diff --git a/.eslintignore b/.eslintignore
index ca1cfe1eb05..5053ed53c34 100644
--- a/.eslintignore
+++ b/.eslintignore
@@ -14,3 +14,4 @@ dist
 
 coverage
 node_modules
+tmp
diff --git a/.gitignore b/.gitignore
index 23af83c4273..830d7a4cac7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -15,3 +15,4 @@ logs
 npm-debug.log*
 yarn-debug.log*
 yarn-error.log*
+tmp
diff --git a/.prettierignore b/.prettierignore
index 6aac09c05e5..bc04c907c1f 100644
--- a/.prettierignore
+++ b/.prettierignore
@@ -2,3 +2,4 @@ packages/core/parcel-bundler/src/builtins
 packages/core/parcel-bundler/test/integration
 packages/core/parcel-bundler/test/input
 packages/core/parcel-bundler/test/dist
+tmp
diff --git a/packages/core/fs/.gitignore b/packages/core/fs/.gitignore
new file mode 100644
index 00000000000..a65b41774ad
--- /dev/null
+++ b/packages/core/fs/.gitignore
@@ -0,0 +1 @@
+lib
diff --git a/packages/core/fs/index.js b/packages/core/fs/index.js
new file mode 100644
index 00000000000..d5bd6981bc3
--- /dev/null
+++ b/packages/core/fs/index.js
@@ -0,0 +1,5 @@
+// Node 8 supports native async functions - no need to use compiled code!
+module.exports =
+  parseInt(process.versions.node, 10) < 8
+    ? require('./lib/fs')
+    : require('./src/fs');
diff --git a/packages/core/fs/package.json b/packages/core/fs/package.json
new file mode 100644
index 00000000000..a457e82e649
--- /dev/null
+++ b/packages/core/fs/package.json
@@ -0,0 +1,26 @@
+{
+  "name": "@parcel/fs",
+  "version": "1.10.3",
+  "description": "Blazing fast, zero configuration web application bundler",
+  "main": "index.js",
+  "license": "MIT",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/parcel-bundler/parcel.git"
+  },
+  "engines": {
+    "node": ">= 6.0.0"
+  },
+  "scripts": {
+    "test": "echo this package has no tests yet",
+    "test-ci": "yarn build && yarn test",
+    "format": "prettier --write \"./{src,bin,test}/**/*.{js,json,md}\"",
+    "lint": "eslint . && prettier \"./{src,bin,test}/**/*.{js,json,md}\" --list-different",
+    "build": "babel src -d lib",
+    "prepublish": "yarn build"
+  },
+  "dependencies": {
+    "mkdirp": "^0.5.1",
+    "@parcel/utils": "^1.10.3"
+  }
+}
diff --git a/packages/core/fs/src/.babelrc b/packages/core/fs/src/.babelrc
new file mode 100644
index 00000000000..1968e060259
--- /dev/null
+++ b/packages/core/fs/src/.babelrc
@@ -0,0 +1,8 @@
+{
+  "presets": [["@babel/preset-env", {
+    "targets": {
+      "node": "6"
+    }
+  }]],
+  "plugins": ["@babel/plugin-transform-runtime"]
+}
diff --git a/packages/core/fs/src/.eslintrc.json b/packages/core/fs/src/.eslintrc.json
new file mode 100644
index 00000000000..387cf114abe
--- /dev/null
+++ b/packages/core/fs/src/.eslintrc.json
@@ -0,0 +1,3 @@
+{
+  "extends": "../../../../.eslintrc.json"
+}
diff --git a/packages/core/parcel-bundler/src/utils/fs.js b/packages/core/fs/src/fs.js
similarity index 93%
rename from packages/core/parcel-bundler/src/utils/fs.js
rename to packages/core/fs/src/fs.js
index 830efa410aa..2677726507a 100644
--- a/packages/core/parcel-bundler/src/utils/fs.js
+++ b/packages/core/fs/src/fs.js
@@ -1,4 +1,4 @@
-const promisify = require('./promisify');
+const {promisify} = require('@parcel/utils');
 const fs = require('fs');
 const mkdirp = require('mkdirp');
 
diff --git a/packages/core/logger/package.json b/packages/core/logger/package.json
index dd781655fba..d7146e6111f 100644
--- a/packages/core/logger/package.json
+++ b/packages/core/logger/package.json
@@ -21,7 +21,8 @@
   },
   "devDependencies": {
     "mocha": "^5.2.0",
-    "sinon": "^5.0.1"
+    "sinon": "^5.0.1",
+    "@parcel/babel-register": "^1.10.3"
   },
   "dependencies": {
     "chalk": "^2.1.0",
diff --git a/packages/core/parcel-bundler/.gitignore b/packages/core/parcel-bundler/.gitignore
index 98e260578c0..bc45e23288c 100644
--- a/packages/core/parcel-bundler/.gitignore
+++ b/packages/core/parcel-bundler/.gitignore
@@ -8,3 +8,4 @@ test/integration/**/Cargo.lock
 test/**/node_modules
 test/**/yarn.lock
 test/**/package-lock.json
+test/integration/babel-plugin-autoinstall/package.json
\ No newline at end of file
diff --git a/packages/core/parcel-bundler/package.json b/packages/core/parcel-bundler/package.json
index ec5c7ba84c3..20f9140b887 100644
--- a/packages/core/parcel-bundler/package.json
+++ b/packages/core/parcel-bundler/package.json
@@ -70,7 +70,9 @@
     "ws": "^5.1.1",
     "@parcel/watcher": "1.10.3",
     "@parcel/workers": "^1.10.3",
-    "@parcel/logger": "^1.10.3"
+    "@parcel/logger": "^1.10.3",
+    "@parcel/utils": "^1.10.3",
+    "@parcel/fs": "^1.10.3"
   },
   "devDependencies": {
     "@babel/cli": "^7.0.0",
@@ -114,7 +116,8 @@
     "typescript": "^3.0.0",
     "vue": "^2.5.16",
     "vue-template-compiler": "^2.5.16",
-    "@parcel/babel-register": "^1.10.3"
+    "@parcel/babel-register": "^1.10.3",
+    "@parcel/test-utils": "^1.10.3"
   },
   "scripts": {
     "test": "cross-env NODE_ENV=test mocha",
diff --git a/packages/core/parcel-bundler/src/Asset.js b/packages/core/parcel-bundler/src/Asset.js
index 1a68aa377f1..3b3c11a7668 100644
--- a/packages/core/parcel-bundler/src/Asset.js
+++ b/packages/core/parcel-bundler/src/Asset.js
@@ -1,7 +1,7 @@
 const URL = require('url');
 const path = require('path');
 const clone = require('clone');
-const fs = require('./utils/fs');
+const fs = require('@parcel/fs');
 const md5 = require('./utils/md5');
 const isURL = require('./utils/is-url');
 const config = require('./utils/config');
diff --git a/packages/core/parcel-bundler/src/Bundler.js b/packages/core/parcel-bundler/src/Bundler.js
index d577f4654fe..f82222bf88f 100644
--- a/packages/core/parcel-bundler/src/Bundler.js
+++ b/packages/core/parcel-bundler/src/Bundler.js
@@ -1,4 +1,4 @@
-const fs = require('./utils/fs');
+const fs = require('@parcel/fs');
 const Resolver = require('./Resolver');
 const Parser = require('./Parser');
 const WorkerFarm = require('@parcel/workers');
diff --git a/packages/core/parcel-bundler/src/FSCache.js b/packages/core/parcel-bundler/src/FSCache.js
index ff683ef4fd4..dedee45b2ea 100644
--- a/packages/core/parcel-bundler/src/FSCache.js
+++ b/packages/core/parcel-bundler/src/FSCache.js
@@ -1,4 +1,4 @@
-const fs = require('./utils/fs');
+const fs = require('@parcel/fs');
 const path = require('path');
 const md5 = require('./utils/md5');
 const objectHash = require('./utils/objectHash');
diff --git a/packages/core/parcel-bundler/src/Resolver.js b/packages/core/parcel-bundler/src/Resolver.js
index d6de2c32bbe..d5037782eaa 100755
--- a/packages/core/parcel-bundler/src/Resolver.js
+++ b/packages/core/parcel-bundler/src/Resolver.js
@@ -2,7 +2,7 @@ const builtins = require('./builtins');
 const nodeBuiltins = require('node-libs-browser');
 const path = require('path');
 const {isGlob} = require('./utils/glob');
-const fs = require('./utils/fs');
+const fs = require('@parcel/fs');
 const micromatch = require('micromatch');
 
 const EMPTY_SHIM = require.resolve('./builtins/_empty');
diff --git a/packages/core/parcel-bundler/src/assets/GLSLAsset.js b/packages/core/parcel-bundler/src/assets/GLSLAsset.js
index dee790d8191..fc69a96cf88 100644
--- a/packages/core/parcel-bundler/src/assets/GLSLAsset.js
+++ b/packages/core/parcel-bundler/src/assets/GLSLAsset.js
@@ -1,7 +1,7 @@
 const Asset = require('../Asset');
 const localRequire = require('../utils/localRequire');
 const path = require('path');
-const promisify = require('../utils/promisify');
+const {promisify} = require('@parcel/utils');
 const Resolver = require('../Resolver');
 
 class GLSLAsset extends Asset {
diff --git a/packages/core/parcel-bundler/src/assets/GraphqlAsset.js b/packages/core/parcel-bundler/src/assets/GraphqlAsset.js
index 8517e2574f3..c03bea63f42 100644
--- a/packages/core/parcel-bundler/src/assets/GraphqlAsset.js
+++ b/packages/core/parcel-bundler/src/assets/GraphqlAsset.js
@@ -1,7 +1,7 @@
 const Asset = require('../Asset');
 const localRequire = require('../utils/localRequire');
 const Resolver = require('../Resolver');
-const fs = require('../utils/fs');
+const fs = require('@parcel/fs');
 const os = require('os');
 
 const IMPORT_RE = /^# *import +['"](.*)['"] *;? *$/;
diff --git a/packages/core/parcel-bundler/src/assets/JSAsset.js b/packages/core/parcel-bundler/src/assets/JSAsset.js
index ef758511b6e..5e108895203 100644
--- a/packages/core/parcel-bundler/src/assets/JSAsset.js
+++ b/packages/core/parcel-bundler/src/assets/JSAsset.js
@@ -14,7 +14,7 @@ const terser = require('../transforms/terser');
 const SourceMap = require('../SourceMap');
 const hoist = require('../scope-hoisting/hoist');
 const path = require('path');
-const fs = require('../utils/fs');
+const fs = require('@parcel/fs');
 const logger = require('@parcel/logger');
 
 const IMPORT_RE = /\b(?:import\b|export\b|require\s*\()/;
diff --git a/packages/core/parcel-bundler/src/assets/LESSAsset.js b/packages/core/parcel-bundler/src/assets/LESSAsset.js
index aa4241edf24..f9784899809 100644
--- a/packages/core/parcel-bundler/src/assets/LESSAsset.js
+++ b/packages/core/parcel-bundler/src/assets/LESSAsset.js
@@ -1,8 +1,8 @@
 const Asset = require('../Asset');
 const localRequire = require('../utils/localRequire');
-const promisify = require('../utils/promisify');
+const {promisify} = require('@parcel/utils');
 const Resolver = require('../Resolver');
-const fs = require('../utils/fs');
+const fs = require('@parcel/fs');
 const path = require('path');
 const parseCSSImport = require('../utils/parseCSSImport');
 
diff --git a/packages/core/parcel-bundler/src/assets/ReasonAsset.js b/packages/core/parcel-bundler/src/assets/ReasonAsset.js
index 5d5509fa6bd..1c195457c3b 100644
--- a/packages/core/parcel-bundler/src/assets/ReasonAsset.js
+++ b/packages/core/parcel-bundler/src/assets/ReasonAsset.js
@@ -1,5 +1,5 @@
 const Asset = require('../Asset');
-const fs = require('../utils/fs');
+const fs = require('@parcel/fs');
 const localRequire = require('../utils/localRequire');
 
 class ReasonAsset extends Asset {
diff --git a/packages/core/parcel-bundler/src/assets/RustAsset.js b/packages/core/parcel-bundler/src/assets/RustAsset.js
index 2c6cfb690f3..cb73ac93e1c 100644
--- a/packages/core/parcel-bundler/src/assets/RustAsset.js
+++ b/packages/core/parcel-bundler/src/assets/RustAsset.js
@@ -1,10 +1,10 @@
 const path = require('path');
 const commandExists = require('command-exists');
 const childProcess = require('child_process');
-const promisify = require('../utils/promisify');
+const {promisify} = require('@parcel/utils');
 const exec = promisify(childProcess.execFile);
 const tomlify = require('tomlify-j0.4');
-const fs = require('../utils/fs');
+const fs = require('@parcel/fs');
 const Asset = require('../Asset');
 const config = require('../utils/config');
 const pipeSpawn = require('../utils/pipeSpawn');
diff --git a/packages/core/parcel-bundler/src/assets/SASSAsset.js b/packages/core/parcel-bundler/src/assets/SASSAsset.js
index b62524bcd96..3760328e650 100644
--- a/packages/core/parcel-bundler/src/assets/SASSAsset.js
+++ b/packages/core/parcel-bundler/src/assets/SASSAsset.js
@@ -1,6 +1,6 @@
 const Asset = require('../Asset');
 const localRequire = require('../utils/localRequire');
-const promisify = require('../utils/promisify');
+const {promisify} = require('@parcel/utils');
 const path = require('path');
 const os = require('os');
 const Resolver = require('../Resolver');
diff --git a/packages/core/parcel-bundler/src/assets/StylusAsset.js b/packages/core/parcel-bundler/src/assets/StylusAsset.js
index 114fc0e293f..b32946380c7 100644
--- a/packages/core/parcel-bundler/src/assets/StylusAsset.js
+++ b/packages/core/parcel-bundler/src/assets/StylusAsset.js
@@ -2,7 +2,7 @@
 const Asset = require('../Asset');
 const localRequire = require('../utils/localRequire');
 const Resolver = require('../Resolver');
-const fs = require('../utils/fs');
+const fs = require('@parcel/fs');
 const {dirname, resolve, relative} = require('path');
 const {isGlob, glob} = require('../utils/glob');
 
diff --git a/packages/core/parcel-bundler/src/packagers/Packager.js b/packages/core/parcel-bundler/src/packagers/Packager.js
index c60dfb7fd4a..ab5f9fbfb09 100644
--- a/packages/core/parcel-bundler/src/packagers/Packager.js
+++ b/packages/core/parcel-bundler/src/packagers/Packager.js
@@ -1,7 +1,7 @@
 const fs = require('fs');
-const promisify = require('../utils/promisify');
+const {promisify} = require('@parcel/utils');
 const path = require('path');
-const {mkdirp} = require('../utils/fs');
+const {mkdirp} = require('@parcel/fs');
 
 class Packager {
   constructor(bundle, bundler) {
diff --git a/packages/core/parcel-bundler/src/packagers/RawPackager.js b/packages/core/parcel-bundler/src/packagers/RawPackager.js
index 06677f38b04..90f1701c6b7 100644
--- a/packages/core/parcel-bundler/src/packagers/RawPackager.js
+++ b/packages/core/parcel-bundler/src/packagers/RawPackager.js
@@ -1,6 +1,6 @@
 const Packager = require('./Packager');
 const path = require('path');
-const fs = require('../utils/fs');
+const fs = require('@parcel/fs');
 
 class RawPackager extends Packager {
   static shouldAddAsset() {
diff --git a/packages/core/parcel-bundler/src/transforms/babel/babelrc.js b/packages/core/parcel-bundler/src/transforms/babel/babelrc.js
index a7e44ebec20..f5a67aac31c 100644
--- a/packages/core/parcel-bundler/src/transforms/babel/babelrc.js
+++ b/packages/core/parcel-bundler/src/transforms/babel/babelrc.js
@@ -3,7 +3,7 @@ const logger = require('@parcel/logger');
 const path = require('path');
 const localRequire = require('../../utils/localRequire');
 const installPackage = require('../../utils/installPackage');
-const fs = require('../../utils/fs');
+const fs = require('@parcel/fs');
 const micromatch = require('micromatch');
 
 async function getBabelConfig(asset, isSource) {
diff --git a/packages/core/parcel-bundler/src/transforms/babel/config.js b/packages/core/parcel-bundler/src/transforms/babel/config.js
index abffc73bc80..cc48de65fdb 100644
--- a/packages/core/parcel-bundler/src/transforms/babel/config.js
+++ b/packages/core/parcel-bundler/src/transforms/babel/config.js
@@ -3,7 +3,7 @@ const getEnvConfig = require('./env');
 const getJSXConfig = require('./jsx');
 const getFlowConfig = require('./flow');
 const path = require('path');
-const fs = require('../../utils/fs');
+const fs = require('@parcel/fs');
 
 const NODE_MODULES = `${path.sep}node_modules${path.sep}`;
 const ENV_PLUGINS = require('@babel/preset-env/data/plugins');
diff --git a/packages/core/parcel-bundler/src/utils/config.js b/packages/core/parcel-bundler/src/utils/config.js
index 7fd06af210d..56633d3cb6f 100644
--- a/packages/core/parcel-bundler/src/utils/config.js
+++ b/packages/core/parcel-bundler/src/utils/config.js
@@ -1,4 +1,4 @@
-const fs = require('./fs');
+const fs = require('@parcel/fs');
 const path = require('path');
 const clone = require('clone');
 
diff --git a/packages/core/parcel-bundler/src/utils/getCertificate.js b/packages/core/parcel-bundler/src/utils/getCertificate.js
index 43d3afec6b2..91552aacc56 100644
--- a/packages/core/parcel-bundler/src/utils/getCertificate.js
+++ b/packages/core/parcel-bundler/src/utils/getCertificate.js
@@ -1,4 +1,4 @@
-const fs = require('./fs');
+const fs = require('@parcel/fs');
 
 async function getCertificate(options) {
   try {
diff --git a/packages/core/parcel-bundler/src/utils/installPackage.js b/packages/core/parcel-bundler/src/utils/installPackage.js
index 4748ccd784e..fee03bcb207 100644
--- a/packages/core/parcel-bundler/src/utils/installPackage.js
+++ b/packages/core/parcel-bundler/src/utils/installPackage.js
@@ -1,12 +1,12 @@
 const config = require('./config');
-const promisify = require('./promisify');
+const {promisify} = require('@parcel/utils');
 const resolve = promisify(require('resolve'));
 const commandExists = require('command-exists');
 const logger = require('@parcel/logger');
 const pipeSpawn = require('./pipeSpawn');
 const PromiseQueue = require('./PromiseQueue');
 const path = require('path');
-const fs = require('./fs');
+const fs = require('@parcel/fs');
 const WorkerFarm = require('@parcel/workers');
 
 const YARN_LOCK = 'yarn.lock';
diff --git a/packages/core/parcel-bundler/src/utils/localRequire.js b/packages/core/parcel-bundler/src/utils/localRequire.js
index a34e6e84c57..24f20da9345 100644
--- a/packages/core/parcel-bundler/src/utils/localRequire.js
+++ b/packages/core/parcel-bundler/src/utils/localRequire.js
@@ -1,5 +1,5 @@
 const {dirname} = require('path');
-const promisify = require('../utils/promisify');
+const {promisify} = require('@parcel/utils');
 const resolve = promisify(require('resolve'));
 const installPackage = require('./installPackage');
 
diff --git a/packages/core/parcel-bundler/test/asset.js b/packages/core/parcel-bundler/test/asset.js
index 5992bf3b740..11f83118cba 100644
--- a/packages/core/parcel-bundler/test/asset.js
+++ b/packages/core/parcel-bundler/test/asset.js
@@ -1,5 +1,5 @@
 const assert = require('assert');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const path = require('path');
 const Asset = require('../src/Asset');
 const {bundle} = require('./utils');
diff --git a/packages/core/parcel-bundler/test/autoinstall.js b/packages/core/parcel-bundler/test/autoinstall.js
index 86cb8e90a54..0aa5b8fb098 100644
--- a/packages/core/parcel-bundler/test/autoinstall.js
+++ b/packages/core/parcel-bundler/test/autoinstall.js
@@ -1,6 +1,6 @@
 const assert = require('assert');
 const install = require('../src/utils/installPackage');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const {ncp, rimraf} = require('./utils');
 const path = require('path');
 const inputDirPath = path.join(__dirname, '/input');
diff --git a/packages/core/parcel-bundler/test/babel.js b/packages/core/parcel-bundler/test/babel.js
index 8ebedb1d75a..5383d61392e 100644
--- a/packages/core/parcel-bundler/test/babel.js
+++ b/packages/core/parcel-bundler/test/babel.js
@@ -1,5 +1,5 @@
 const babelCore = require('@babel/core');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const {
   babel6toBabel7,
   babel7toBabel6
diff --git a/packages/core/parcel-bundler/test/contentHashing.js b/packages/core/parcel-bundler/test/contentHashing.js
index b230e44556b..9dc279db394 100644
--- a/packages/core/parcel-bundler/test/contentHashing.js
+++ b/packages/core/parcel-bundler/test/contentHashing.js
@@ -1,6 +1,6 @@
 const assert = require('assert');
 const path = require('path');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const {bundle, rimraf, ncp} = require('./utils');
 
 describe('content hashing', function() {
diff --git a/packages/core/parcel-bundler/test/css.js b/packages/core/parcel-bundler/test/css.js
index feeba213645..44be2354224 100644
--- a/packages/core/parcel-bundler/test/css.js
+++ b/packages/core/parcel-bundler/test/css.js
@@ -1,6 +1,6 @@
 const assert = require('assert');
 const path = require('path');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const {bundle, run, assertBundleTree, rimraf, ncp} = require('./utils');
 
 describe('css', function() {
diff --git a/packages/core/parcel-bundler/test/elm.js b/packages/core/parcel-bundler/test/elm.js
index 245ac4ca46c..31174c29615 100644
--- a/packages/core/parcel-bundler/test/elm.js
+++ b/packages/core/parcel-bundler/test/elm.js
@@ -1,5 +1,5 @@
 const assert = require('assert');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const {bundle, assertBundleTree, run} = require('./utils');
 
 describe('elm', function() {
diff --git a/packages/core/parcel-bundler/test/encodedURI.js b/packages/core/parcel-bundler/test/encodedURI.js
index bcaee2be22e..8450f167962 100644
--- a/packages/core/parcel-bundler/test/encodedURI.js
+++ b/packages/core/parcel-bundler/test/encodedURI.js
@@ -1,6 +1,6 @@
 const assert = require('assert');
 const path = require('path');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const {bundle, assertBundleTree} = require('./utils');
 
 describe('encodedURI', function() {
diff --git a/packages/core/parcel-bundler/test/fs-cache.js b/packages/core/parcel-bundler/test/fs-cache.js
index feb1734eb32..f868ce894fa 100644
--- a/packages/core/parcel-bundler/test/fs-cache.js
+++ b/packages/core/parcel-bundler/test/fs-cache.js
@@ -1,7 +1,8 @@
 const assert = require('assert');
 const path = require('path');
-const fs = require('../src/utils/fs');
-const {sleep, rimraf, ncp} = require('./utils');
+const fs = require('@parcel/fs');
+const {rimraf, ncp} = require('./utils');
+const {sleep} = require('@parcel/test-utils');
 const FSCache = require('../src/FSCache');
 
 const cachePath = path.join(__dirname, '.cache');
diff --git a/packages/core/parcel-bundler/test/fs.js b/packages/core/parcel-bundler/test/fs.js
index c3640d988e1..1bfa96c2721 100644
--- a/packages/core/parcel-bundler/test/fs.js
+++ b/packages/core/parcel-bundler/test/fs.js
@@ -1,5 +1,5 @@
 const assert = require('assert');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const path = require('path');
 const {bundle, run, assertBundleTree} = require('./utils');
 
diff --git a/packages/core/parcel-bundler/test/generateCertificate.js b/packages/core/parcel-bundler/test/generateCertificate.js
index ede0d1d1179..844156eb7a0 100644
--- a/packages/core/parcel-bundler/test/generateCertificate.js
+++ b/packages/core/parcel-bundler/test/generateCertificate.js
@@ -1,6 +1,6 @@
 const assert = require('assert');
 const path = require('path');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const generateCertificate = require('../src/utils/generateCertificate');
 const {rimraf, ncp} = require('./utils');
 
diff --git a/packages/core/parcel-bundler/test/getCertificate.js b/packages/core/parcel-bundler/test/getCertificate.js
index 841e4be378c..67a1b99f7f2 100644
--- a/packages/core/parcel-bundler/test/getCertificate.js
+++ b/packages/core/parcel-bundler/test/getCertificate.js
@@ -1,6 +1,6 @@
 const assert = require('assert');
 const path = require('path');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const getCertificate = require('../src/utils/getCertificate');
 
 const https = {
diff --git a/packages/core/parcel-bundler/test/glob.js b/packages/core/parcel-bundler/test/glob.js
index f63268010bd..9663d7be4b6 100644
--- a/packages/core/parcel-bundler/test/glob.js
+++ b/packages/core/parcel-bundler/test/glob.js
@@ -1,5 +1,5 @@
 const assert = require('assert');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const path = require('path');
 const {bundle, run, assertBundleTree} = require('./utils');
 
diff --git a/packages/core/parcel-bundler/test/glsl.js b/packages/core/parcel-bundler/test/glsl.js
index f28f67e5cfb..b8b1db9e3db 100644
--- a/packages/core/parcel-bundler/test/glsl.js
+++ b/packages/core/parcel-bundler/test/glsl.js
@@ -1,6 +1,6 @@
 const assert = require('assert');
 const path = require('path');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const {bundle, run, assertBundleTree, normaliseNewlines} = require('./utils');
 
 describe('glsl', function() {
diff --git a/packages/core/parcel-bundler/test/hmr.js b/packages/core/parcel-bundler/test/hmr.js
index a7b0fee1f68..e06276c6e30 100644
--- a/packages/core/parcel-bundler/test/hmr.js
+++ b/packages/core/parcel-bundler/test/hmr.js
@@ -1,7 +1,8 @@
 const assert = require('assert');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const path = require('path');
-const {bundler, run, sleep, rimraf, ncp} = require('./utils');
+const {bundler, run, rimraf, ncp} = require('./utils');
+const {sleep} = require('@parcel/test-utils');
 const WebSocket = require('ws');
 const json5 = require('json5');
 const sinon = require('sinon');
diff --git a/packages/core/parcel-bundler/test/html.js b/packages/core/parcel-bundler/test/html.js
index aba09e19e87..b5574abf088 100644
--- a/packages/core/parcel-bundler/test/html.js
+++ b/packages/core/parcel-bundler/test/html.js
@@ -1,5 +1,5 @@
 const assert = require('assert');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const {bundle, assertBundleTree} = require('./utils');
 const path = require('path');
 
diff --git a/packages/core/parcel-bundler/test/javascript.js b/packages/core/parcel-bundler/test/javascript.js
index a19a6a31f13..afb7605b934 100644
--- a/packages/core/parcel-bundler/test/javascript.js
+++ b/packages/core/parcel-bundler/test/javascript.js
@@ -1,5 +1,5 @@
 const assert = require('assert');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const path = require('path');
 const {
   bundle,
@@ -9,7 +9,7 @@ const {
   deferred,
   ncp
 } = require('./utils');
-const {mkdirp} = require('../src/utils/fs');
+const {mkdirp} = require('@parcel/fs');
 const {symlinkSync} = require('fs');
 
 describe('javascript', function() {
diff --git a/packages/core/parcel-bundler/test/less.js b/packages/core/parcel-bundler/test/less.js
index 01d9c880504..da522dd66d0 100644
--- a/packages/core/parcel-bundler/test/less.js
+++ b/packages/core/parcel-bundler/test/less.js
@@ -1,6 +1,6 @@
 const assert = require('assert');
 const path = require('path');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const {bundle, run, assertBundleTree} = require('./utils');
 
 describe('less', function() {
diff --git a/packages/core/parcel-bundler/test/lineCounter.js b/packages/core/parcel-bundler/test/lineCounter.js
index 1fb8a37be0c..e74c65ee15d 100644
--- a/packages/core/parcel-bundler/test/lineCounter.js
+++ b/packages/core/parcel-bundler/test/lineCounter.js
@@ -1,4 +1,4 @@
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const assert = require('assert');
 const lineCounter = require('../src/utils/lineCounter');
 
diff --git a/packages/core/parcel-bundler/test/parser.js b/packages/core/parcel-bundler/test/parser.js
index 0b82acfa26b..af10583255a 100644
--- a/packages/core/parcel-bundler/test/parser.js
+++ b/packages/core/parcel-bundler/test/parser.js
@@ -1,6 +1,6 @@
 const assert = require('assert');
 const path = require('path');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const {bundle, assertBundleTree} = require('./utils');
 
 describe('parser', function() {
diff --git a/packages/core/parcel-bundler/test/pug.js b/packages/core/parcel-bundler/test/pug.js
index c35ebcddd7e..79bc8f0f778 100644
--- a/packages/core/parcel-bundler/test/pug.js
+++ b/packages/core/parcel-bundler/test/pug.js
@@ -1,6 +1,6 @@
 const assert = require('assert');
 const path = require('path');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const {bundle, assertBundleTree, normaliseNewlines} = require('./utils');
 
 describe('pug', function() {
diff --git a/packages/core/parcel-bundler/test/resolver.js b/packages/core/parcel-bundler/test/resolver.js
index 9c8259d0a2a..f645f23dd8d 100644
--- a/packages/core/parcel-bundler/test/resolver.js
+++ b/packages/core/parcel-bundler/test/resolver.js
@@ -2,7 +2,7 @@ const Resolver = require('../src/Resolver');
 const path = require('path');
 const assert = require('assert');
 const {rimraf, ncp} = require('./utils');
-const {mkdirp} = require('../src/utils/fs');
+const {mkdirp} = require('@parcel/fs');
 const {symlinkSync} = require('fs');
 
 const rootDir = path.join(__dirname, 'input/resolver');
diff --git a/packages/core/parcel-bundler/test/rust.js b/packages/core/parcel-bundler/test/rust.js
index a6935b04c54..90e4bd11b60 100644
--- a/packages/core/parcel-bundler/test/rust.js
+++ b/packages/core/parcel-bundler/test/rust.js
@@ -1,7 +1,7 @@
 const assert = require('assert');
 const path = require('path');
 const {bundle, bundler, run, assertBundleTree} = require('./utils');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const commandExists = require('command-exists');
 
 describe('rust', function() {
diff --git a/packages/core/parcel-bundler/test/sass.js b/packages/core/parcel-bundler/test/sass.js
index fdcafa2c7fd..5febcbd0e64 100644
--- a/packages/core/parcel-bundler/test/sass.js
+++ b/packages/core/parcel-bundler/test/sass.js
@@ -1,6 +1,6 @@
 const assert = require('assert');
 const path = require('path');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const {bundle, run, assertBundleTree} = require('./utils');
 
 describe('sass', function() {
diff --git a/packages/core/parcel-bundler/test/scope-hoisting.js b/packages/core/parcel-bundler/test/scope-hoisting.js
index 65dd8a71f55..f54d6949763 100644
--- a/packages/core/parcel-bundler/test/scope-hoisting.js
+++ b/packages/core/parcel-bundler/test/scope-hoisting.js
@@ -1,7 +1,7 @@
 const assert = require('assert');
 const path = require('path');
 const {bundle: _bundle, run} = require('./utils');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 
 const bundle = (name, opts = {}) =>
   _bundle(name, Object.assign({scopeHoist: true}, opts));
diff --git a/packages/core/parcel-bundler/test/server.js b/packages/core/parcel-bundler/test/server.js
index cff34af0164..a00cd6c4816 100644
--- a/packages/core/parcel-bundler/test/server.js
+++ b/packages/core/parcel-bundler/test/server.js
@@ -1,6 +1,6 @@
 const assert = require('assert');
 const path = require('path');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const {bundler} = require('./utils');
 const http = require('http');
 const https = require('https');
diff --git a/packages/core/parcel-bundler/test/sourcemaps.js b/packages/core/parcel-bundler/test/sourcemaps.js
index 598343a52ce..4eafe6b6e05 100644
--- a/packages/core/parcel-bundler/test/sourcemaps.js
+++ b/packages/core/parcel-bundler/test/sourcemaps.js
@@ -1,5 +1,5 @@
 const assert = require('assert');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const path = require('path');
 const mapValidator = require('sourcemap-validator');
 const {bundler, bundle, run, assertBundleTree} = require('./utils');
diff --git a/packages/core/parcel-bundler/test/stylus.js b/packages/core/parcel-bundler/test/stylus.js
index 3704be344dc..40458ed46ed 100644
--- a/packages/core/parcel-bundler/test/stylus.js
+++ b/packages/core/parcel-bundler/test/stylus.js
@@ -1,6 +1,6 @@
 const assert = require('assert');
 const path = require('path');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const {bundle, run, assertBundleTree} = require('./utils');
 
 describe('stylus', function() {
diff --git a/packages/core/parcel-bundler/test/sugarss.js b/packages/core/parcel-bundler/test/sugarss.js
index bf83487f41d..6f0e18994df 100644
--- a/packages/core/parcel-bundler/test/sugarss.js
+++ b/packages/core/parcel-bundler/test/sugarss.js
@@ -1,6 +1,6 @@
 const assert = require('assert');
 const {bundle, assertBundleTree} = require('./utils');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const path = require('path');
 
 describe('sugarss', function() {
diff --git a/packages/core/parcel-bundler/test/typescript.js b/packages/core/parcel-bundler/test/typescript.js
index 2d07dd607fb..7aaada0a37b 100644
--- a/packages/core/parcel-bundler/test/typescript.js
+++ b/packages/core/parcel-bundler/test/typescript.js
@@ -1,6 +1,6 @@
 const assert = require('assert');
 const path = require('path');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const {bundle, run, assertBundleTree} = require('./utils');
 
 describe('typescript', function() {
diff --git a/packages/core/parcel-bundler/test/utils.js b/packages/core/parcel-bundler/test/utils.js
index c7681c4ec5a..f844538007c 100644
--- a/packages/core/parcel-bundler/test/utils.js
+++ b/packages/core/parcel-bundler/test/utils.js
@@ -1,13 +1,14 @@
 const Bundler = require('../src/Bundler');
 const assert = require('assert');
 const vm = require('vm');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const nodeFS = require('fs');
 const path = require('path');
 const WebSocket = require('ws');
 const Module = require('module');
 
-const promisify = require('../src/utils/promisify');
+const {promisify} = require('@parcel/utils');
+const {sleep} = require('@parcel/test-utils');
 const rimraf = promisify(require('rimraf'));
 const ncp = promisify(require('ncp'));
 
@@ -38,10 +39,6 @@ beforeEach(async function() {
   await removeDistDirectory();
 });
 
-function sleep(ms) {
-  return new Promise(resolve => setTimeout(resolve, ms));
-}
-
 function bundler(file, opts) {
   return new Bundler(
     file,
@@ -275,7 +272,6 @@ function normaliseNewlines(text) {
   return text.replace(/(\r\n|\n|\r)/g, '\n');
 }
 
-exports.sleep = sleep;
 exports.bundler = bundler;
 exports.bundle = bundle;
 exports.run = run;
diff --git a/packages/core/parcel-bundler/test/vue.js b/packages/core/parcel-bundler/test/vue.js
index 8e19930f8e5..c53dbb5220f 100644
--- a/packages/core/parcel-bundler/test/vue.js
+++ b/packages/core/parcel-bundler/test/vue.js
@@ -1,7 +1,7 @@
 const assert = require('assert');
 const path = require('path');
 const {bundle, assertBundleTree, run} = require('./utils');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 
 describe('vue', function() {
   it('should produce a basic vue bundle', async function() {
diff --git a/packages/core/parcel-bundler/test/watcher.js b/packages/core/parcel-bundler/test/watcher.js
index 87607512784..58bee8fb362 100644
--- a/packages/core/parcel-bundler/test/watcher.js
+++ b/packages/core/parcel-bundler/test/watcher.js
@@ -1,16 +1,16 @@
 const assert = require('assert');
-const fs = require('../src/utils/fs');
+const fs = require('@parcel/fs');
 const nodeFS = require('fs');
 const path = require('path');
 const {
   bundler,
   run,
   assertBundleTree,
-  sleep,
   nextBundle,
   rimraf,
   ncp
 } = require('./utils');
+const {sleep} = require('@parcel/test-utils');
 const {symlinkSync} = require('fs');
 
 const inputDir = path.join(__dirname, '/input');
diff --git a/packages/core/test-utils/.gitignore b/packages/core/test-utils/.gitignore
new file mode 100644
index 00000000000..a65b41774ad
--- /dev/null
+++ b/packages/core/test-utils/.gitignore
@@ -0,0 +1 @@
+lib
diff --git a/packages/core/test-utils/index.js b/packages/core/test-utils/index.js
new file mode 100644
index 00000000000..e879acea0a2
--- /dev/null
+++ b/packages/core/test-utils/index.js
@@ -0,0 +1,5 @@
+// Node 8 supports native async functions - no need to use compiled code!
+module.exports =
+  parseInt(process.versions.node, 10) < 8
+    ? require('./lib/utils')
+    : require('./src/utils');
diff --git a/packages/core/test-utils/package.json b/packages/core/test-utils/package.json
new file mode 100644
index 00000000000..023b4b997c0
--- /dev/null
+++ b/packages/core/test-utils/package.json
@@ -0,0 +1,22 @@
+{
+  "name": "@parcel/test-utils",
+  "version": "1.10.3",
+  "description": "Blazing fast, zero configuration web application bundler",
+  "main": "index.js",
+  "license": "MIT",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/parcel-bundler/parcel.git"
+  },
+  "engines": {
+    "node": ">= 6.0.0"
+  },
+  "scripts": {
+    "test": "echo this package has no tests yet",
+    "test-ci": "yarn build && yarn test",
+    "format": "prettier --write \"./{src,bin,test}/**/*.{js,json,md}\"",
+    "lint": "eslint . && prettier \"./{src,bin,test}/**/*.{js,json,md}\" --list-different",
+    "build": "babel src -d lib",
+    "prepublish": "yarn build"
+  }
+}
diff --git a/packages/core/test-utils/src/.babelrc b/packages/core/test-utils/src/.babelrc
new file mode 100644
index 00000000000..1968e060259
--- /dev/null
+++ b/packages/core/test-utils/src/.babelrc
@@ -0,0 +1,8 @@
+{
+  "presets": [["@babel/preset-env", {
+    "targets": {
+      "node": "6"
+    }
+  }]],
+  "plugins": ["@babel/plugin-transform-runtime"]
+}
diff --git a/packages/core/test-utils/src/.eslintrc.json b/packages/core/test-utils/src/.eslintrc.json
new file mode 100644
index 00000000000..387cf114abe
--- /dev/null
+++ b/packages/core/test-utils/src/.eslintrc.json
@@ -0,0 +1,3 @@
+{
+  "extends": "../../../../.eslintrc.json"
+}
diff --git a/packages/core/test-utils/src/utils.js b/packages/core/test-utils/src/utils.js
new file mode 100644
index 00000000000..4cdf552655a
--- /dev/null
+++ b/packages/core/test-utils/src/utils.js
@@ -0,0 +1,5 @@
+function sleep(ms) {
+  return new Promise(resolve => setTimeout(resolve, ms));
+}
+
+exports.sleep = sleep;
diff --git a/packages/core/utils/.gitignore b/packages/core/utils/.gitignore
new file mode 100644
index 00000000000..a65b41774ad
--- /dev/null
+++ b/packages/core/utils/.gitignore
@@ -0,0 +1 @@
+lib
diff --git a/packages/core/utils/index.js b/packages/core/utils/index.js
new file mode 100644
index 00000000000..86e3b5c897a
--- /dev/null
+++ b/packages/core/utils/index.js
@@ -0,0 +1,10 @@
+// Node 8 supports native async functions - no need to use compiled code!
+exports.promisify =
+  parseInt(process.versions.node, 10) < 8
+    ? require('./lib/promisify')
+    : require('./src/promisify');
+
+exports.errorUtils =
+  parseInt(process.versions.node, 10) < 8
+    ? require('./lib/errorUtils')
+    : require('./src/errorUtils');
diff --git a/packages/core/utils/package.json b/packages/core/utils/package.json
new file mode 100644
index 00000000000..988a8f50732
--- /dev/null
+++ b/packages/core/utils/package.json
@@ -0,0 +1,22 @@
+{
+  "name": "@parcel/utils",
+  "version": "1.10.3",
+  "description": "Blazing fast, zero configuration web application bundler",
+  "main": "index.js",
+  "license": "MIT",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/parcel-bundler/parcel.git"
+  },
+  "engines": {
+    "node": ">= 6.0.0"
+  },
+  "scripts": {
+    "test": "echo this package has no tests yet",
+    "test-ci": "yarn build && yarn test",
+    "format": "prettier --write \"./{src,bin,test}/**/*.{js,json,md}\"",
+    "lint": "eslint . && prettier \"./{src,bin,test}/**/*.{js,json,md}\" --list-different",
+    "build": "babel src -d lib",
+    "prepublish": "yarn build"
+  }
+}
diff --git a/packages/core/utils/src/.babelrc b/packages/core/utils/src/.babelrc
new file mode 100644
index 00000000000..1968e060259
--- /dev/null
+++ b/packages/core/utils/src/.babelrc
@@ -0,0 +1,8 @@
+{
+  "presets": [["@babel/preset-env", {
+    "targets": {
+      "node": "6"
+    }
+  }]],
+  "plugins": ["@babel/plugin-transform-runtime"]
+}
diff --git a/packages/core/utils/src/.eslintrc.json b/packages/core/utils/src/.eslintrc.json
new file mode 100644
index 00000000000..387cf114abe
--- /dev/null
+++ b/packages/core/utils/src/.eslintrc.json
@@ -0,0 +1,3 @@
+{
+  "extends": "../../../../.eslintrc.json"
+}
diff --git a/packages/core/workers/src/errorUtils.js b/packages/core/utils/src/errorUtils.js
similarity index 100%
rename from packages/core/workers/src/errorUtils.js
rename to packages/core/utils/src/errorUtils.js
diff --git a/packages/core/parcel-bundler/src/utils/promisify.js b/packages/core/utils/src/promisify.js
similarity index 100%
rename from packages/core/parcel-bundler/src/utils/promisify.js
rename to packages/core/utils/src/promisify.js
diff --git a/packages/core/watcher/package.json b/packages/core/watcher/package.json
index 1646fc08799..19656404b63 100644
--- a/packages/core/watcher/package.json
+++ b/packages/core/watcher/package.json
@@ -9,10 +9,21 @@
     "url": "https://github.com/parcel-bundler/parcel.git"
   },
   "scripts": {
+    "test": "cross-env NODE_ENV=test mocha",
+    "test-ci": "yarn build && yarn test",
+    "format": "prettier --write \"./{src,bin,test}/**/*.{js,json,md}\"",
+    "lint": "eslint . && prettier \"./{src,bin,test}/**/*.{js,json,md}\" --list-different",
     "build": "babel src -d lib",
     "prepublish": "yarn build"
   },
   "dependencies": {
     "fswatcher-child": "^1.0.5"
+  },
+  "devDependencies": {
+    "mocha": "^5.2.0",
+    "@parcel/babel-register": "^1.10.3",
+    "@parcel/fs": "^1.10.3",
+    "@parcel/utils": "^1.10.3",
+    "@parcel/test-utils": "^1.10.3"
   }
 }
diff --git a/packages/core/watcher/src/Watcher.js b/packages/core/watcher/src/Watcher.js
index a7b7fc67ce9..dccd5cf3292 100644
--- a/packages/core/watcher/src/Watcher.js
+++ b/packages/core/watcher/src/Watcher.js
@@ -1,5 +1,8 @@
-const FSWatcher = require('fswatcher-child');
+const fork = require('child_process').fork;
+const optionsTransfer = require('./options');
 const Path = require('path');
+const {EventEmitter} = require('events');
+const {errorUtils} = require('@parcel/utils');
 
 /**
  * This watcher wraps chokidar so that we watch directories rather than individual files on macOS.
@@ -7,21 +10,152 @@ const Path = require('path');
  * Chokidar does not have support for watching directories on non-macOS platforms, so we disable
  * this behavior in order to prevent watching more individual files than necessary (e.g. node_modules).
  */
-class Watcher {
-  constructor() {
-    // FS events on macOS are flakey in the tests, which write lots of files very quickly
-    // See https://github.com/paulmillr/chokidar/issues/612
-    this.shouldWatchDirs =
-      process.platform === 'darwin' && process.env.NODE_ENV !== 'test';
-    this.watcher = new FSWatcher({
-      useFsEvents: this.shouldWatchDirs,
+class Watcher extends EventEmitter {
+  constructor(
+    options = {
+      // FS events on macOS are flakey in the tests, which write lots of files very quickly
+      // See https://github.com/paulmillr/chokidar/issues/612
+      useFsEvents:
+        process.platform === 'darwin' && process.env.NODE_ENV !== 'test',
       ignoreInitial: true,
       ignorePermissionErrors: true,
       ignored: /\.cache|\.git/
-    });
-
+    }
+  ) {
+    super();
+    this.options = optionsTransfer.encode(options);
+    this.watchedPaths = new Set();
+    this.child = null;
+    this.ready = false;
+    this.readyQueue = [];
     this.watchedDirectories = new Map();
     this.stopped = false;
+
+    this.on('ready', () => {
+      this.ready = true;
+      for (let func of this.readyQueue) {
+        func();
+      }
+      this.readyQueue = [];
+    });
+
+    this.startchild();
+  }
+
+  startchild() {
+    if (this.child) return;
+
+    let filteredArgs = process.execArgv.filter(
+      v => !/^--(debug|inspect)/.test(v)
+    );
+
+    let options = {
+      execArgv: filteredArgs,
+      env: process.env,
+      cwd: process.cwd()
+    };
+
+    this.child = fork(Path.join(__dirname, 'child'), process.argv, options);
+
+    if (this.watchedPaths.size > 0) {
+      this.sendCommand('add', [Array.from(this.watchedPaths)]);
+    }
+
+    this.child.send({
+      type: 'init',
+      options: this.options
+    });
+
+    this.child.on('message', msg => this.handleEmit(msg.event, msg.path));
+    this.child.on('error', () => {});
+    this.child.on('exit', () => this.handleClosed());
+    // this.child.on('close', () => this.handleClosed());
+  }
+
+  handleClosed() {
+    if (!this.stopped) {
+      // Restart the child
+      this.child = null;
+      this.ready = false;
+      this.startchild();
+    }
+
+    this.emit('childDead');
+  }
+
+  handleEmit(event, data) {
+    if (event === 'watcherError') {
+      data = errorUtils.jsonToError(data);
+    }
+
+    this.emit(event, data);
+  }
+
+  sendCommand(func, args) {
+    if (!this.ready) {
+      return this.readyQueue.push(() => this.sendCommand(func, args));
+    }
+
+    this.child.send({
+      type: 'function',
+      name: func,
+      args: args
+    });
+  }
+
+  _addPath(path) {
+    if (!this.watchedPaths.has(path)) {
+      this.watchedPaths.add(path);
+      return true;
+    }
+  }
+
+  add(paths) {
+    let added = false;
+    if (Array.isArray(paths)) {
+      for (let path of paths) {
+        added = !added ? this._addPath(path) : true;
+      }
+    } else {
+      added = this._addPath(paths);
+    }
+    if (added) this.sendCommand('add', [paths]);
+  }
+
+  _closePath(path) {
+    if (this.watchedPaths.has(path)) {
+      this.watchedPaths.delete(path);
+    }
+    this.sendCommand('_closePath', [path]);
+  }
+
+  _emulateChildDead() {
+    if (!this.child) {
+      return;
+    }
+
+    this.child.send({
+      type: 'die'
+    });
+  }
+
+  _emulateChildError() {
+    if (!this.child) {
+      return;
+    }
+
+    this.child.send({
+      type: 'emulate_error'
+    });
+  }
+
+  getWatched() {
+    let watchList = {};
+    for (let path of this.watchedPaths) {
+      let key = this.options.cwd ? Path.relative(this.options.cwd, path) : path;
+      watchList[key || '.'] = [];
+    }
+    return watchList;
   }
 
   /**
@@ -72,12 +206,12 @@ class Watcher {
 
         for (let dir of children) {
           count += this.watchedDirectories.get(dir);
-          this.watcher._closePath(dir);
+          this._closePath(dir);
           this.watchedDirectories.delete(dir);
         }
 
         let dir = Path.dirname(path);
-        this.watcher.add(dir);
+        this.add(dir);
         this.watchedDirectories.set(dir, count);
       } else {
         // Otherwise, increment the reference count of the parent watcher.
@@ -87,10 +221,22 @@ class Watcher {
         );
       }
     } else {
-      this.watcher.add(path);
+      this.add(path);
     }
   }
 
+  _unwatch(paths) {
+    let removed = false;
+    if (Array.isArray(paths)) {
+      for (let p of paths) {
+        removed = !removed ? this.watchedPaths.delete(p) : true;
+      }
+    } else {
+      removed = this.watchedPaths.delete(paths);
+    }
+    if (removed) this.sendCommand('unwatch', [paths]);
+  }
+
   /**
    * Remove a path from the watcher
    */
@@ -102,36 +248,27 @@ class Watcher {
         let count = this.watchedDirectories.get(dir) - 1;
         if (count === 0) {
           this.watchedDirectories.delete(dir);
-          this.watcher.unwatch(dir);
+          this._unwatch(dir);
         } else {
           this.watchedDirectories.set(dir, count);
         }
       }
     } else {
-      this.watcher.unwatch(path);
+      this._unwatch(path);
     }
   }
 
-  /**
-   * Add an event handler
-   */
-  on(event, callback) {
-    this.watcher.on(event, callback);
-  }
-
-  /**
-   * Add an event handler
-   */
-  once(event, callback) {
-    this.watcher.once(event, callback);
-  }
-
   /**
    * Stop watching all paths
    */
   async stop() {
     this.stopped = true;
-    await this.watcher.close();
+
+    if (this.child) {
+      this.child.kill();
+
+      return new Promise(resolve => this.once('childDead', resolve));
+    }
   }
 }
 
diff --git a/packages/core/watcher/src/child.js b/packages/core/watcher/src/child.js
new file mode 100644
index 00000000000..abf3bcd7dfe
--- /dev/null
+++ b/packages/core/watcher/src/child.js
@@ -0,0 +1,52 @@
+const {FSWatcher} = require('chokidar');
+const {errorUtils} = require('@parcel/utils');
+const optionsTransfer = require('./options');
+
+let watcher;
+function sendEvent(event, path) {
+  process.send({
+    event: event,
+    path: path
+  });
+}
+
+function handleError(e) {
+  sendEvent('watcherError', errorUtils.errorToJson(e));
+}
+
+function init(options) {
+  options = optionsTransfer.decode(options);
+  watcher = new FSWatcher(options);
+  watcher.on('all', sendEvent);
+  sendEvent('ready');
+}
+
+function executeFunction(functionName, args) {
+  try {
+    watcher[functionName](...args);
+  } catch (e) {
+    handleError(e);
+  }
+}
+
+process.on('message', msg => {
+  switch (msg.type) {
+    case 'init':
+      init(msg.options);
+      break;
+    case 'function':
+      executeFunction(msg.name, msg.args);
+      break;
+    case 'die':
+      process.exit();
+      break;
+    case 'emulate_error':
+      throw new Error('this is an emulated error');
+  }
+});
+
+process.on('error', handleError);
+process.on('uncaughtException', handleError);
+process.on('disconnect', () => {
+  process.exit();
+});
diff --git a/packages/core/watcher/src/options.js b/packages/core/watcher/src/options.js
new file mode 100644
index 00000000000..ba3637511f5
--- /dev/null
+++ b/packages/core/watcher/src/options.js
@@ -0,0 +1,40 @@
+function type(options) {
+  return Object.prototype.toString.call(options).slice(8, -1);
+}
+
+function encode(options) {
+  if (options && options.ignored) {
+    const ignoredType = type(options.ignored);
+    if (ignoredType !== 'Array') {
+      options.ignored = [options.ignored];
+    }
+
+    options.ignored.forEach((value, index) => {
+      const valueType = type(value);
+      if (valueType === 'RegExp') {
+        options.ignored[index] = value.source;
+        if (!options._regIndexs) {
+          options._regIndexs = [];
+        }
+        options._regIndexs.push(index);
+      }
+    });
+  }
+
+  return options;
+}
+
+function decode(options) {
+  if (options && options.ignored && options._regIndexs) {
+    for (let index of options._regIndexs) {
+      options.ignored[index] = new RegExp(options.ignored[index]);
+    }
+  }
+
+  delete options._regIndexs;
+
+  return options;
+}
+
+exports.encode = encode;
+exports.decode = decode;
diff --git a/packages/core/watcher/test/.babelrc b/packages/core/watcher/test/.babelrc
new file mode 100644
index 00000000000..eb1af60481b
--- /dev/null
+++ b/packages/core/watcher/test/.babelrc
@@ -0,0 +1,8 @@
+{
+  "presets": [["@babel/preset-env", {
+    "targets": {
+      "node": "current"
+    }
+  }]],
+  "plugins": ["@babel/plugin-transform-runtime"]
+}
diff --git a/packages/core/watcher/test/.eslintrc.json b/packages/core/watcher/test/.eslintrc.json
new file mode 100644
index 00000000000..87769487177
--- /dev/null
+++ b/packages/core/watcher/test/.eslintrc.json
@@ -0,0 +1,6 @@
+{
+  "extends": "../../../../.eslintrc.json",
+  "env": {
+    "mocha": true
+  }
+}
diff --git a/packages/core/watcher/test/changeEvent.js b/packages/core/watcher/test/changeEvent.js
new file mode 100644
index 00000000000..2b7739344d1
--- /dev/null
+++ b/packages/core/watcher/test/changeEvent.js
@@ -0,0 +1,104 @@
+const Watcher = require('../index');
+const fs = require('@parcel/fs');
+const path = require('path');
+const assert = require('assert');
+const {sleep} = require('@parcel/test-utils');
+
+describe('change event', function() {
+  let tmpFolder = path.join(__dirname, './tmp/');
+
+  before(() => {
+    fs.mkdirp(tmpFolder);
+  });
+
+  it('Should emit event on filechange', async () => {
+    let watcher = new Watcher({});
+
+    let filepath = path.join(tmpFolder, 'file1.txt');
+
+    await fs.writeFile(filepath, 'this is a text document');
+
+    watcher.add(filepath);
+
+    let changed = false;
+    watcher.once('change', () => {
+      changed = true;
+    });
+
+    if (!watcher.ready) {
+      await new Promise(resolve => watcher.once('ready', resolve));
+    }
+
+    await sleep(250);
+
+    await fs.writeFile(filepath, 'this is not a text document');
+
+    await sleep(500);
+
+    assert(changed, 'File should be flagged as changed.');
+
+    await watcher.stop();
+  });
+
+  it('Should emit event on filechange using arrays', async () => {
+    let watcher = new Watcher({});
+
+    let filepath = path.join(tmpFolder, 'file1.txt');
+
+    await fs.writeFile(filepath, 'this is a text document');
+
+    watcher.add([filepath]);
+
+    let changed = false;
+    watcher.once('change', () => {
+      changed = true;
+    });
+
+    if (!watcher.ready) {
+      await new Promise(resolve => watcher.once('ready', resolve));
+    }
+
+    await sleep(250);
+
+    await fs.writeFile(filepath, 'this is not a text document');
+
+    await sleep(500);
+
+    assert(changed, 'File should be flagged as changed.');
+
+    await watcher.stop();
+  });
+
+  it('Should not emit event if file has been added and removed', async () => {
+    let watcher = new Watcher({});
+
+    let filepath = path.join(tmpFolder, 'file1.txt');
+
+    await fs.writeFile(filepath, 'this is a text document');
+
+    await sleep(250);
+
+    watcher.add(filepath);
+
+    let changed = false;
+    watcher.once('change', () => {
+      changed = true;
+    });
+
+    if (!watcher.ready) {
+      await new Promise(resolve => watcher.once('ready', resolve));
+    }
+
+    await sleep(250);
+
+    watcher.unwatch(filepath);
+
+    await fs.writeFile(filepath, 'this is not a text document');
+
+    await sleep(500);
+
+    assert(!changed, 'Should not have emitted a change event.');
+
+    await watcher.stop();
+  });
+});
diff --git a/packages/core/watcher/test/errorHandling.js b/packages/core/watcher/test/errorHandling.js
new file mode 100644
index 00000000000..6dd59f05ca3
--- /dev/null
+++ b/packages/core/watcher/test/errorHandling.js
@@ -0,0 +1,84 @@
+const Watcher = require('../index');
+const fs = require('@parcel/fs');
+const path = require('path');
+const assert = require('assert');
+const {sleep} = require('@parcel/test-utils');
+
+describe('error handling', function() {
+  let tmpFolder = path.join(__dirname, './tmp/');
+
+  before(() => {
+    fs.mkdirp(tmpFolder);
+  });
+
+  it('Should restart child process if it dies', async () => {
+    let watcher = new Watcher({});
+
+    let filepath = path.join(tmpFolder, 'file1.txt');
+
+    await fs.writeFile(filepath, 'this is a text document');
+
+    watcher.add(filepath);
+
+    let changed = false;
+    watcher.once('change', () => {
+      changed = true;
+    });
+
+    if (!watcher.ready) {
+      await new Promise(resolve => watcher.once('ready', resolve));
+    }
+
+    await sleep(250);
+
+    watcher._emulateChildDead();
+
+    await sleep(1000);
+
+    await fs.writeFile(filepath, 'this is not a text document');
+
+    await sleep(500);
+
+    assert(changed, 'Should have emitted a change event.');
+
+    await watcher.stop();
+  });
+
+  it('Should restart child process on errors', async () => {
+    let watcher = new Watcher({});
+
+    let filepath = path.join(tmpFolder, 'file1.txt');
+
+    await fs.writeFile(filepath, 'this is a text document');
+
+    watcher.add(filepath);
+
+    let hasThrown = false;
+    watcher.on('watcherError', () => (hasThrown = true));
+
+    let changed = false;
+    watcher.once('change', () => {
+      changed = true;
+    });
+
+    if (!watcher.ready) {
+      await new Promise(resolve => watcher.once('ready', resolve));
+    }
+
+    await sleep(250);
+
+    watcher._emulateChildError();
+
+    await sleep(1000);
+
+    await fs.writeFile(filepath, 'this is not a text document');
+
+    await sleep(500);
+
+    assert(changed, 'Should have emitted a change event.');
+
+    await watcher.stop();
+
+    assert(hasThrown, 'Should have emitted an error event.');
+  });
+});
diff --git a/packages/core/watcher/test/fswatcher.js b/packages/core/watcher/test/fswatcher.js
new file mode 100644
index 00000000000..013e19ba04e
--- /dev/null
+++ b/packages/core/watcher/test/fswatcher.js
@@ -0,0 +1,32 @@
+const Watcher = require('../index');
+const {sleep} = require('@parcel/test-utils');
+const assert = require('assert');
+
+describe('Watcher', function() {
+  it('Should be able to create a new watcher', async () => {
+    let watcher = new Watcher();
+
+    assert(!!watcher.child);
+    assert(!watcher.ready);
+
+    await sleep(1000);
+
+    assert(!!watcher.child);
+    assert(watcher.ready);
+
+    await watcher.stop();
+  });
+
+  it('Should be able to properly destroy the watcher', async () => {
+    let watcher = new Watcher();
+
+    await sleep(1000);
+
+    assert(!!watcher.child);
+    assert(watcher.ready);
+
+    let time = Date.now();
+    await watcher.stop();
+    assert.notEqual(time, Date.now());
+  });
+});
diff --git a/packages/core/watcher/test/mocha.opts b/packages/core/watcher/test/mocha.opts
new file mode 100644
index 00000000000..0d00e6a708a
--- /dev/null
+++ b/packages/core/watcher/test/mocha.opts
@@ -0,0 +1,3 @@
+--require @parcel/babel-register
+--timeout 10000
+--exit
\ No newline at end of file
diff --git a/packages/core/watcher/test/options.js b/packages/core/watcher/test/options.js
new file mode 100644
index 00000000000..6f23d797724
--- /dev/null
+++ b/packages/core/watcher/test/options.js
@@ -0,0 +1,124 @@
+const Watcher = require('../index');
+const fs = require('@parcel/fs');
+const path = require('path');
+const assert = require('assert');
+const {sleep} = require('@parcel/test-utils');
+
+describe('options', function() {
+  let tmpFolder = path.join(__dirname, './tmp/');
+
+  before(() => {
+    fs.mkdirp(tmpFolder);
+  });
+
+  it('Should pass init options with correct ignored regex', async () => {
+    let watcher = new Watcher({
+      ignored: /file/
+    });
+
+    let filepath = path.join(tmpFolder, 'file1.txt');
+    await fs.writeFile(filepath, 'this is a text document');
+
+    watcher.add(filepath);
+
+    let changed = false;
+    watcher.once('change', () => {
+      changed = true;
+    });
+
+    if (!watcher.ready) {
+      await new Promise(resolve => watcher.once('ready', resolve));
+    }
+
+    await sleep(250);
+
+    await fs.writeFile(filepath, 'this is not a text document');
+
+    await sleep(500);
+
+    assert(!changed, 'File should not be flagged as changed.');
+
+    await watcher.stop();
+  });
+
+  it('Should pass init options with a more complex ignored regex', async () => {
+    let watcher = new Watcher({
+      ignored: /file|config/
+    });
+
+    let filepaths = [
+      path.join(tmpFolder, 'file1.txt'),
+      path.join(tmpFolder, 'config.json')
+    ];
+
+    for (let filepath of filepaths) {
+      await fs.writeFile(filepath, 'this is a text document');
+
+      watcher.add(filepath);
+    }
+
+    let changed = false;
+    watcher.once('change', () => {
+      changed = true;
+    });
+
+    if (!watcher.ready) {
+      await new Promise(resolve => watcher.once('ready', resolve));
+    }
+
+    await sleep(250);
+
+    for (let filepath of filepaths) {
+      await fs.writeFile(filepath, 'this is not a text document');
+
+      watcher.add(filepath);
+    }
+
+    await sleep(500);
+
+    assert(!changed, 'File should not be flagged as changed.');
+
+    await watcher.stop();
+  });
+
+  it('Should not ignore any files outside of the regex', async () => {
+    let watcher = new Watcher({
+      ignored: /file|config/
+    });
+
+    let filepaths = [
+      path.join(tmpFolder, 'file1.txt'),
+      path.join(tmpFolder, 'config.json'),
+      path.join(tmpFolder, 'something')
+    ];
+
+    for (let filepath of filepaths) {
+      await fs.writeFile(filepath, 'this is a text document');
+
+      watcher.add(filepath);
+    }
+
+    let changed = 0;
+    watcher.once('change', () => {
+      changed++;
+    });
+
+    if (!watcher.ready) {
+      await new Promise(resolve => watcher.once('ready', resolve));
+    }
+
+    await sleep(250);
+
+    for (let filepath of filepaths) {
+      await fs.writeFile(filepath, 'this is not a text document');
+
+      watcher.add(filepath);
+    }
+
+    await sleep(500);
+
+    assert.equal(changed, 1, 'One file should have changed once.');
+
+    await watcher.stop();
+  });
+});
diff --git a/packages/core/watcher/test/watched.js b/packages/core/watcher/test/watched.js
new file mode 100644
index 00000000000..2ed3e6aac8e
--- /dev/null
+++ b/packages/core/watcher/test/watched.js
@@ -0,0 +1,28 @@
+const Watcher = require('../index');
+const fs = require('@parcel/fs');
+const path = require('path');
+const assert = require('assert');
+
+describe('watched paths', function() {
+  let tmpFolder = path.join(__dirname, './tmp/');
+
+  before(() => {
+    fs.mkdirp(tmpFolder);
+  });
+
+  it('Should return watched paths', async () => {
+    let watcher = new Watcher({});
+
+    let filepath = path.join(tmpFolder, 'file1.txt');
+    await fs.writeFile(filepath, 'this is a text document');
+
+    watcher.add(filepath);
+
+    assert(
+      Object.keys(watcher.getWatched())[0] === filepath,
+      'getWatched should return all the watched paths.'
+    );
+
+    await watcher.stop();
+  });
+});
diff --git a/packages/core/workers/package.json b/packages/core/workers/package.json
index 5715db344b7..2f2e9827fd7 100644
--- a/packages/core/workers/package.json
+++ b/packages/core/workers/package.json
@@ -23,6 +23,7 @@
     "mocha": "^5.2.0"
   },
   "dependencies": {
-    "physical-cpu-count": "^2.0.0"
+    "physical-cpu-count": "^2.0.0",
+    "@parcel/utils": "^1.10.3"
   }
 }
diff --git a/packages/core/workers/src/Worker.js b/packages/core/workers/src/Worker.js
index 9dd266a82c5..851d3f415dc 100644
--- a/packages/core/workers/src/Worker.js
+++ b/packages/core/workers/src/Worker.js
@@ -1,6 +1,6 @@
 const childProcess = require('child_process');
 const {EventEmitter} = require('events');
-const errorUtils = require('./errorUtils');
+const {errorUtils} = require('@parcel/utils');
 
 const childModule = require.resolve('./child');
 
diff --git a/packages/core/workers/src/WorkerFarm.js b/packages/core/workers/src/WorkerFarm.js
index b7af519d350..5cfcff22cab 100644
--- a/packages/core/workers/src/WorkerFarm.js
+++ b/packages/core/workers/src/WorkerFarm.js
@@ -1,5 +1,5 @@
 const {EventEmitter} = require('events');
-const errorUtils = require('./errorUtils');
+const {errorUtils} = require('@parcel/utils');
 const Worker = require('./Worker');
 const cpuCount = require('./cpuCount');
 
diff --git a/packages/core/workers/src/child.js b/packages/core/workers/src/child.js
index 9483779ac95..a6b5a4e7bc0 100644
--- a/packages/core/workers/src/child.js
+++ b/packages/core/workers/src/child.js
@@ -1,4 +1,4 @@
-const errorUtils = require('./errorUtils');
+const {errorUtils} = require('@parcel/utils');
 
 class Child {
   constructor() {