = childRules.reduce((acc, rule) => {
           return acc.append(rule.clone());
         }, critical[dest].append(container));
 
diff --git a/lib/matchChild.js b/lib/matchChild.js
index b14796d..0127059 100644
--- a/lib/matchChild.js
+++ b/lib/matchChild.js
@@ -13,6 +13,6 @@ exports.matchChild = matchChild;
  * @return {object} Parent rule for which children should be included
  */
 function matchChild(parent, rule) {
-  var childRegExp = new RegExp("(, )?(" + parent.selector + " [^,s]*),?.*"); // eslint-disable-line no-useless-escape
+  const childRegExp = new RegExp(`(, )?(${parent.selector} [^,\s]*),?.*`); // eslint-disable-line no-useless-escape
   return rule.selector !== parent.selector && rule.selector.match(childRegExp) !== null;
 }
\ No newline at end of file
diff --git a/package.json b/package.json
index 4572722..9365bcf 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "postcss-critical-css",
-  "version": "3.0.2",
+  "version": "3.0.1",
   "description": "Generate critical CSS using PostCSS",
   "main": "index.js",
   "repository": {
@@ -23,7 +23,10 @@
     "babel-eslint": "^7.2.3",
     "babel-plugin-transform-flow-strip-types": "^6.8.0",
     "babel-plugin-transform-object-rest-spread": "^6.26.0",
+    "babel-plugin-transform-runtime": "^6.23.0",
+    "babel-preset-env": "^1.7.0",
     "babel-preset-es2015": "^6.13.2",
+    "babel-runtime": "^6.26.0",
     "eslint": "^3.3.1",
     "eslint-config-standard": "^10.2.1",
     "eslint-plugin-flowtype": "^2.41.0",
@@ -32,6 +35,7 @@
     "eslint-plugin-promise": "^3.6.0",
     "eslint-plugin-standard": "^3.0.1",
     "flow-bin": "^0.48.0",
+    "jest": "^23.1.0",
     "minimist": "^1.2.0",
     "tape": "^4.8.0"
   },
@@ -41,8 +45,7 @@
     "flow": "flow; test $? -eq 0 -o $? -eq 2",
     "eslint": "eslint test/**/*.js && eslint src/**",
     "start": "eslint src/** && npm run flow && babel src --out-dir lib --watch",
-    "pretest": "./node_modules/.bin/babel-node test/preTest.js",
-    "test": "npm run build && npm run test-default && npm run test-no-preserve && npm run test-output-path && npm run test-output-dest && npm run test-no-args && npm run test-no-minify",
+    "test": "jest --verbose",
     "test-no-args": "npm run pretest -- --noArgs && tape test --noArgs --test=default",
     "test-no-minify": "npm run pretest -- --minify=false --fixtures-dir=fixtures-no-minify && tape test --fixtures-dir=fixtures-no-minify --test=default,this",
     "test-output-dest": "npm run pretest -- --outputDest='custom.css' --fixtures-dir=fixtures-output-dest && tape test --outputDest='custom.css' --fixtures-dir=fixtures-output-dest --test=default",
@@ -52,7 +55,8 @@
   },
   "dependencies": {
     "chalk": "^1.1.3",
-    "cssnano": "^4.0.0",
-    "postcss": "^7.0.0"
+    "cssnano": "^3.7.4",
+    "fs-extra": "^6.0.1",
+    "postcss": "^6.0.16"
   }
 }
diff --git a/test/atRule.spec.js b/test/atRule.spec.js
new file mode 100644
index 0000000..a2bf056
--- /dev/null
+++ b/test/atRule.spec.js
@@ -0,0 +1,29 @@
+const compareCritical = require('./compareCritical');
+const { fsTimeout, normalizeOpts } = require('./utils');
+const preTest = require('./preTest');
+
+const opts = normalizeOpts();
+beforeAll(async () => {
+  preTest('atRule', opts);
+  await fsTimeout();
+});
+
+describe('tests for @critical rule', () => {
+  it('should move all selectors in a file to critical css if @critical at-rule is used without wrapping anything', () => {
+    compareCritical(opts, 'standalone')
+  })
+
+  it('should remove @critical at-rule from non-critical css', () => {
+    compareCritical(opts, 'standalone', true)
+  })
+})
+
+describe('tests for @critical at-rule wrapping specific selectors', () => {
+  it('should move all selectors in a file to critical css if @critical rule is used without wrapping anything', () => {
+    compareCritical(opts, 'wrapping')
+  })
+
+  it('should remove @critical at-rule from non-critical css', () => {
+    compareCritical(opts, 'wrapping', true)
+  })
+})
diff --git a/test/compareCritical.js b/test/compareCritical.js
new file mode 100644
index 0000000..f474773
--- /dev/null
+++ b/test/compareCritical.js
@@ -0,0 +1,25 @@
+const fs = require('fs-extra');
+
+module.exports = function compareCritical(opts, name, testNonCritical) {
+  let basePath = opts.outputPath || `${process.cwd()}/test/fixtures`
+  let actual = opts.outputDest || 'critical.css'
+
+  if (opts.noArgs) {
+    basePath = process.cwd()
+  }
+
+  const expected = testNonCritical
+    ? `${name}.non-critical.expected.css`
+    : `${name}.critical.expected.css`
+  if (
+    (name !== 'default' || testNonCritical) &&
+    ! opts.outputDest
+  ) {
+    actual = testNonCritical
+      ? `${name}.non-critical.actual.css`
+      : `${name}.critical.actual.css`
+  }
+
+  expect(fs.readFileSync(`${basePath}/${actual}`, 'utf8').trim())
+    .toEqual(fs.readFileSync(`${basePath}/${expected}`, 'utf8').trim())
+}
diff --git a/test/default.spec.js b/test/default.spec.js
new file mode 100644
index 0000000..c03aa46
--- /dev/null
+++ b/test/default.spec.js
@@ -0,0 +1,71 @@
+const compareCritical = require('./compareCritical');
+const { fsTimeout, normalizeOpts } = require('./utils');
+const preTest = require('./preTest');
+
+describe('default tests', () => {
+  const opts = normalizeOpts();
+  beforeAll(async () => {
+    preTest('default', opts);
+    await fsTimeout();
+  });
+
+  it('should move styles into critical stylesheet if @critical at-rule is used', () => {
+    compareCritical(opts, 'default')
+  })
+
+  it('should not modify non-critical stylesheet', () => {
+    compareCritical(opts, 'default', true)
+  })
+})
+
+describe('tests for `minify` option', () => {
+  const opts = normalizeOpts({ minify: false });
+  beforeAll(async () => {
+    preTest('options', opts);
+    await fsTimeout();
+  });
+
+  it('should not minify critical CSS styles if `minify` option is set to `false`', () => {
+    compareCritical(opts, 'minify-false')
+  })
+})
+
+describe('tests for `preserve` option', () => {
+  const opts = normalizeOpts({ preserve: false });
+  beforeAll(async () => {
+    preTest('options', opts);
+    await fsTimeout();
+  });
+
+  it('should move selectors specified with `@critical` or `critical-selector` to critical css file', () => {
+    compareCritical(opts, 'preserve')
+  })
+
+  it('should remove selectors specified with `@critical` or `critical-selector` from non-critical stylesheet', () => {
+    compareCritical(opts, 'preserve', true)
+  })
+})
+
+describe('tests for `outputDest` option', () => {
+  const opts = normalizeOpts({ outputDest: 'test-output-dest.critical.actual.css' });
+  beforeAll(async () => {
+    preTest('options', opts);
+    await fsTimeout();
+  });
+
+  it('should output critical css to filename configured in `outputDest` option', () => {
+    compareCritical(opts, 'output-dest')
+  })
+})
+
+describe('tests for `outputPath` option', () => {
+  const opts = normalizeOpts({ outputPath: `${process.cwd()}/test/fixtures/options/outputPath` });
+  beforeAll(async () => {
+    preTest('options', opts);
+    await fsTimeout();
+  });
+
+  it('should output critical css to filename configured in `outputDest` option', () => {
+    compareCritical(opts, 'output-path')
+  })
+})
diff --git a/test/fixtures-no-minify/critical.css b/test/fixtures-no-minify/critical.css
deleted file mode 100644
index a7e47af..0000000
--- a/test/fixtures-no-minify/critical.css
+++ /dev/null
@@ -1,8 +0,0 @@
-
-
-.default {
-  color: orange;
-  float: left;
-  margin-right: 1em;
-  width: 100%;
-}
\ No newline at end of file
diff --git a/test/fixtures-no-minify/default.critical.expected.css b/test/fixtures-no-minify/default.critical.expected.css
deleted file mode 100644
index 1aeeec8..0000000
--- a/test/fixtures-no-minify/default.critical.expected.css
+++ /dev/null
@@ -1,8 +0,0 @@
-
-
-.default {
-  color: orange;
-  float: left;
-  margin-right: 1em;
-  width: 100%;
-}
diff --git a/test/fixtures-no-minify/this.critical.actual.css b/test/fixtures-no-minify/this.critical.actual.css
deleted file mode 100644
index f525fe0..0000000
--- a/test/fixtures-no-minify/this.critical.actual.css
+++ /dev/null
@@ -1,6 +0,0 @@
-.testing-this {
-  color: orange;
-  float: left;
-  margin-right: 1em;
-  width: 100%;
-}
\ No newline at end of file
diff --git a/test/fixtures-no-minify/this.critical.expected.css b/test/fixtures-no-minify/this.critical.expected.css
deleted file mode 100644
index e142924..0000000
--- a/test/fixtures-no-minify/this.critical.expected.css
+++ /dev/null
@@ -1,6 +0,0 @@
-.testing-this {
-  color: orange;
-  float: left;
-  margin-right: 1em;
-  width: 100%;
-}
diff --git a/test/fixtures-no-minify/this.css b/test/fixtures-no-minify/this.css
deleted file mode 100644
index e7a6cd6..0000000
--- a/test/fixtures-no-minify/this.css
+++ /dev/null
@@ -1,8 +0,0 @@
-.testing-this {
-  critical-filename: this.critical.actual.css;
-  critical-selector: this;
-  color: orange;
-  float: left;
-  margin-right: 1em;
-  width: 100%;
-}
diff --git a/test/fixtures-no-minify/this.non-critical.actual.css b/test/fixtures-no-minify/this.non-critical.actual.css
deleted file mode 100644
index e142924..0000000
--- a/test/fixtures-no-minify/this.non-critical.actual.css
+++ /dev/null
@@ -1,6 +0,0 @@
-.testing-this {
-  color: orange;
-  float: left;
-  margin-right: 1em;
-  width: 100%;
-}
diff --git a/test/fixtures-no-minify/this.non-critical.expected.css b/test/fixtures-no-minify/this.non-critical.expected.css
deleted file mode 100644
index e142924..0000000
--- a/test/fixtures-no-minify/this.non-critical.expected.css
+++ /dev/null
@@ -1,6 +0,0 @@
-.testing-this {
-  color: orange;
-  float: left;
-  margin-right: 1em;
-  width: 100%;
-}
diff --git a/test/fixtures-no-preserve/atRule-wrapping.css b/test/fixtures-no-preserve/atRule-wrapping.css
deleted file mode 100644
index 324b359..0000000
--- a/test/fixtures-no-preserve/atRule-wrapping.css
+++ /dev/null
@@ -1,11 +0,0 @@
-.foo {
-  color: gold;
-  height: 100px;
-}
-
-@critical atRule-wrapping.critical.actual.css {
-  .bar {
-    color: tomato;
-    height: 200px;
-  }
-}
diff --git a/test/fixtures-no-preserve/atRule-wrapping.non-critical.actual.css b/test/fixtures-no-preserve/atRule-wrapping.non-critical.actual.css
deleted file mode 100644
index baa5561..0000000
--- a/test/fixtures-no-preserve/atRule-wrapping.non-critical.actual.css
+++ /dev/null
@@ -1,4 +0,0 @@
-.foo {
-  color: gold;
-  height: 100px;
-}
diff --git a/test/fixtures-no-preserve/atRule-wrapping.non-critical.expected.css b/test/fixtures-no-preserve/atRule-wrapping.non-critical.expected.css
deleted file mode 100644
index baa5561..0000000
--- a/test/fixtures-no-preserve/atRule-wrapping.non-critical.expected.css
+++ /dev/null
@@ -1,4 +0,0 @@
-.foo {
-  color: gold;
-  height: 100px;
-}
diff --git a/test/fixtures-no-preserve/atRule.css b/test/fixtures-no-preserve/atRule.css
deleted file mode 100644
index d2d84e8..0000000
--- a/test/fixtures-no-preserve/atRule.css
+++ /dev/null
@@ -1,11 +0,0 @@
-@critical atRule.critical.actual.css;
-
-.foo {
-  display: flex;
-  width: calc(100% - 200px);
-}
-
-.bar {
-  border: 10px solid gold;
-  height: 100%;
-}
diff --git a/test/fixtures-no-preserve/atRule.non-critical.actual.css b/test/fixtures-no-preserve/atRule.non-critical.actual.css
deleted file mode 100644
index 8b13789..0000000
--- a/test/fixtures-no-preserve/atRule.non-critical.actual.css
+++ /dev/null
@@ -1 +0,0 @@
-
diff --git a/test/fixtures-no-preserve/atRule.non-critical.expected.css b/test/fixtures-no-preserve/atRule.non-critical.expected.css
deleted file mode 100644
index e69de29..0000000
diff --git a/test/fixtures-no-preserve/default.critical.expected.css b/test/fixtures-no-preserve/default.critical.expected.css
deleted file mode 100644
index 24dc7a1..0000000
--- a/test/fixtures-no-preserve/default.critical.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-.default{color:orange;float:left;margin-right:1em;width:100%}
\ No newline at end of file
diff --git a/test/fixtures-no-preserve/default.css b/test/fixtures-no-preserve/default.css
deleted file mode 100644
index a755513..0000000
--- a/test/fixtures-no-preserve/default.css
+++ /dev/null
@@ -1,8 +0,0 @@
-@critical;
-
-.default {
-  color: orange;
-  float: left;
-  margin-right: 1em;
-  width: 100%;
-}
diff --git a/test/fixtures-no-preserve/default.non-critical.actual.css b/test/fixtures-no-preserve/default.non-critical.actual.css
deleted file mode 100644
index 8b13789..0000000
--- a/test/fixtures-no-preserve/default.non-critical.actual.css
+++ /dev/null
@@ -1 +0,0 @@
-
diff --git a/test/fixtures-no-preserve/default.non-critical.expected.css b/test/fixtures-no-preserve/default.non-critical.expected.css
deleted file mode 100644
index e69de29..0000000
diff --git a/test/fixtures-no-preserve/media-scope.css b/test/fixtures-no-preserve/media-scope.css
deleted file mode 100644
index 103afd9..0000000
--- a/test/fixtures-no-preserve/media-scope.css
+++ /dev/null
@@ -1,10 +0,0 @@
-header.top {
-  critical-filename: media-scope.critical.actual.css;
-  critical-selector: scope;
-  background: red;
-}
-@media screen and (max-width: 400px) {
-  header.top {
-    width: 100%;
-  }
-}
diff --git a/test/fixtures-no-preserve/media-scope.non-critical.actual.css b/test/fixtures-no-preserve/media-scope.non-critical.actual.css
deleted file mode 100644
index 8b13789..0000000
--- a/test/fixtures-no-preserve/media-scope.non-critical.actual.css
+++ /dev/null
@@ -1 +0,0 @@
-
diff --git a/test/fixtures-no-preserve/media-scope.non-critical.expected.css b/test/fixtures-no-preserve/media-scope.non-critical.expected.css
deleted file mode 100644
index e69de29..0000000
diff --git a/test/fixtures-no-preserve/media-this.css b/test/fixtures-no-preserve/media-this.css
deleted file mode 100644
index a95d6ab..0000000
--- a/test/fixtures-no-preserve/media-this.css
+++ /dev/null
@@ -1,18 +0,0 @@
-@media screen and (min-width: 1024px) {
-	.foo {
-		critical-selector: this;
-    critical-filename: media-this.critical.actual.css;
-		display: flex;
-		width: calc(100% - 200px);
-	}
-
-	.bar {
-		border: 10px solid gold;
-		height: 100%;
-	}
-
-	.baz::before {
-		content: 'test';
-		position: fixed;
-	}
-}
diff --git a/test/fixtures-no-preserve/media-this.non-critical.actual.css b/test/fixtures-no-preserve/media-this.non-critical.actual.css
deleted file mode 100644
index f18683e..0000000
--- a/test/fixtures-no-preserve/media-this.non-critical.actual.css
+++ /dev/null
@@ -1,12 +0,0 @@
-@media screen and (min-width: 1024px) {
-
-	.bar {
-		border: 10px solid gold;
-		height: 100%;
-	}
-
-	.baz::before {
-		content: 'test';
-		position: fixed;
-	}
-}
diff --git a/test/fixtures-no-preserve/media-this.non-critical.expected.css b/test/fixtures-no-preserve/media-this.non-critical.expected.css
deleted file mode 100644
index f18683e..0000000
--- a/test/fixtures-no-preserve/media-this.non-critical.expected.css
+++ /dev/null
@@ -1,12 +0,0 @@
-@media screen and (min-width: 1024px) {
-
-	.bar {
-		border: 10px solid gold;
-		height: 100%;
-	}
-
-	.baz::before {
-		content: 'test';
-		position: fixed;
-	}
-}
diff --git a/test/fixtures-no-preserve/media.non-critical.actual.css b/test/fixtures-no-preserve/media.non-critical.actual.css
deleted file mode 100644
index 8b13789..0000000
--- a/test/fixtures-no-preserve/media.non-critical.actual.css
+++ /dev/null
@@ -1 +0,0 @@
-
diff --git a/test/fixtures-no-preserve/media.non-critical.expected.css b/test/fixtures-no-preserve/media.non-critical.expected.css
deleted file mode 100644
index e69de29..0000000
diff --git a/test/fixtures-no-preserve/scope.css b/test/fixtures-no-preserve/scope.css
deleted file mode 100644
index 68a87be..0000000
--- a/test/fixtures-no-preserve/scope.css
+++ /dev/null
@@ -1,9 +0,0 @@
-.foo .bar {
-  color: green;
-}
-
-.foo {
-  color: orange;
-  critical-selector: scope;
-  critical-filename: scope.critical.actual.css;
-}
diff --git a/test/fixtures-no-preserve/scope.non-critical.actual.css b/test/fixtures-no-preserve/scope.non-critical.actual.css
deleted file mode 100644
index 8b13789..0000000
--- a/test/fixtures-no-preserve/scope.non-critical.actual.css
+++ /dev/null
@@ -1 +0,0 @@
-
diff --git a/test/fixtures-no-preserve/scope.non-critical.expected.css b/test/fixtures-no-preserve/scope.non-critical.expected.css
deleted file mode 100644
index e69de29..0000000
diff --git a/test/fixtures-no-preserve/this.non-critical.actual.css b/test/fixtures-no-preserve/this.non-critical.actual.css
deleted file mode 100644
index 8b13789..0000000
--- a/test/fixtures-no-preserve/this.non-critical.actual.css
+++ /dev/null
@@ -1 +0,0 @@
-
diff --git a/test/fixtures-no-preserve/this.non-critical.expected.css b/test/fixtures-no-preserve/this.non-critical.expected.css
deleted file mode 100644
index e69de29..0000000
diff --git a/test/fixtures-output-dest/custom.css b/test/fixtures-output-dest/custom.css
deleted file mode 100644
index 24dc7a1..0000000
--- a/test/fixtures-output-dest/custom.css
+++ /dev/null
@@ -1 +0,0 @@
-.default{color:orange;float:left;margin-right:1em;width:100%}
\ No newline at end of file
diff --git a/test/fixtures-output-dest/custom.non-critical.actual.css b/test/fixtures-output-dest/custom.non-critical.actual.css
deleted file mode 100644
index 24dc7a1..0000000
--- a/test/fixtures-output-dest/custom.non-critical.actual.css
+++ /dev/null
@@ -1 +0,0 @@
-.default{color:orange;float:left;margin-right:1em;width:100%}
\ No newline at end of file
diff --git a/test/fixtures-output-dest/default.css b/test/fixtures-output-dest/default.css
deleted file mode 100644
index a755513..0000000
--- a/test/fixtures-output-dest/default.css
+++ /dev/null
@@ -1,8 +0,0 @@
-@critical;
-
-.default {
-  color: orange;
-  float: left;
-  margin-right: 1em;
-  width: 100%;
-}
diff --git a/test/fixtures-output-dest/default.non-critical.actual.css b/test/fixtures-output-dest/default.non-critical.actual.css
deleted file mode 100644
index 351a862..0000000
--- a/test/fixtures-output-dest/default.non-critical.actual.css
+++ /dev/null
@@ -1,6 +0,0 @@
-.default {
-  color: orange;
-  float: left;
-  margin-right: 1em;
-  width: 100%;
-}
diff --git a/test/fixtures-output-dest/default.non-critical.expected.css b/test/fixtures-output-dest/default.non-critical.expected.css
deleted file mode 100644
index 351a862..0000000
--- a/test/fixtures-output-dest/default.non-critical.expected.css
+++ /dev/null
@@ -1,6 +0,0 @@
-.default {
-  color: orange;
-  float: left;
-  margin-right: 1em;
-  width: 100%;
-}
diff --git a/test/fixtures-output-path/critical.css b/test/fixtures-output-path/critical.css
deleted file mode 100644
index 24dc7a1..0000000
--- a/test/fixtures-output-path/critical.css
+++ /dev/null
@@ -1 +0,0 @@
-.default{color:orange;float:left;margin-right:1em;width:100%}
\ No newline at end of file
diff --git a/test/fixtures-output-path/default.critical.expected.css b/test/fixtures-output-path/default.critical.expected.css
deleted file mode 100644
index 51c6065..0000000
--- a/test/fixtures-output-path/default.critical.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-.default{color:orange;float:left;margin-right:1em;width:100%}
diff --git a/test/fixtures-output-path/default.css b/test/fixtures-output-path/default.css
deleted file mode 100644
index a755513..0000000
--- a/test/fixtures-output-path/default.css
+++ /dev/null
@@ -1,8 +0,0 @@
-@critical;
-
-.default {
-  color: orange;
-  float: left;
-  margin-right: 1em;
-  width: 100%;
-}
diff --git a/test/fixtures-output-path/default.non-critical.actual.css b/test/fixtures-output-path/default.non-critical.actual.css
deleted file mode 100644
index 351a862..0000000
--- a/test/fixtures-output-path/default.non-critical.actual.css
+++ /dev/null
@@ -1,6 +0,0 @@
-.default {
-  color: orange;
-  float: left;
-  margin-right: 1em;
-  width: 100%;
-}
diff --git a/test/fixtures-output-path/default.non-critical.expected.css b/test/fixtures-output-path/default.non-critical.expected.css
deleted file mode 100644
index 351a862..0000000
--- a/test/fixtures-output-path/default.non-critical.expected.css
+++ /dev/null
@@ -1,6 +0,0 @@
-.default {
-  color: orange;
-  float: left;
-  margin-right: 1em;
-  width: 100%;
-}
diff --git a/test/fixtures/atRule-wrapping.critical.actual.css b/test/fixtures/atRule-wrapping.critical.actual.css
deleted file mode 100644
index 5baa7fc..0000000
--- a/test/fixtures/atRule-wrapping.critical.actual.css
+++ /dev/null
@@ -1 +0,0 @@
-.bar{color:tomato;height:200px}
\ No newline at end of file
diff --git a/test/fixtures/atRule-wrapping.critical.expected.css b/test/fixtures/atRule-wrapping.critical.expected.css
deleted file mode 100644
index 17c0170..0000000
--- a/test/fixtures/atRule-wrapping.critical.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-.bar{color:tomato;height:200px}
diff --git a/test/fixtures/atRule.critical.actual.css b/test/fixtures/atRule.critical.actual.css
deleted file mode 100644
index ef3a245..0000000
--- a/test/fixtures/atRule.critical.actual.css
+++ /dev/null
@@ -1 +0,0 @@
-.foo{display:flex;width:calc(100% - 200px)}.bar{border:10px solid gold;height:100%}
\ No newline at end of file
diff --git a/test/fixtures/atRule.expected.css b/test/fixtures/atRule.expected.css
deleted file mode 100644
index 8a820d7..0000000
--- a/test/fixtures/atRule.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-.foo{display:flex;width:calc(100% - 200px)}.bar{border:10px solid gold;height:100%}
diff --git a/test/fixtures-no-preserve/atRule.critical.actual.css b/test/fixtures/atRule/standalone.critical.actual.css
similarity index 100%
rename from test/fixtures-no-preserve/atRule.critical.actual.css
rename to test/fixtures/atRule/standalone.critical.actual.css
diff --git a/test/fixtures-no-preserve/atRule.critical.expected.css b/test/fixtures/atRule/standalone.critical.expected.css
similarity index 100%
rename from test/fixtures-no-preserve/atRule.critical.expected.css
rename to test/fixtures/atRule/standalone.critical.expected.css
diff --git a/test/fixtures/atRule.css b/test/fixtures/atRule/standalone.css
similarity index 72%
rename from test/fixtures/atRule.css
rename to test/fixtures/atRule/standalone.css
index d2d84e8..dc79bd8 100644
--- a/test/fixtures/atRule.css
+++ b/test/fixtures/atRule/standalone.css
@@ -1,4 +1,4 @@
-@critical atRule.critical.actual.css;
+@critical standalone.critical.actual.css;
 
 .foo {
   display: flex;
diff --git a/test/fixtures/atRule.critical.expected.css b/test/fixtures/atRule/standalone.expected.css
similarity index 100%
rename from test/fixtures/atRule.critical.expected.css
rename to test/fixtures/atRule/standalone.expected.css
diff --git a/test/fixtures/atRule.non-critical.actual.css b/test/fixtures/atRule/standalone.non-critical.actual.css
similarity index 100%
rename from test/fixtures/atRule.non-critical.actual.css
rename to test/fixtures/atRule/standalone.non-critical.actual.css
diff --git a/test/fixtures/atRule.non-critical.expected.css b/test/fixtures/atRule/standalone.non-critical.expected.css
similarity index 100%
rename from test/fixtures/atRule.non-critical.expected.css
rename to test/fixtures/atRule/standalone.non-critical.expected.css
diff --git a/test/fixtures-no-preserve/atRule-wrapping.critical.actual.css b/test/fixtures/atRule/wrapping.critical.actual.css
similarity index 100%
rename from test/fixtures-no-preserve/atRule-wrapping.critical.actual.css
rename to test/fixtures/atRule/wrapping.critical.actual.css
diff --git a/test/fixtures-no-preserve/atRule-wrapping.critical.expected.css b/test/fixtures/atRule/wrapping.critical.expected.css
similarity index 100%
rename from test/fixtures-no-preserve/atRule-wrapping.critical.expected.css
rename to test/fixtures/atRule/wrapping.critical.expected.css
diff --git a/test/fixtures/atRule-wrapping.css b/test/fixtures/atRule/wrapping.css
similarity index 66%
rename from test/fixtures/atRule-wrapping.css
rename to test/fixtures/atRule/wrapping.css
index 324b359..b7c9f00 100644
--- a/test/fixtures/atRule-wrapping.css
+++ b/test/fixtures/atRule/wrapping.css
@@ -3,7 +3,7 @@
   height: 100px;
 }
 
-@critical atRule-wrapping.critical.actual.css {
+@critical wrapping.critical.actual.css {
   .bar {
     color: tomato;
     height: 200px;
diff --git a/test/fixtures/atRule-wrapping.non-critical.actual.css b/test/fixtures/atRule/wrapping.non-critical.actual.css
similarity index 100%
rename from test/fixtures/atRule-wrapping.non-critical.actual.css
rename to test/fixtures/atRule/wrapping.non-critical.actual.css
diff --git a/test/fixtures/atRule-wrapping.non-critical.expected.css b/test/fixtures/atRule/wrapping.non-critical.expected.css
similarity index 100%
rename from test/fixtures/atRule-wrapping.non-critical.expected.css
rename to test/fixtures/atRule/wrapping.non-critical.expected.css
diff --git a/test/fixtures/critical.css b/test/fixtures/critical.css
deleted file mode 100644
index 24dc7a1..0000000
--- a/test/fixtures/critical.css
+++ /dev/null
@@ -1 +0,0 @@
-.default{color:orange;float:left;margin-right:1em;width:100%}
\ No newline at end of file
diff --git a/test/fixtures/default.critical.expected.css b/test/fixtures/default.critical.expected.css
deleted file mode 100644
index 51c6065..0000000
--- a/test/fixtures/default.critical.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-.default{color:orange;float:left;margin-right:1em;width:100%}
diff --git a/test/fixtures/default.css b/test/fixtures/default.css
deleted file mode 100644
index a755513..0000000
--- a/test/fixtures/default.css
+++ /dev/null
@@ -1,8 +0,0 @@
-@critical;
-
-.default {
-  color: orange;
-  float: left;
-  margin-right: 1em;
-  width: 100%;
-}
diff --git a/test/fixtures/default.non-critical.actual.css b/test/fixtures/default.non-critical.actual.css
deleted file mode 100644
index 351a862..0000000
--- a/test/fixtures/default.non-critical.actual.css
+++ /dev/null
@@ -1,6 +0,0 @@
-.default {
-  color: orange;
-  float: left;
-  margin-right: 1em;
-  width: 100%;
-}
diff --git a/test/fixtures/default.non-critical.expected.css b/test/fixtures/default.non-critical.expected.css
deleted file mode 100644
index 351a862..0000000
--- a/test/fixtures/default.non-critical.expected.css
+++ /dev/null
@@ -1,6 +0,0 @@
-.default {
-  color: orange;
-  float: left;
-  margin-right: 1em;
-  width: 100%;
-}
diff --git a/test/fixtures-no-preserve/critical.css b/test/fixtures/default/critical.css
similarity index 100%
rename from test/fixtures-no-preserve/critical.css
rename to test/fixtures/default/critical.css
diff --git a/test/fixtures-output-dest/default.critical.expected.css b/test/fixtures/default/default.critical.expected.css
similarity index 100%
rename from test/fixtures-output-dest/default.critical.expected.css
rename to test/fixtures/default/default.critical.expected.css
diff --git a/test/fixtures-no-minify/default.css b/test/fixtures/default/default.css
similarity index 100%
rename from test/fixtures-no-minify/default.css
rename to test/fixtures/default/default.css
diff --git a/test/fixtures-no-minify/default.non-critical.actual.css b/test/fixtures/default/default.non-critical.actual.css
similarity index 100%
rename from test/fixtures-no-minify/default.non-critical.actual.css
rename to test/fixtures/default/default.non-critical.actual.css
diff --git a/test/fixtures-no-minify/default.non-critical.expected.css b/test/fixtures/default/default.non-critical.expected.css
similarity index 100%
rename from test/fixtures-no-minify/default.non-critical.expected.css
rename to test/fixtures/default/default.non-critical.expected.css
diff --git a/test/fixtures/media-scope.critical.actual.css b/test/fixtures/media-scope.critical.actual.css
deleted file mode 100644
index 76b1947..0000000
--- a/test/fixtures/media-scope.critical.actual.css
+++ /dev/null
@@ -1 +0,0 @@
-header.top{background:red}@media screen and (max-width:400px){header.top{width:100%}}
\ No newline at end of file
diff --git a/test/fixtures/media-scope.critical.expected.css b/test/fixtures/media-scope.critical.expected.css
deleted file mode 100644
index 34f7882..0000000
--- a/test/fixtures/media-scope.critical.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-header.top{background:red}@media screen and (max-width:400px){header.top{width:100%}}
diff --git a/test/fixtures/media-this.critical.actual.css b/test/fixtures/media-this.critical.actual.css
deleted file mode 100644
index 2771cea..0000000
--- a/test/fixtures/media-this.critical.actual.css
+++ /dev/null
@@ -1 +0,0 @@
-@media screen and (min-width:1024px){.foo{display:flex;width:calc(100% - 200px)}}
\ No newline at end of file
diff --git a/test/fixtures/media-this.critical.expected.css b/test/fixtures/media-this.critical.expected.css
deleted file mode 100644
index cb80f92..0000000
--- a/test/fixtures/media-this.critical.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-@media screen and (min-width:1024px){.foo{display:flex;width:calc(100% - 200px)}}
diff --git a/test/fixtures/media.critical.actual.css b/test/fixtures/media.critical.actual.css
deleted file mode 100644
index 2e15cc8..0000000
--- a/test/fixtures/media.critical.actual.css
+++ /dev/null
@@ -1 +0,0 @@
-@media (min-width:700px){.foo{color:red;width:100%}}
\ No newline at end of file
diff --git a/test/fixtures/media.critical.expected.css b/test/fixtures/media.critical.expected.css
deleted file mode 100644
index 3eec687..0000000
--- a/test/fixtures/media.critical.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-@media (min-width:700px){.foo{color:red;width:100%}}
diff --git a/test/fixtures/media.css b/test/fixtures/media.css
deleted file mode 100644
index 4980df2..0000000
--- a/test/fixtures/media.css
+++ /dev/null
@@ -1,8 +0,0 @@
-@media (min-width: 700px) {
-  .foo {
-    color: red;
-    critical-selector: this;
-    width: 100%;
-    critical-filename: 'media.critical.actual.css';
-  }
-}
diff --git a/test/fixtures/options/minify-false.critical.actual.css b/test/fixtures/options/minify-false.critical.actual.css
new file mode 100644
index 0000000..30ab5f4
--- /dev/null
+++ b/test/fixtures/options/minify-false.critical.actual.css
@@ -0,0 +1 @@
+.test-minify{color:blue;font-style:italic}
\ No newline at end of file
diff --git a/test/fixtures/options/minify-false.critical.expected.css b/test/fixtures/options/minify-false.critical.expected.css
new file mode 100644
index 0000000..60f6306
--- /dev/null
+++ b/test/fixtures/options/minify-false.critical.expected.css
@@ -0,0 +1,4 @@
+.test-minify {
+	color: blue;
+	font-style: italic;
+}
diff --git a/test/fixtures/options/minify-false.css b/test/fixtures/options/minify-false.css
new file mode 100644
index 0000000..1c5e6b0
--- /dev/null
+++ b/test/fixtures/options/minify-false.css
@@ -0,0 +1,6 @@
+.test-minify {
+	color: blue;
+	critical-selector: this;
+	critical-filename: minify-false.critical.actual.css;
+	font-style: italic;
+}
diff --git a/test/fixtures/options/minify-false.non-critical.actual.css b/test/fixtures/options/minify-false.non-critical.actual.css
new file mode 100644
index 0000000..60f6306
--- /dev/null
+++ b/test/fixtures/options/minify-false.non-critical.actual.css
@@ -0,0 +1,4 @@
+.test-minify {
+	color: blue;
+	font-style: italic;
+}
diff --git a/test/fixtures/options/output-dest.critical.expected.css b/test/fixtures/options/output-dest.critical.expected.css
new file mode 100644
index 0000000..acfe5c9
--- /dev/null
+++ b/test/fixtures/options/output-dest.critical.expected.css
@@ -0,0 +1 @@
+.test-output-dest{color:blue;font-family:Times}
\ No newline at end of file
diff --git a/test/fixtures/options/output-dest.css b/test/fixtures/options/output-dest.css
new file mode 100644
index 0000000..5e2ed8c
--- /dev/null
+++ b/test/fixtures/options/output-dest.css
@@ -0,0 +1,5 @@
+.test-output-dest {
+	color: blue;
+	critical-selector: this;
+	font-family: Times;
+}
\ No newline at end of file
diff --git a/test/fixtures/options/output-dest.non-critical.actual.css b/test/fixtures/options/output-dest.non-critical.actual.css
new file mode 100644
index 0000000..3b10b3a
--- /dev/null
+++ b/test/fixtures/options/output-dest.non-critical.actual.css
@@ -0,0 +1,4 @@
+.test-output-dest {
+	color: blue;
+	font-family: Times;
+}
\ No newline at end of file
diff --git a/test/fixtures/options/output-path.critical.actual.css b/test/fixtures/options/output-path.critical.actual.css
new file mode 100644
index 0000000..5123843
--- /dev/null
+++ b/test/fixtures/options/output-path.critical.actual.css
@@ -0,0 +1 @@
+.test-output-path{color:blue;font-family:Times}
\ No newline at end of file
diff --git a/test/fixtures/options/output-path.css b/test/fixtures/options/output-path.css
new file mode 100644
index 0000000..af3037b
--- /dev/null
+++ b/test/fixtures/options/output-path.css
@@ -0,0 +1,6 @@
+.test-output-path {
+	color: blue;
+	critical-selector: this;
+	critical-filename: output-path.critical.actual.css;
+	font-family: Times;
+}
diff --git a/test/fixtures/options/output-path.non-critical.actual.css b/test/fixtures/options/output-path.non-critical.actual.css
new file mode 100644
index 0000000..14a55bd
--- /dev/null
+++ b/test/fixtures/options/output-path.non-critical.actual.css
@@ -0,0 +1,4 @@
+.test-output-path {
+	color: blue;
+	font-family: Times;
+}
diff --git a/test/fixtures/options/outputPath/output-path.critical.actual.css b/test/fixtures/options/outputPath/output-path.critical.actual.css
new file mode 100644
index 0000000..5123843
--- /dev/null
+++ b/test/fixtures/options/outputPath/output-path.critical.actual.css
@@ -0,0 +1 @@
+.test-output-path{color:blue;font-family:Times}
\ No newline at end of file
diff --git a/test/fixtures/options/outputPath/output-path.critical.expected.css b/test/fixtures/options/outputPath/output-path.critical.expected.css
new file mode 100644
index 0000000..5123843
--- /dev/null
+++ b/test/fixtures/options/outputPath/output-path.critical.expected.css
@@ -0,0 +1 @@
+.test-output-path{color:blue;font-family:Times}
\ No newline at end of file
diff --git a/test/fixtures/options/preserve.critical.actual.css b/test/fixtures/options/preserve.critical.actual.css
new file mode 100644
index 0000000..9342de8
--- /dev/null
+++ b/test/fixtures/options/preserve.critical.actual.css
@@ -0,0 +1 @@
+.another-selector{background-color:#000;color:#fff}.test-preserve{color:red;display:block}
\ No newline at end of file
diff --git a/test/fixtures/options/preserve.critical.expected.css b/test/fixtures/options/preserve.critical.expected.css
new file mode 100644
index 0000000..9342de8
--- /dev/null
+++ b/test/fixtures/options/preserve.critical.expected.css
@@ -0,0 +1 @@
+.another-selector{background-color:#000;color:#fff}.test-preserve{color:red;display:block}
\ No newline at end of file
diff --git a/test/fixtures/options/preserve.css b/test/fixtures/options/preserve.css
new file mode 100644
index 0000000..ed34a32
--- /dev/null
+++ b/test/fixtures/options/preserve.css
@@ -0,0 +1,18 @@
+.test-preserve {
+	color: red;
+	critical-selector: this;
+	critical-filename: preserve.critical.actual.css;
+	display: block;
+}
+
+@critical preserve.critical.actual.css {
+	.another-selector {
+		background-color: black;
+		color: white;
+	}
+}
+
+.this-selector-stays {
+	display: flex;
+	justify-content: center;
+}
diff --git a/test/fixtures/options/preserve.non-critical.actual.css b/test/fixtures/options/preserve.non-critical.actual.css
new file mode 100644
index 0000000..fa087d3
--- /dev/null
+++ b/test/fixtures/options/preserve.non-critical.actual.css
@@ -0,0 +1,14 @@
+.test-preserve {
+	color: red;
+	display: block;
+}
+
+.another-selector {
+		background-color: black;
+		color: white;
+	}
+
+.this-selector-stays {
+	display: flex;
+	justify-content: center;
+}
diff --git a/test/fixtures/options/preserve.non-critical.expected.css b/test/fixtures/options/preserve.non-critical.expected.css
new file mode 100644
index 0000000..812a828
--- /dev/null
+++ b/test/fixtures/options/preserve.non-critical.expected.css
@@ -0,0 +1,4 @@
+.this-selector-stays {
+	display: flex;
+	justify-content: center;
+}
diff --git a/test/fixtures/options/test-output-dest.critical.actual.css b/test/fixtures/options/test-output-dest.critical.actual.css
new file mode 100644
index 0000000..acfe5c9
--- /dev/null
+++ b/test/fixtures/options/test-output-dest.critical.actual.css
@@ -0,0 +1 @@
+.test-output-dest{color:blue;font-family:Times}
\ No newline at end of file
diff --git a/test/fixtures/scope.critical.actual.css b/test/fixtures/scope.critical.actual.css
deleted file mode 100644
index 1c02631..0000000
--- a/test/fixtures/scope.critical.actual.css
+++ /dev/null
@@ -1 +0,0 @@
-.foo .bar{color:green}.foo{color:orange}
\ No newline at end of file
diff --git a/test/fixtures/scope.critical.expected.css b/test/fixtures/scope.critical.expected.css
deleted file mode 100644
index bbba33b..0000000
--- a/test/fixtures/scope.critical.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-.foo .bar{color:green}.foo{color:orange}
diff --git a/test/fixtures-no-preserve/scope.critical.actual.css b/test/fixtures/scope/at-root.critical.actual.css
similarity index 100%
rename from test/fixtures-no-preserve/scope.critical.actual.css
rename to test/fixtures/scope/at-root.critical.actual.css
diff --git a/test/fixtures-no-preserve/scope.critical.expected.css b/test/fixtures/scope/at-root.critical.expected.css
similarity index 100%
rename from test/fixtures-no-preserve/scope.critical.expected.css
rename to test/fixtures/scope/at-root.critical.expected.css
diff --git a/test/fixtures/scope.css b/test/fixtures/scope/at-root.css
similarity index 62%
rename from test/fixtures/scope.css
rename to test/fixtures/scope/at-root.css
index 68a87be..f51492c 100644
--- a/test/fixtures/scope.css
+++ b/test/fixtures/scope/at-root.css
@@ -5,5 +5,5 @@
 .foo {
   color: orange;
   critical-selector: scope;
-  critical-filename: scope.critical.actual.css;
+  critical-filename: at-root.critical.actual.css;
 }
diff --git a/test/fixtures/scope.non-critical.actual.css b/test/fixtures/scope/at-root.non-critical.actual.css
similarity index 100%
rename from test/fixtures/scope.non-critical.actual.css
rename to test/fixtures/scope/at-root.non-critical.actual.css
diff --git a/test/fixtures/scope.non-critical.expected.css b/test/fixtures/scope/at-root.non-critical.expected.css
similarity index 100%
rename from test/fixtures/scope.non-critical.expected.css
rename to test/fixtures/scope/at-root.non-critical.expected.css
diff --git a/test/fixtures-no-preserve/media-scope.critical.actual.css b/test/fixtures/scope/media.critical.actual.css
similarity index 100%
rename from test/fixtures-no-preserve/media-scope.critical.actual.css
rename to test/fixtures/scope/media.critical.actual.css
diff --git a/test/fixtures-no-preserve/media-scope.critical.expected.css b/test/fixtures/scope/media.critical.expected.css
similarity index 100%
rename from test/fixtures-no-preserve/media-scope.critical.expected.css
rename to test/fixtures/scope/media.critical.expected.css
diff --git a/test/fixtures/media-scope.css b/test/fixtures/scope/media.css
similarity index 72%
rename from test/fixtures/media-scope.css
rename to test/fixtures/scope/media.css
index 103afd9..099cb9c 100644
--- a/test/fixtures/media-scope.css
+++ b/test/fixtures/scope/media.css
@@ -1,5 +1,5 @@
 header.top {
-  critical-filename: media-scope.critical.actual.css;
+  critical-filename: media.critical.actual.css;
   critical-selector: scope;
   background: red;
 }
diff --git a/test/fixtures/media-scope.non-critical.actual.css b/test/fixtures/scope/media.non-critical.actual.css
similarity index 100%
rename from test/fixtures/media-scope.non-critical.actual.css
rename to test/fixtures/scope/media.non-critical.actual.css
diff --git a/test/fixtures/media-scope.non-critical.expected.css b/test/fixtures/scope/media.non-critical.expected.css
similarity index 100%
rename from test/fixtures/media-scope.non-critical.expected.css
rename to test/fixtures/scope/media.non-critical.expected.css
diff --git a/test/fixtures/this.critical.actual.css b/test/fixtures/this.critical.actual.css
deleted file mode 100644
index d0f08b0..0000000
--- a/test/fixtures/this.critical.actual.css
+++ /dev/null
@@ -1 +0,0 @@
-.foo{color:red;width:100%}
\ No newline at end of file
diff --git a/test/fixtures/this.critical.expected.css b/test/fixtures/this.critical.expected.css
deleted file mode 100644
index 16e95c1..0000000
--- a/test/fixtures/this.critical.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-.foo{color:red;width:100%}
diff --git a/test/fixtures/this.css b/test/fixtures/this.css
deleted file mode 100644
index 8193c4a..0000000
--- a/test/fixtures/this.css
+++ /dev/null
@@ -1,6 +0,0 @@
-.foo {
-  color: red;
-  critical-selector: this;
-  width: 100%;
-  critical-filename: 'this.critical.actual.css';
-}
diff --git a/test/fixtures-no-preserve/this.critical.actual.css b/test/fixtures/this/at-root.critical.actual.css
similarity index 100%
rename from test/fixtures-no-preserve/this.critical.actual.css
rename to test/fixtures/this/at-root.critical.actual.css
diff --git a/test/fixtures-no-preserve/this.critical.expected.css b/test/fixtures/this/at-root.critical.expected.css
similarity index 100%
rename from test/fixtures-no-preserve/this.critical.expected.css
rename to test/fixtures/this/at-root.critical.expected.css
diff --git a/test/fixtures-no-preserve/this.css b/test/fixtures/this/at-root.css
similarity index 55%
rename from test/fixtures-no-preserve/this.css
rename to test/fixtures/this/at-root.css
index 8193c4a..6fc2438 100644
--- a/test/fixtures-no-preserve/this.css
+++ b/test/fixtures/this/at-root.css
@@ -2,5 +2,5 @@
   color: red;
   critical-selector: this;
   width: 100%;
-  critical-filename: 'this.critical.actual.css';
+  critical-filename: 'at-root.critical.actual.css';
 }
diff --git a/test/fixtures/this.non-critical.actual.css b/test/fixtures/this/at-root.non-critical.actual.css
similarity index 100%
rename from test/fixtures/this.non-critical.actual.css
rename to test/fixtures/this/at-root.non-critical.actual.css
diff --git a/test/fixtures/this.non-critical.expected.css b/test/fixtures/this/at-root.non-critical.expected.css
similarity index 100%
rename from test/fixtures/this.non-critical.expected.css
rename to test/fixtures/this/at-root.non-critical.expected.css
diff --git a/test/fixtures-no-preserve/media.critical.actual.css b/test/fixtures/this/media.critical.actual.css
similarity index 100%
rename from test/fixtures-no-preserve/media.critical.actual.css
rename to test/fixtures/this/media.critical.actual.css
diff --git a/test/fixtures-no-preserve/media.critical.expected.css b/test/fixtures/this/media.critical.expected.css
similarity index 100%
rename from test/fixtures-no-preserve/media.critical.expected.css
rename to test/fixtures/this/media.critical.expected.css
diff --git a/test/fixtures-no-preserve/media.css b/test/fixtures/this/media.css
similarity index 100%
rename from test/fixtures-no-preserve/media.css
rename to test/fixtures/this/media.css
diff --git a/test/fixtures/media.non-critical.actual.css b/test/fixtures/this/media.non-critical.actual.css
similarity index 100%
rename from test/fixtures/media.non-critical.actual.css
rename to test/fixtures/this/media.non-critical.actual.css
diff --git a/test/fixtures/media.non-critical.expected.css b/test/fixtures/this/media.non-critical.expected.css
similarity index 100%
rename from test/fixtures/media.non-critical.expected.css
rename to test/fixtures/this/media.non-critical.expected.css
diff --git a/test/fixtures-no-preserve/media-this.critical.actual.css b/test/fixtures/this/multiple.critical.actual.css
similarity index 100%
rename from test/fixtures-no-preserve/media-this.critical.actual.css
rename to test/fixtures/this/multiple.critical.actual.css
diff --git a/test/fixtures-no-preserve/media-this.critical.expected.css b/test/fixtures/this/multiple.critical.expected.css
similarity index 100%
rename from test/fixtures-no-preserve/media-this.critical.expected.css
rename to test/fixtures/this/multiple.critical.expected.css
diff --git a/test/fixtures/media-this.css b/test/fixtures/this/multiple.css
similarity index 81%
rename from test/fixtures/media-this.css
rename to test/fixtures/this/multiple.css
index a95d6ab..7a1c262 100644
--- a/test/fixtures/media-this.css
+++ b/test/fixtures/this/multiple.css
@@ -1,7 +1,7 @@
 @media screen and (min-width: 1024px) {
 	.foo {
 		critical-selector: this;
-    critical-filename: media-this.critical.actual.css;
+    	critical-filename: multiple.critical.actual.css;
 		display: flex;
 		width: calc(100% - 200px);
 	}
diff --git a/test/fixtures/media-this.non-critical.actual.css b/test/fixtures/this/multiple.non-critical.actual.css
similarity index 100%
rename from test/fixtures/media-this.non-critical.actual.css
rename to test/fixtures/this/multiple.non-critical.actual.css
diff --git a/test/fixtures/media-this.non-critical.expected.css b/test/fixtures/this/multiple.non-critical.expected.css
similarity index 100%
rename from test/fixtures/media-this.non-critical.expected.css
rename to test/fixtures/this/multiple.non-critical.expected.css
diff --git a/test/index.js b/test/index.js
deleted file mode 100644
index 8251e7a..0000000
--- a/test/index.js
+++ /dev/null
@@ -1,156 +0,0 @@
-#!/usr/bin/env node
-
-const fs = require('fs')
-const test = require('tape')
-const chalk = require('chalk')
-const cliArgs = require('minimist')(process.argv.slice(2), {
-  boolean: ['preserve'],
-  default: { preserve: true }
-})
-const fixturesDir = cliArgs['fixtures-dir'] || 'fixtures'
-let basePath = cliArgs.outputPath || `${process.cwd()}/test/${fixturesDir}`
-if (cliArgs.noArgs) {
-  basePath = process.cwd()
-}
-
-function compareCritical (t, name, testNonCritical) {
-  let actual = cliArgs.outputDest || 'critical.css'
-  const expected = testNonCritical
-    ? `${name}.non-critical.expected.css`
-    : `${name}.critical.expected.css`
-  if (name !== 'default' || testNonCritical) {
-    actual = testNonCritical
-      ? `${name}.non-critical.actual.css`
-      : `${name}.critical.actual.css`
-  }
-  console.log(`Comparing: ${expected} and ${actual}`)
-  t.equal(
-    fs.readFileSync(`${basePath}/${actual}`, 'utf8').trim(),
-    fs.readFileSync(`${basePath}/${expected}`, 'utf8').trim(),
-    `Expect ${chalk.bold(name)} should be equal to actual output`
-  )
-  t.end()
-}
-
-function initTests (key) {
-  const tests = {
-    default: () => {
-      test('Testing default critical result', t => {
-        compareCritical(t, 'default')
-      })
-
-      test('Testing default non-critical result', t => {
-        compareCritical(t, 'default', true)
-      })
-    },
-
-    this: () => {
-      test('Testing "this" critical result', t => {
-        compareCritical(t, 'this')
-      })
-
-      test('Testing "this" non-critical result', t => {
-        compareCritical(t, 'this', true)
-      })
-    },
-
-    atRule: () => {
-      test('Testing "atRule" critical result', t => {
-        compareCritical(t, 'atRule')
-      })
-
-      test('Testing "atRule" non-critical result', t => {
-        compareCritical(t, 'atRule', true)
-      })
-    },
-
-    atRuleWrapping: () => {
-      test(
-        chalk.yellow(
-          `Testing ${chalk.bold('atRule.wrapping')} critical result`
-        ),
-        t => {
-          compareCritical(t, 'atRule-wrapping')
-        }
-      )
-
-      test(
-        chalk.yellow(
-          `Testing ${chalk.bold('atRule.wrapping')} non-critical result`
-        ),
-        t => {
-          compareCritical(t, 'atRule-wrapping', true)
-        }
-      )
-    },
-
-    media: () => {
-      test('Testing "media" critical result', t => {
-        compareCritical(t, 'media')
-      })
-
-      test('Testing "media" non-critical result', t => {
-        compareCritical(t, 'media', true)
-      })
-    },
-
-    scope: () => {
-      test(
-        chalk.yellow(`Testing ${chalk.bold('scope')} critical result`),
-        t => {
-          compareCritical(t, 'scope')
-        }
-      )
-
-      test(
-        chalk.yellow(`Testing ${chalk.bold('scope')} non-critical result`),
-        t => {
-          compareCritical(t, 'scope', true)
-        }
-      )
-    },
-
-    mediaScope: () => {
-      test(
-        chalk.yellow(`Testing ${chalk.bold('media-scope')} critical result`),
-        t => {
-          compareCritical(t, 'media-scope')
-        }
-      )
-
-      test(
-        chalk.yellow(
-          `Testing ${chalk.bold('media-scope')} non-critical result`
-        ),
-        t => {
-          compareCritical(t, 'media-scope', true)
-        }
-      )
-    },
-
-    mediaThis: () => {
-      test(
-        chalk.yellow(`Testing ${chalk.bold('media-this')} critical result`),
-        t => {
-          compareCritical(t, 'media-this')
-        }
-      )
-
-      test(
-        chalk.yellow(`Testing ${chalk.bold('media-this')} non-critical result`),
-        t => {
-          compareCritical(t, 'media-this', true)
-        }
-      )
-    }
-  }
-
-  if (key) {
-    const keys = key.split(',')
-    keys.forEach(k => tests[k]())
-  } else {
-    Object.keys(tests).forEach(key => tests[key]())
-  }
-}
-
-initTests(cliArgs.test)
diff --git a/test/preTest.js b/test/preTest.js
index 4a118f2..4f3b7b6 100644
--- a/test/preTest.js
+++ b/test/preTest.js
@@ -2,89 +2,76 @@
 const fs = require('fs')
 const { bold, red } = require('chalk')
 const postcssCriticalCSS = require('..')
-const cliArgs = require('minimist')(process.argv.slice(2), {
-  boolean: ['minify', 'preserve'],
-  default: { minify: true, preserve: true }
-})
-const fixturesDir = cliArgs['fixtures-dir'] || 'fixtures'
-let basePath = cliArgs.outputPath || `${process.cwd()}/test/${fixturesDir}`
-let pluginOpts = Object.assign(
-  {},
-  {
-    minify: cliArgs.minify,
-    outputDest: cliArgs.outputDest,
-    outputPath: basePath,
-    preserve: typeof cliArgs.preserve !== 'undefined' ? cliArgs.preserve : true
-  }
-)
-if (cliArgs.noArgs) {
-  basePath = process.cwd()
-  pluginOpts = {}
-}
+const { normalizeOpts } = require('./utils');
+const postcss = require('postcss')
+
+function useFileData (data, file, opts) {
+  const pluginOpts = normalizeOpts(opts)
 
-function useFileData (data, file) {
-  postcssCriticalCSS
-    .process(data, {}, pluginOpts)
+  postcss()
+    .use(postcssCriticalCSS(pluginOpts))
+    .process(data, { from: file })
     .catch(err => {
       console.error(bold.red('Error: '), err)
       process.exit(1)
     })
-    .then(result => {
-      fs.writeFile(
-        `${basePath}/${file.split('.')[0]}.non-critical.actual.css`,
-        result.css,
-        'utf8',
-        err => {
-          if (err) {
-            throw new Error(err)
-          }
-        }
-      )
+    .then((result) => {
+      try {
+        fs.writeFileSync(
+          `${opts.outputPath}/${file.split('.')[0]}.non-critical.actual.css`,
+          result.css,
+          'utf8'
+        )
+      } catch(err) {
+        throw new Error(err)
+      }
     })
 }
 
-function deleteOldFixtures (files) {
-  let totalProcessed = 0
-  files.forEach(file => {
-    if (file.indexOf('.actual') !== -1 || file === 'critical.css') {
-      fs.unlink(`${basePath}/${file}`, err => {
-        if (err) {
-          throw new Error(err)
-        }
-        totalProcessed++
-        writeNewFixtures(totalProcessed, files)
-      })
-    } else {
-      totalProcessed++
-      writeNewFixtures(totalProcessed, files)
+function deleteOldFixtures (files, filter, opts) {
+  files.forEach((file) => {
+    if (
+      (file.includes('.actual') && file.includes(filter)) ||
+      file === 'critical.css'
+    ) {
+      try {
+        fs.unlinkSync(`${opts.outputPath}/${file}`)
+      } catch(err) {
+        throw new Error(err)
+      }
     }
   })
 }
 
-function writeNewFixtures (totalProcessed, files) {
-  if (totalProcessed !== files.length) {
-    return
-  }
-  files.forEach(file => {
+function writeNewFixtures (files, name, opts) {
+  files.forEach((file) => {
     if (
-      file.indexOf('.css') !== -1 &&
-      file.indexOf('.expected') === -1 &&
-      file.indexOf('.actual') === -1 &&
+      file.includes('.css') &&
+      ! file.includes('.expected') &&
+      ! file.includes('.actual') &&
       file !== 'critical.css'
     ) {
-      fs.readFile(`${basePath}/${file}`, 'utf8', (err, data) => {
-        if (err) {
-          throw new Error(err)
-        }
-        useFileData(data, file)
-      })
+      try {
+        const data = fs.readFileSync(`${opts.outputPath}/${file}`, 'utf8')
+        useFileData(data, file, opts)
+      } catch(err) {
+        throw new Error(err)
+      }
     }
   })
 }
 
-fs.readdir(basePath, 'utf8', (err, files) => {
-  if (err) {
+module.exports = function preTest(name, opts) {
+  opts.outputPath = opts.outputPath || `${process.cwd()}/test/fixtures/${name}`
+  if (opts.noArgs) {
+    opts.outputPath = process.cwd()
+  }
+
+  try {
+    const files = fs.readdirSync(opts.outputPath, 'utf8')
+    deleteOldFixtures(files, name, opts)
+    writeNewFixtures(files, name, opts)
+  } catch(err) {
     throw new Error(err)
   }
-  deleteOldFixtures(files)
-})
+}
diff --git a/test/scope.spec.js b/test/scope.spec.js
new file mode 100644
index 0000000..d9dc5a9
--- /dev/null
+++ b/test/scope.spec.js
@@ -0,0 +1,29 @@
+const compareCritical = require('./compareCritical');
+const { fsTimeout, normalizeOpts } = require('./utils');
+const preTest = require('./preTest');
+
+const opts = normalizeOpts();
+beforeAll(async () => {
+  preTest('scope', opts);
+  await fsTimeout();
+});
+
+describe('tests for `critical-selector: scope`', () => {
+  it('should move selectors containing `critical-selector: scope` and their children to critical css', () => {
+    compareCritical(opts, 'at-root')
+  })
+
+  it('should remove critical-selector declaration from non-critical css', () => {
+    compareCritical(opts, 'at-root', true)
+  })
+})
+
+describe('tests for selector containing `critical-selector: scope` nested under @media at-rule', () => {
+  it('should move selectors containing `critical-selector: scope` and their children to critical css, maintaing @media at-rule', () => {
+    compareCritical(opts, 'media')
+  })
+
+  it('should remove critical-selector declaration from non-critical css', () => {
+    compareCritical(opts, 'media', true)
+  })
+})
diff --git a/test/this.spec.js b/test/this.spec.js
new file mode 100644
index 0000000..3ca1f22
--- /dev/null
+++ b/test/this.spec.js
@@ -0,0 +1,39 @@
+const compareCritical = require('./compareCritical');
+const { fsTimeout, normalizeOpts } = require('./utils');
+const preTest = require('./preTest');
+
+const opts = normalizeOpts();
+beforeAll(async () => {
+  preTest('this', opts);
+  await fsTimeout();
+});
+
+describe('tests for `critical-selector: this`', () => {
+  it('should move selector to critical css if `critical-selector: this` is declared', () => {
+    compareCritical(opts, 'at-root')
+  })
+
+  it('should remove critical-selector declarations from non-critical css and leave it otherwise unmodified', () => {
+    compareCritical(opts, 'at-root', true)
+  })
+})
+
+describe('tests for a selector containing `critical-selector: this` within a @media at-rule', () => {
+  it('should move a selector within a media at-rule into critical css, maintaing @media at-rule', () => {
+    compareCritical(opts, 'media')
+  })
+
+  it('should remove critical declarations from non-critical css', () => {
+    compareCritical(opts, 'media', true)
+  })
+})
+
+describe('tests for a selector containing `critical-selector: this`, adjacent to multiple other selectors, within a @media at-rule', () => {
+  it('should move only the selector contianing `critical-selector: this` to critical CSS, maintaing @media at-rule', () => {
+    compareCritical(opts, 'multiple')
+  })
+
+  it('should remove critical declarations from non-critical css', () => {
+    compareCritical(opts, 'multiple', true)
+  })
+})
diff --git a/test/utils.js b/test/utils.js
new file mode 100644
index 0000000..221e26c
--- /dev/null
+++ b/test/utils.js
@@ -0,0 +1,16 @@
+module.exports.normalizeOpts = (opts = {}) => {
+  if (opts.noArgs) {
+    return {};
+  }
+
+  return Object.assign({
+    minify: true,
+    preserve: typeof opts.preserve !== 'undefined' ? opts.preserve : true
+  }, opts);
+}
+
+module.exports.fsTimeout = async () => {
+  return new Promise(
+    resolve => setTimeout(resolve, 250)
+  )
+}