diff --git a/.travis.yml b/.travis.yml
index 7b6113aa0..9ac8cc72a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -13,14 +13,8 @@ compiler: clang
 
 matrix:
   include:
-    - os: linux
-      env: NODE_VERSION=0.12
     - os: linux
       env: NODE_VERSION=4
-    - os: osx
-      env: ATOM_SPECS_TASK=core NODE_VERSION=0.12
-    - os: osx
-      env: ATOM_SPECS_TASK=packages NODE_VERSION=0.12
 
 sudo: false
 
@@ -28,16 +22,15 @@ install:
   - git clone https://github.com/creationix/nvm.git /tmp/.nvm
   - source /tmp/.nvm/nvm.sh
   - nvm install $NODE_VERSION
-  - nvm use $NODE_VERSION
+  - nvm use --delete-prefix $NODE_VERSION
 
 script: script/cibuild
 
 cache:
   directories:
     - node_modules
-    - build/node_modules
     - apm/node_modules
-    - $HOME/.atom/compile-cache
+    - build/node_modules
 
 notifications:
   email:
@@ -46,8 +39,11 @@ notifications:
 
 addons:
   apt:
+    sources:
+    - ubuntu-toolchain-r-test
     packages:
     - build-essential
     - git
     - libgnome-keyring-dev
     - fakeroot
+    - gcc-multilib
diff --git a/Dockerfile b/Dockerfile
index d792c30c5..22a101743 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -2,7 +2,7 @@
 # DESCRIPTION:    Image to build Atom and create a .rpm file
 
 # Base docker image
-FROM fedora:21
+FROM nodesource/fedora21:4.2.6
 
 # Install dependencies
 RUN yum install -y \
@@ -12,11 +12,9 @@ RUN yum install -y \
     glibc-devel \
     git-core \
     libgnome-keyring-devel \
-    rpmdevtools \
-    nodejs \
-    npm
+    rpmdevtools
 
-RUN npm install -g npm@1.4.28 --loglevel error
+RUN npm install -g npm --loglevel error
 
 ADD . /atom
 WORKDIR /atom
diff --git a/ISSUE_TEMPLATE.md b/ISSUE_TEMPLATE.md
index 5b3ea42f4..d2ac45f05 100644
--- a/ISSUE_TEMPLATE.md
+++ b/ISSUE_TEMPLATE.md
@@ -1,6 +1,6 @@
 ### Prerequisites
 
-* [ ] Can you reproduce the problem in [safe mode](http://flight-manual.atom.io/hacking-atom/sections/debugging/#check-if-the-problem-shows-up-in-safe-mode)?
+* [ ] Can you reproduce the problem in [safe mode](http://flight-manual.atom.io/hacking-atom/sections/debugging/#using-safe-mode)?
 * [ ] Are you running the [latest version of Atom](http://flight-manual.atom.io/hacking-atom/sections/debugging/#update-to-the-latest-version)?
 * [ ] Did you check the [debugging guide](http://flight-manual.atom.io/hacking-atom/sections/debugging/)?
 * [ ] Did you check the [FAQs on Discuss](https://discuss.atom.io/c/faq)?
diff --git a/README.md b/README.md
index 9f052ccff..a41ddeb64 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 ![Atom](https://cloud.githubusercontent.com/assets/72919/2874231/3af1db48-d3dd-11e3-98dc-6066f8bc766f.png)
 
-[![macOS Build Status](https://travis-ci.org/atom/atom.svg?branch=master)](https://travis-ci.org/atom/atom) [![Windows Build Status](https://ci.appveyor.com/api/projects/status/1tkktwh654w07eim?svg=true)](https://ci.appveyor.com/project/Atom/atom)
+[![macOS Build Status](https://circleci.com/gh/atom/atom.svg?style=svg)](https://circleci.com/gh/atom/atom) [![Linux Build Status](https://travis-ci.org/atom/atom.svg?branch=master)](https://travis-ci.org/atom/atom) [![Windows Build Status](https://ci.appveyor.com/api/projects/status/1tkktwh654w07eim?svg=true)](https://ci.appveyor.com/project/Atom/atom)
 [![Dependency Status](https://david-dm.org/atom/atom.svg)](https://david-dm.org/atom/atom)
 [![Join the Atom Community on Slack](http://atom-slack.herokuapp.com/badge.svg)](http://atom-slack.herokuapp.com/)
 
diff --git a/apm/package.json b/apm/package.json
index d4fcc851a..31162dcaf 100644
--- a/apm/package.json
+++ b/apm/package.json
@@ -6,6 +6,6 @@
     "url": "https://github.com/atom/atom.git"
   },
   "dependencies": {
-    "atom-package-manager": "1.10.0"
+    "atom-package-manager": "1.12.5"
   }
 }
diff --git a/appveyor.yml b/appveyor.yml
index 51e074a4c..316701aae 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -1,9 +1,5 @@
 version: "{build}"
 
-branches:
-  only:
-    - master
-
 skip_tags: true
 clone_folder: c:\projects\atom
 clone_depth: 10
@@ -16,9 +12,10 @@ environment:
     ATOM_DEV_RESOURCE_PATH: c:\projects\atom
     ATOM_ACCESS_TOKEN:
       secure: Q7vxmSq0bVCLTTRPzXw5ZhPTe7XYhWxX0tQV6neEkddTH6pZkOYNmSCG6VnMX2f+
+    ATOM_NOISY_BUILD: 1
 
   matrix:
-  - NODE_VERSION: 0.10.35
+  - NODE_VERSION: 4.4.5
 
 install:
   - SET PATH=C:\Program Files\Atom\resources\cli;%PATH%
@@ -37,6 +34,9 @@ artifacts:
     name: AtomSetup.msi
 
 cache:
+  - '%APPVEYOR_BUILD_FOLDER%\build\node_modules'
+  - '%APPVEYOR_BUILD_FOLDER%\apm\node_modules'
+  - '%APPVEYOR_BUILD_FOLDER%\node_modules'
   - '%USERPROFILE%\.atom\.apm'
   - '%USERPROFILE%\.atom\.node-gyp\.atom'
   - '%USERPROFILE%\.atom\.npm'
diff --git a/build/Gruntfile.coffee b/build/Gruntfile.coffee
index b248eda2e..5cf88175e 100644
--- a/build/Gruntfile.coffee
+++ b/build/Gruntfile.coffee
@@ -14,6 +14,8 @@ _ = require 'underscore-plus'
 packageJson = require '../package.json'
 
 module.exports = (grunt) ->
+  process.env.ATOM_RESOURCE_PATH ?= path.resolve(__dirname, '..')
+
   require('time-grunt')(grunt)
 
   grunt.loadNpmTasks('grunt-babel')
@@ -296,7 +298,9 @@ module.exports = (grunt) ->
     ciTasks.push('create-windows-installer:installer')
     ciTasks.push('codesign:installer') if process.env.JANKY_SIGNTOOL
     ciTasks.push('codesign:cleanup')
-  ciTasks.push('publish-build') unless process.env.CI
+
+  if process.env.ATOM_PUBLISH_REPO or not process.env.CI
+    ciTasks.push('publish-build')
 
   grunt.registerTask('ci', ciTasks)
 
diff --git a/build/package.json b/build/package.json
index 2f8d88d8a..533f49417 100644
--- a/build/package.json
+++ b/build/package.json
@@ -32,7 +32,7 @@
     "grunt-standard": "^2.0.0",
     "legal-eagle": "~0.13.0",
     "minidump": "~0.9",
-    "npm": "2.13.3",
+    "npm": "3.10.5",
     "rcedit": "~0.3.0",
     "request": "~2.27.0",
     "rimraf": "~2.2.2",
diff --git a/build/tasks/compile-packages-slug-task.coffee b/build/tasks/compile-packages-slug-task.coffee
index 7317f158a..f6f297bec 100644
--- a/build/tasks/compile-packages-slug-task.coffee
+++ b/build/tasks/compile-packages-slug-task.coffee
@@ -40,6 +40,8 @@ module.exports = (grunt) ->
       continue if path.basename(moduleDirectory) is '.bin'
 
       metadataPath = path.join(moduleDirectory, 'package.json')
+      continue unless fs.existsSync(metadataPath)
+
       metadata = grunt.file.readJSON(metadataPath)
       continue unless metadata?.engines?.atom?
 
diff --git a/build/tasks/publish-build-task.coffee b/build/tasks/publish-build-task.coffee
index 2802f827d..ad31c0d8e 100644
--- a/build/tasks/publish-build-task.coffee
+++ b/build/tasks/publish-build-task.coffee
@@ -11,7 +11,7 @@ AWS = require 'aws-sdk'
 grunt = null
 
 token = process.env.ATOM_ACCESS_TOKEN
-repo = process.env.ATOM_REPO ? 'atom/atom'
+repo = process.env.ATOM_PUBLISH_REPO ? 'atom/atom'
 defaultHeaders =
   Authorization: "token #{token}"
   'User-Agent': 'Atom'
@@ -34,7 +34,12 @@ module.exports = (gruntObject) ->
   grunt.registerTask 'upload-assets', 'Upload the assets to a GitHub release', ->
     releaseBranch = grunt.config.get('atom.releaseBranch')
     isPrerelease = grunt.config.get('atom.channel') is 'beta'
-    return unless releaseBranch?
+
+    unless releaseBranch?
+      grunt.log.ok("Skipping upload-assets to #{repo} repo because this is not a release branch")
+      return
+
+    grunt.log.ok("Starting upload-assets to #{repo} repo")
 
     doneCallback = @async()
     startTime = Date.now()
@@ -119,6 +124,7 @@ logError = (message, error, details) ->
 
 zipAssets = (buildDir, assets, callback) ->
   zip = (directory, sourcePath, assetName, callback) ->
+    grunt.log.ok("Zipping #{sourcePath} into #{assetName}")
     if process.platform is 'win32'
       sevenZipPath = if process.env.JANKY_SHA1? then "C:/psmodules/" else ""
       zipCommand = "#{sevenZipPath}7z.exe a -r \"#{assetName}\" \"#{sourcePath}\""
@@ -136,6 +142,7 @@ zipAssets = (buildDir, assets, callback) ->
   async.parallel(tasks, callback)
 
 getAtomDraftRelease = (isPrerelease, branchName, callback) ->
+  grunt.log.ok("Obtaining GitHub draft release for #{branchName}")
   atomRepo = new GitHub({repo: repo, token})
   atomRepo.getReleases {prerelease: isPrerelease}, (error, releases=[]) ->
     if error?
@@ -154,12 +161,14 @@ getAtomDraftRelease = (isPrerelease, branchName, callback) ->
             logError('Fetching draft release assets failed', error, assets)
             callback(error ? new Error(response.statusCode))
           else
+            grunt.log.ok("Using GitHub draft release #{firstDraft.name}")
             firstDraft.assets = assets
             callback(null, firstDraft)
       else
         createAtomDraftRelease(isPrerelease, branchName, callback)
 
 createAtomDraftRelease = (isPrerelease, branchName, callback) ->
+  grunt.log.ok("Creating GitHub draft release #{branchName}")
   {version} = require('../../package.json')
   options =
     uri: "https://api.github.com/repos/#{repo}/releases"
@@ -185,6 +194,7 @@ createAtomDraftRelease = (isPrerelease, branchName, callback) ->
       callback(null, body)
 
 deleteRelease = (release) ->
+  grunt.log.ok("Deleting GitHub release #{release.tag_name}")
   options =
     uri: release.url
     method: 'DELETE'
@@ -195,6 +205,7 @@ deleteRelease = (release) ->
       logError('Deleting release failed', error, body)
 
 deleteExistingAssets = (release, assetNames, callback) ->
+  grunt.log.ok("Deleting #{assetNames.join(',')} from GitHub release #{release.tag_name}")
   [callback, assetNames] = [assetNames, callback] if not callback?
 
   deleteAsset = (url, callback) ->
@@ -216,6 +227,7 @@ deleteExistingAssets = (release, assetNames, callback) ->
 
 uploadAssets = (release, buildDir, assets, callback) ->
   uploadToReleases = (release, assetName, assetPath, callback) ->
+    grunt.log.ok("Uploading #{assetName} to GitHub release #{release.tag_name}")
     options =
       uri: release.upload_url.replace(/\{.*$/, "?name=#{assetName}")
       method: 'POST'
@@ -248,6 +260,7 @@ uploadAssets = (release, buildDir, assets, callback) ->
     s3 = new AWS.S3 s3Info
 
     key = "releases/#{release.tag_name}/#{assetName}"
+    grunt.log.ok("Uploading to S3 #{key}")
     uploadParams =
       Bucket: s3Bucket
       ACL: 'public-read'
diff --git a/circle.yml b/circle.yml
index a55900cca..95ebb024c 100644
--- a/circle.yml
+++ b/circle.yml
@@ -1,4 +1,38 @@
+machine:
+  environment:
+    XCODE_SCHEME: test
+    XCODE_WORKSPACE: test
+    XCODE_PROJECT: test
+
+  xcode:
+    version: 7.3
+
 general:
-  branches:
-    only:
-      - io-circle-ci
+  artifacts:
+    - out/Atom.zip
+
+dependencies:
+  pre:
+    - curl -o- https://raw.githubusercontent.com/creationix/nvm/v0.31.3/install.sh | bash
+    - nvm install 4.4.7
+    - nvm use 4.4.7
+    - npm install -g npm
+    - script/fingerprint-clean
+
+  override:
+    - script/bootstrap
+
+  post:
+    - script/fingerprint-write
+
+  cache_directories:
+    - apm/node_modules
+    - build/node_modules
+    - node_modules
+
+test:
+  override:
+    - script/grunt ci
+
+  post:
+    - zip -r out/Atom.zip out/Atom.app
diff --git a/exports/atom.coffee b/exports/atom.coffee
index 81d1726b8..bd8a1b62c 100644
--- a/exports/atom.coffee
+++ b/exports/atom.coffee
@@ -18,6 +18,10 @@ module.exports =
   Disposable: Disposable
   CompositeDisposable: CompositeDisposable
 
+# Shell integration is required by both Squirrel and Settings-View
+if process.platform is 'win32'
+  module.exports.WinShell = require '../src/main-process/win-shell'
+
 # The following classes can't be used from a Task handler and should therefore
 # only be exported when not running as a child node process
 unless process.env.ATOM_SHELL_INTERNAL_RUN_AS_NODE
diff --git a/package.json b/package.json
index f33c3fa0e..5609f48c8 100644
--- a/package.json
+++ b/package.json
@@ -61,6 +61,7 @@
     "text-buffer": "9.2.2",
     "typescript-simple": "1.0.0",
     "underscore-plus": "^1.6.6",
+    "winreg": "^1.2.1",
     "yargs": "^3.23.0"
   },
   "packageDependencies": {
@@ -70,8 +71,8 @@
     "atom-light-ui": "0.44.0",
     "base16-tomorrow-dark-theme": "1.1.0",
     "base16-tomorrow-light-theme": "1.1.1",
-    "one-dark-ui": "1.4.0",
-    "one-light-ui": "1.4.0",
+    "one-dark-ui": "1.5.0",
+    "one-light-ui": "1.5.0",
     "one-dark-syntax": "1.3.0",
     "one-light-syntax": "1.3.0",
     "solarized-dark-syntax": "1.0.2",
@@ -108,50 +109,50 @@
     "notifications": "0.65.0",
     "open-on-github": "1.2.0",
     "package-generator": "1.0.0",
-    "settings-view": "0.240.1",
+    "settings-view": "0.241.0",
     "snippets": "1.0.2",
     "spell-check": "0.67.1",
     "status-bar": "1.4.0",
     "styleguide": "0.47.0",
     "symbols-view": "0.113.0",
-    "tabs": "0.99.0",
-    "timecop": "0.33.1",
-    "tree-view": "0.208.1",
+    "tabs": "0.100.0",
+    "timecop": "0.33.2",
+    "tree-view": "0.208.2",
     "update-package-dependencies": "0.10.0",
     "welcome": "0.34.0",
-    "whitespace": "0.32.2",
+    "whitespace": "0.33.0",
     "wrap-guide": "0.38.1",
     "language-c": "0.52.1",
     "language-clojure": "0.21.0",
-    "language-coffee-script": "0.47.1",
+    "language-coffee-script": "0.47.2",
     "language-csharp": "0.12.1",
-    "language-css": "0.37.0",
+    "language-css": "0.37.1",
     "language-gfm": "0.88.0",
-    "language-git": "0.14.0",
-    "language-go": "0.42.0",
-    "language-html": "0.44.1",
+    "language-git": "0.15.0",
+    "language-go": "0.42.1",
+    "language-html": "0.45.1",
     "language-hyperlink": "0.16.0",
     "language-java": "0.23.0",
     "language-javascript": "0.119.0",
-    "language-json": "0.18.1",
-    "language-less": "0.29.4",
+    "language-json": "0.18.2",
+    "language-less": "0.29.5",
     "language-make": "0.22.2",
     "language-mustache": "0.13.0",
     "language-objective-c": "0.15.1",
     "language-perl": "0.35.0",
-    "language-php": "0.37.1",
+    "language-php": "0.37.2",
     "language-property-list": "0.8.0",
     "language-python": "0.45.0",
-    "language-ruby": "0.68.6",
+    "language-ruby": "0.69.0",
     "language-ruby-on-rails": "0.25.0",
-    "language-sass": "0.55.0",
+    "language-sass": "0.56.0",
     "language-shellscript": "0.22.4",
     "language-source": "0.9.0",
-    "language-sql": "0.22.0",
+    "language-sql": "0.23.0",
     "language-text": "0.7.1",
     "language-todo": "0.28.0",
     "language-toml": "0.18.0",
-    "language-xml": "0.34.8",
+    "language-xml": "0.34.9",
     "language-yaml": "0.26.0"
   },
   "private": true,
diff --git a/script/bootstrap b/script/bootstrap
index 3b9a35735..6fcf8fef0 100755
--- a/script/bootstrap
+++ b/script/bootstrap
@@ -75,7 +75,7 @@ function bootstrap() {
 
   var buildInstallCommand = initialNpmCommand + npmFlags + 'install';
   var buildInstallOptions = {cwd: path.resolve(__dirname, '..', 'build')};
-  var apmInstallCommand = npmPath + npmFlags + '--target=0.10.40 ' + 'install';
+  var apmInstallCommand = npmPath + npmFlags + '--target=4.4.5 --global-style ' + 'install';
   var apmInstallOptions = {cwd: apmInstallPath};
   var moduleInstallCommand = apmPath + ' install' + apmFlags;
   var dedupeApmCommand = apmPath + ' dedupe' + apmFlags;
@@ -97,7 +97,7 @@ function bootstrap() {
   }
   var moduleInstallOptions = {env: moduleInstallEnv};
 
-  if (process.argv.indexOf('--no-quiet') === -1) {
+  if (process.argv.indexOf('--no-quiet') === -1 || process.env.ATOM_NOISY_BUILD) {
     buildInstallCommand  += ' --loglevel error';
     apmInstallCommand    += ' --loglevel error';
     moduleInstallCommand += ' --loglevel error';
@@ -122,11 +122,6 @@ function bootstrap() {
       message: 'Installing apm...',
       options: apmInstallOptions
     },
-    {
-      command: apmPath + ' clean' + apmFlags,
-      message: 'Deleting old packages...',
-      options: moduleInstallOptions
-    },
     {
       command: moduleInstallCommand,
       options: moduleInstallOptions
diff --git a/script/cibuild b/script/cibuild
index 627c2291a..6f16ac5cd 100755
--- a/script/cibuild
+++ b/script/cibuild
@@ -40,10 +40,6 @@ function setEnvironmentVariables() {
     process.env.CC = 'clang';
     process.env.CXX = 'clang++';
     process.env.npm_config_clang = '1';
-  } else if (process.platform === 'win32') {
-    process.env.BUILD_ATOM_RELEASES_S3_KEY = process.env.BUILD_ATOM_WIN_RELEASES_S3_KEY
-    process.env.BUILD_ATOM_RELEASES_S3_SECRET = process.env.BUILD_ATOM_WIN_RELEASES_S3_SECRET
-    process.env.BUILD_ATOM_RELEASES_S3_BUCKET = process.env.BUILD_ATOM_WIN_RELEASES_S3_BUCKET
   }
 }
 
diff --git a/script/cibuild-atom-linux b/script/cibuild-atom-linux
index 2c3395608..fe79c19fe 100755
--- a/script/cibuild-atom-linux
+++ b/script/cibuild-atom-linux
@@ -7,10 +7,11 @@ export BUILD_ATOM_RELEASES_S3_KEY=$BUILD_ATOM_LINUX_RELEASES_S3_KEY
 export BUILD_ATOM_RELEASES_S3_SECRET=$BUILD_ATOM_LINUX_RELEASES_S3_SECRET
 export BUILD_ATOM_RELEASES_S3_BUCKET=$BUILD_ATOM_LINUX_RELEASES_S3_BUCKET
 
-if [ -d /usr/local/share/nodenv ]; then
-  export NODENV_ROOT=/usr/local/share/nodenv
-  export PATH=/usr/local/share/nodenv/bin:/usr/local/share/nodenv/shims:$PATH
-  export NODENV_VERSION="v0.10.21"
-fi
+rm -rf /tmp/.atom-nvm
+git clone https://github.com/creationix/nvm.git /tmp/.atom-nvm
+source /tmp/.atom-nvm/nvm.sh
+nvm install 4.4.7
+nvm use 4.4.7
+npm install -g npm
 
 script/cibuild
diff --git a/script/fingerprint-clean b/script/fingerprint-clean
new file mode 100755
index 000000000..659395190
--- /dev/null
+++ b/script/fingerprint-clean
@@ -0,0 +1,29 @@
+#!/usr/bin/env node
+var fingerprint = require('./utils/fingerprint')
+var fs = require('fs')
+var path = require('path')
+
+if (!fs.existsSync(path.resolve(__dirname, '..', 'node_modules', '.atom-ci-fingerprint'))) {
+  return
+}
+
+if (fingerprint.fingerprintMatches()) {
+  console.log('node_modules matches current fingerprint ' + fingerprint.fingerprint() + ' - not removing')
+  return
+}
+
+var fsPlus
+try {
+  fsPlus = require('fs-plus')
+} catch (error) {
+  console.log(error.message)
+  return
+}
+
+try {
+  fsPlus.removeSync(path.resolve(__dirname, '..', 'node_modules'))
+  fsPlus.removeSync(path.resolve(__dirname, '..', 'apm', 'node_modules'))
+} catch (error) {
+  console.error(error.message)
+  process.exit(1)
+}
diff --git a/script/fingerprint-write b/script/fingerprint-write
new file mode 100755
index 000000000..e5fad4d72
--- /dev/null
+++ b/script/fingerprint-write
@@ -0,0 +1,2 @@
+#!/usr/bin/env node
+require('./utils/fingerprint').writeFingerprint()
diff --git a/script/utils/fingerprint.js b/script/utils/fingerprint.js
index c419ba4fd..e1f6276d2 100644
--- a/script/utils/fingerprint.js
+++ b/script/utils/fingerprint.js
@@ -6,12 +6,14 @@ var fingerprintPath = path.resolve(__dirname, '..', '..', 'node_modules', '.atom
 
 module.exports = {
   fingerprint: function () {
-    var packageJson = fs.readFileSync(path.resolve(__dirname, '..', '..', 'package.json'))
+    var atomPackageJson = fs.readFileSync(path.resolve(__dirname, '..', '..', 'package.json'))
+    var apmPackageJson = fs.readFileSync(path.resolve(__dirname, '..', '..', 'apm', 'package.json'))
 
     //Include the electron minor version in the fingerprint since that changing requires a re-install
-    var electronVersion = JSON.parse(packageJson).electronVersion.replace(/\.\d+$/, '')
+    var electronVersion = JSON.parse(atomPackageJson).electronVersion.replace(/\.\d+$/, '')
+    var apmVersion = JSON.parse(apmPackageJson).dependencies['atom-package-manager']
 
-    var body = electronVersion + process.platform + process.version
+    var body = electronVersion + apmVersion + process.platform + process.version
     return crypto.createHash('sha1').update(body).digest('hex')
   },
 
diff --git a/spec/squirrel-update-spec.coffee b/spec/squirrel-update-spec.coffee
index a8a39eb54..2fe944e41 100644
--- a/spec/squirrel-update-spec.coffee
+++ b/spec/squirrel-update-spec.coffee
@@ -5,7 +5,7 @@ temp = require 'temp'
 SquirrelUpdate = require '../src/main-process/squirrel-update'
 Spawner = require '../src/main-process/spawner'
 WinPowerShell = require '../src/main-process/win-powershell'
-WinRegistry = require '../src/main-process/win-registry'
+WinShell = require '../src/main-process/win-shell'
 
 # Run passed callback as Spawner.spawn() would do
 invokeCallback = (callback) ->
@@ -26,12 +26,16 @@ describe "Windows Squirrel Update", ->
       # do nothing on command, just run passed callback
       invokeCallback callback
 
-    # Prevent any actual change to Windows registry
-    for own method of WinRegistry
-      # all WinRegistry APIs share the same signature
-      spyOn(WinRegistry, method).andCallFake (callback) ->
-        # do nothing on registry, just run passed callback
-        invokeCallback callback
+    # Prevent any actual change to Windows Shell
+    class FakeShellOption
+      isRegistered: (callback) -> callback true
+      register: (callback) -> callback null
+      deregister: (callback) -> callback null, true
+      update: (callback) -> callback null
+    WinShell.fileHandler = new FakeShellOption()
+    WinShell.fileContextMenu = new FakeShellOption()
+    WinShell.folderContextMenu = new FakeShellOption()
+    WinShell.folderBackgroundContextMenu = new FakeShellOption()
 
   it "quits the app on all squirrel events", ->
     app = quit: jasmine.createSpy('quit')
diff --git a/src/config.coffee b/src/config.coffee
index 27ea1edef..1d314ada1 100644
--- a/src/config.coffee
+++ b/src/config.coffee
@@ -786,9 +786,10 @@ class Config
         rootSchema = properties[key]
 
     Object.assign rootSchema, schema
-    @setDefaults(keyPath, @extractDefaultsFromSchema(schema))
-    @setScopedDefaultsFromSchema(keyPath, schema)
-    @resetSettingsForSchemaChange()
+    @transact =>
+      @setDefaults(keyPath, @extractDefaultsFromSchema(schema))
+      @setScopedDefaultsFromSchema(keyPath, schema)
+      @resetSettingsForSchemaChange()
 
   load: ->
     @initializeConfigDirectory()
@@ -958,9 +959,10 @@ class Config
   setDefaults: (keyPath, defaults) ->
     if defaults? and isPlainObject(defaults)
       keys = splitKeyPath(keyPath)
-      for key, childValue of defaults
-        continue unless defaults.hasOwnProperty(key)
-        @setDefaults(keys.concat([key]).join('.'), childValue)
+      @transact =>
+        for key, childValue of defaults
+          continue unless defaults.hasOwnProperty(key)
+          @setDefaults(keys.concat([key]).join('.'), childValue)
     else
       try
         defaults = @makeValueConformToSchema(keyPath, defaults)
diff --git a/src/crash-reporter-start.coffee b/src/crash-reporter-start.coffee
deleted file mode 100644
index 37c381473..000000000
--- a/src/crash-reporter-start.coffee
+++ /dev/null
@@ -1,13 +0,0 @@
-module.exports = (extra) ->
-  # Breakpad on Mac OS X must be running on UI and non-UI processes
-  # Crashpad on Windows and Linux should only be running on non-UI process
-  return if process.type is 'renderer' and process.platform isnt 'darwin'
-
-  {crashReporter} = require 'electron'
-
-  crashReporter.start({
-    productName: 'Atom',
-    companyName: 'GitHub',
-    submitURL: 'http://54.249.141.255:1127/post'
-    extra: extra
-  })
diff --git a/src/crash-reporter-start.js b/src/crash-reporter-start.js
new file mode 100644
index 000000000..98b210d06
--- /dev/null
+++ b/src/crash-reporter-start.js
@@ -0,0 +1,10 @@
+module.exports = function (extra) {
+  const {crashReporter} = require('electron')
+  crashReporter.start({
+    productName: 'Atom',
+    companyName: 'GitHub',
+    submitURL: 'https://crashreporter.atom.io',
+    autoSubmit: false,
+    extra: extra
+  })
+}
diff --git a/src/main-process/atom-portable.coffee b/src/main-process/atom-portable.coffee
deleted file mode 100644
index ae4bb67ec..000000000
--- a/src/main-process/atom-portable.coffee
+++ /dev/null
@@ -1,35 +0,0 @@
-fs = require 'fs-plus'
-path = require 'path'
-{ipcMain} = require 'electron'
-
-module.exports =
-class AtomPortable
-  @getPortableAtomHomePath: ->
-    execDirectoryPath = path.dirname(process.execPath)
-    path.join(execDirectoryPath, '..', '.atom')
-
-  @setPortable: (existingAtomHome) ->
-    fs.copySync(existingAtomHome, @getPortableAtomHomePath())
-
-  @isPortableInstall: (platform, environmentAtomHome, defaultHome) ->
-    return false unless platform in ['linux', 'win32']
-    return false if environmentAtomHome
-    return false if not fs.existsSync(@getPortableAtomHomePath())
-    # currently checking only that the directory exists  and is writable,
-    # probably want to do some integrity checks on contents in future
-    @isPortableAtomHomePathWritable(defaultHome)
-
-  @isPortableAtomHomePathWritable: (defaultHome) ->
-    writable = false
-    message = ""
-    try
-      writePermissionTestFile = path.join(@getPortableAtomHomePath(), "write.test")
-      fs.writeFileSync(writePermissionTestFile, "test") if not fs.existsSync(writePermissionTestFile)
-      fs.removeSync(writePermissionTestFile)
-      writable = true
-    catch error
-      message = "Failed to use portable Atom home directory (#{@getPortableAtomHomePath()}).  Using the default instead (#{defaultHome}).  #{error.message}"
-
-    ipcMain.on 'check-portable-home-writable', (event) ->
-      event.sender.send 'check-portable-home-writable-response', {writable, message}
-    writable
diff --git a/src/main-process/atom-portable.js b/src/main-process/atom-portable.js
new file mode 100644
index 000000000..7d395c0e7
--- /dev/null
+++ b/src/main-process/atom-portable.js
@@ -0,0 +1,58 @@
+const fs = require('fs-plus')
+const path = require('path')
+const {ipcMain} = require('electron')
+
+module.exports = class AtomPortable {
+  static getPortableAtomHomePath () {
+    const execDirectoryPath = path.dirname(process.execPath)
+    return path.join(execDirectoryPath, '..', '.atom')
+  }
+
+  static setPortable (existingAtomHome) {
+    fs.copySync(existingAtomHome, this.getPortableAtomHomePath())
+  }
+
+  static isPortableInstall (platform, environmentAtomHome, defaultHome) {
+    if (!['linux', 'win32'].includes(platform)) {
+      return false
+    }
+
+    if (environmentAtomHome) {
+      return false
+    }
+
+    if (!fs.existsSync(this.getPortableAtomHomePath())) {
+      return false
+    }
+
+    // Currently checking only that the directory exists and is writable,
+    // probably want to do some integrity checks on contents in future.
+    return this.isPortableAtomHomePathWritable(defaultHome)
+  }
+
+  static isPortableAtomHomePathWritable (defaultHome) {
+    let writable = false
+    let message = ''
+    try {
+      const writePermissionTestFile = path.join(this.getPortableAtomHomePath(), 'write.test')
+
+      if (!fs.existsSync(writePermissionTestFile)) {
+        fs.writeFileSync(writePermissionTestFile, 'test')
+      }
+
+      fs.removeSync(writePermissionTestFile)
+      writable = true
+    } catch (error) {
+      message = `Failed to use portable Atom home directory (${this.getPortableAtomHomePath()}). Using the default instead (${defaultHome}). ${error.message}.`
+    }
+
+    ipcMain.on('check-portable-home-writable', function (event) {
+      event.sender.send('check-portable-home-writable-response', {
+        writable: writable,
+        message: message
+      })
+    })
+
+    return writable
+  }
+}
diff --git a/src/main-process/main.coffee b/src/main-process/main.coffee
deleted file mode 100644
index 5368710aa..000000000
--- a/src/main-process/main.coffee
+++ /dev/null
@@ -1,198 +0,0 @@
-global.shellStartTime = Date.now()
-
-process.on 'uncaughtException', (error={}) ->
-  console.log(error.message) if error.message?
-  console.log(error.stack) if error.stack?
-
-{app} = require 'electron'
-fs = require 'fs-plus'
-path = require 'path'
-temp = require 'temp'
-yargs = require 'yargs'
-previousConsoleLog = console.log
-startCrashReporter = require('../crash-reporter-start')
-console.log = require 'nslog'
-
-start = ->
-  args = parseCommandLine()
-  args.env = process.env
-  setupAtomHome(args)
-  setupCompileCache()
-  if handleStartupEventWithSquirrel()
-    return
-  else if args.test and args.mainProcess
-    console.log = previousConsoleLog
-    testRunner = require(path.join(args.resourcePath, 'spec/main-process/mocha-test-runner'))
-    app.on 'ready', -> testRunner(args.pathsToOpen)
-    return
-
-  # NB: This prevents Win10 from showing dupe items in the taskbar
-  app.setAppUserModelId('com.squirrel.atom.atom')
-
-  addPathToOpen = (event, pathToOpen) ->
-    event.preventDefault()
-    args.pathsToOpen.push(pathToOpen)
-
-  addUrlToOpen = (event, urlToOpen) ->
-    event.preventDefault()
-    args.urlsToOpen.push(urlToOpen)
-
-  app.on 'open-file', addPathToOpen
-  app.on 'open-url', addUrlToOpen
-  app.on 'will-finish-launching', startCrashReporter
-
-  if args.userDataDir?
-    app.setPath('userData', args.userDataDir)
-  else if args.test
-    app.setPath('userData', temp.mkdirSync('atom-test-data'))
-
-  app.on 'ready', ->
-    app.removeListener 'open-file', addPathToOpen
-    app.removeListener 'open-url', addUrlToOpen
-
-    AtomApplication = require path.join(args.resourcePath, 'src', 'main-process', 'atom-application')
-    AtomApplication.open(args)
-
-    console.log("App load time: #{Date.now() - global.shellStartTime}ms") unless args.test
-
-normalizeDriveLetterName = (filePath) ->
-  if process.platform is 'win32'
-    filePath.replace /^([a-z]):/, ([driveLetter]) -> driveLetter.toUpperCase() + ":"
-  else
-    filePath
-
-handleStartupEventWithSquirrel = ->
-  return false unless process.platform is 'win32'
-  SquirrelUpdate = require './squirrel-update'
-  squirrelCommand = process.argv[1]
-  SquirrelUpdate.handleStartupEvent(app, squirrelCommand)
-
-setupAtomHome = ({setPortable}) ->
-  return if process.env.ATOM_HOME
-
-  atomHome = path.join(app.getPath('home'), '.atom')
-  AtomPortable = require './atom-portable'
-
-  if setPortable and not AtomPortable.isPortableInstall(process.platform, process.env.ATOM_HOME, atomHome)
-    try
-      AtomPortable.setPortable(atomHome)
-    catch error
-      console.log("Failed copying portable directory '#{atomHome}' to '#{AtomPortable.getPortableAtomHomePath()}'")
-      console.log("#{error.message} #{error.stack}")
-
-  if AtomPortable.isPortableInstall(process.platform, process.env.ATOM_HOME, atomHome)
-    atomHome = AtomPortable.getPortableAtomHomePath()
-
-  try
-    atomHome = fs.realpathSync(atomHome)
-
-  process.env.ATOM_HOME = atomHome
-
-setupCompileCache = ->
-  compileCache = require('../compile-cache')
-  compileCache.setAtomHomeDirectory(process.env.ATOM_HOME)
-
-writeFullVersion = ->
-  process.stdout.write """
-    Atom    : #{app.getVersion()}
-    Electron: #{process.versions.electron}
-    Chrome  : #{process.versions.chrome}
-    Node    : #{process.versions.node}
-
-  """
-
-parseCommandLine = ->
-  version = app.getVersion()
-  options = yargs(process.argv[1..]).wrap(100)
-  options.usage """
-    Atom Editor v#{version}
-
-    Usage: atom [options] [path ...]
-
-    One or more paths to files or folders may be specified. If there is an
-    existing Atom window that contains all of the given folders, the paths
-    will be opened in that window. Otherwise, they will be opened in a new
-    window.
-
-    Environment Variables:
-
-      ATOM_DEV_RESOURCE_PATH  The path from which Atom loads source code in dev mode.
-                              Defaults to `~/github/atom`.
-
-      ATOM_HOME               The root path for all configuration files and folders.
-                              Defaults to `~/.atom`.
-  """
-  # Deprecated 1.0 API preview flag
-  options.alias('1', 'one').boolean('1').describe('1', 'This option is no longer supported.')
-  options.boolean('include-deprecated-apis').describe('include-deprecated-apis', 'This option is not currently supported.')
-  options.alias('d', 'dev').boolean('d').describe('d', 'Run in development mode.')
-  options.alias('f', 'foreground').boolean('f').describe('f', 'Keep the main process in the foreground.')
-  options.alias('h', 'help').boolean('h').describe('h', 'Print this usage message.')
-  options.alias('l', 'log-file').string('l').describe('l', 'Log all output to file.')
-  options.alias('n', 'new-window').boolean('n').describe('n', 'Open a new window.')
-  options.boolean('profile-startup').describe('profile-startup', 'Create a profile of the startup execution time.')
-  options.alias('r', 'resource-path').string('r').describe('r', 'Set the path to the Atom source directory and enable dev-mode.')
-  options.boolean('safe').describe('safe', 'Do not load packages from ~/.atom/packages or ~/.atom/dev/packages.')
-  options.boolean('portable').describe('portable', 'Set portable mode. Copies the ~/.atom folder to be a sibling of the installed Atom location if a .atom folder is not already there.')
-  options.alias('t', 'test').boolean('t').describe('t', 'Run the specified specs and exit with error code on failures.')
-  options.alias('m', 'main-process').boolean('m').describe('m', 'Run the specified specs in the main process.')
-  options.string('timeout').describe('timeout', 'When in test mode, waits until the specified time (in minutes) and kills the process (exit code: 130).')
-  options.alias('v', 'version').boolean('v').describe('v', 'Print the version information.')
-  options.alias('w', 'wait').boolean('w').describe('w', 'Wait for window to be closed before returning.')
-  options.alias('a', 'add').boolean('a').describe('add', 'Open path as a new project in last used window.')
-  options.string('socket-path')
-  options.string('user-data-dir')
-  options.boolean('clear-window-state').describe('clear-window-state', 'Delete all Atom environment state.')
-
-  args = options.argv
-
-  if args.help
-    process.stdout.write(options.help())
-    process.exit(0)
-
-  if args.version
-    writeFullVersion()
-    process.exit(0)
-
-  addToLastWindow = args['add']
-  executedFrom = args['executed-from']?.toString() ? process.cwd()
-  devMode = args['dev']
-  safeMode = args['safe']
-  pathsToOpen = args._
-  test = args['test']
-  mainProcess = args['main-process']
-  timeout = args['timeout']
-  newWindow = args['new-window']
-  pidToKillWhenClosed = args['pid'] if args['wait']
-  logFile = args['log-file']
-  socketPath = args['socket-path']
-  userDataDir = args['user-data-dir']
-  profileStartup = args['profile-startup']
-  clearWindowState = args['clear-window-state']
-  urlsToOpen = []
-  devResourcePath = process.env.ATOM_DEV_RESOURCE_PATH ? path.join(app.getPath('home'), 'github', 'atom')
-  setPortable = args.portable
-
-  if args['resource-path']
-    devMode = true
-    resourcePath = args['resource-path']
-
-  devMode = true if test
-  resourcePath ?= devResourcePath if devMode
-
-  unless fs.statSyncNoException(resourcePath)
-    resourcePath = path.dirname(path.dirname(__dirname))
-
-  # On Yosemite the $PATH is not inherited by the "open" command, so we have to
-  # explicitly pass it by command line, see http://git.io/YC8_Ew.
-  process.env.PATH = args['path-environment'] if args['path-environment']
-
-  resourcePath = normalizeDriveLetterName(resourcePath)
-  devResourcePath = normalizeDriveLetterName(devResourcePath)
-
-  {resourcePath, devResourcePath, pathsToOpen, urlsToOpen, executedFrom, test,
-   version, pidToKillWhenClosed, devMode, safeMode, newWindow,
-   logFile, socketPath, userDataDir, profileStartup, timeout, setPortable,
-   clearWindowState, addToLastWindow, mainProcess}
-
-start()
diff --git a/src/main-process/main.js b/src/main-process/main.js
new file mode 100644
index 000000000..432f73832
--- /dev/null
+++ b/src/main-process/main.js
@@ -0,0 +1,263 @@
+global.shellStartTime = Date.now()
+
+process.on('uncaughtException', function (error = {}) {
+  if (error.message != null) {
+    console.log(error.message)
+  }
+
+  if (error.stack != null) {
+    console.log(error.stack)
+  }
+})
+
+const {app} = require('electron')
+const fs = require('fs-plus')
+const path = require('path')
+const temp = require('temp')
+const yargs = require('yargs')
+const dedent = require('dedent')
+const startCrashReporter = require('../crash-reporter-start')
+const previousConsoleLog = console.log
+console.log = require('nslog')
+
+function start () {
+  const args = parseCommandLine()
+  args.env = process.env
+  setupAtomHome(args)
+  setupCompileCache()
+
+  if (handleStartupEventWithSquirrel()) {
+    return
+  } else if (args.test && args.mainProcess) {
+    console.log = previousConsoleLog
+    app.on('ready', function () {
+      const testRunner = require(path.join(args.resourcePath, 'spec/main-process/mocha-test-runner'))
+      testRunner(args.pathsToOpen)
+    })
+    return
+  }
+
+  // NB: This prevents Win10 from showing dupe items in the taskbar
+  app.setAppUserModelId('com.squirrel.atom.atom')
+
+  function addPathToOpen (event, pathToOpen) {
+    event.preventDefault()
+    args.pathsToOpen.push(pathToOpen)
+  }
+
+  function addUrlToOpen (event, urlToOpen) {
+    event.preventDefault()
+    args.urlsToOpen.push(urlToOpen)
+  }
+
+  app.on('open-file', addPathToOpen)
+  app.on('open-url', addUrlToOpen)
+  app.on('will-finish-launching', startCrashReporter)
+
+  if (args.userDataDir != null) {
+    app.setPath('userData', args.userDataDir)
+  } else if (args.test) {
+    app.setPath('userData', temp.mkdirSync('atom-test-data'))
+  }
+
+  app.on('ready', function () {
+    app.removeListener('open-file', addPathToOpen)
+    app.removeListener('open-url', addUrlToOpen)
+    const AtomApplication = require(path.join(args.resourcePath, 'src', 'main-process', 'atom-application'))
+    AtomApplication.open(args)
+
+    if (!args.test) {
+      console.log(`App load time: ${Date.now() - global.shellStartTime}ms`)
+    }
+  })
+}
+
+function normalizeDriveLetterName (filePath) {
+  if (process.platform === 'win32') {
+    return filePath.replace(/^([a-z]):/, ([driveLetter]) => driveLetter.toUpperCase() + ':')
+  } else {
+    return filePath
+  }
+}
+
+function handleStartupEventWithSquirrel () {
+  if (process.platform !== 'win32') {
+    return false
+  }
+
+  const SquirrelUpdate = require('./squirrel-update')
+  const squirrelCommand = process.argv[1]
+  return SquirrelUpdate.handleStartupEvent(app, squirrelCommand)
+}
+
+function setupAtomHome ({setPortable}) {
+  if (process.env.ATOM_HOME) {
+    return
+  }
+
+  let atomHome = path.join(app.getPath('home'), '.atom')
+  const AtomPortable = require('./atom-portable')
+
+  if (setPortable && !AtomPortable.isPortableInstall(process.platform, process.env.ATOM_HOME, atomHome)) {
+    try {
+      AtomPortable.setPortable(atomHome)
+    } catch (error) {
+      console.log(`Failed copying portable directory '${atomHome}' to '${AtomPortable.getPortableAtomHomePath()}'`)
+      console.log(`${error.message} ${error.stack}`)
+    }
+  }
+
+  if (AtomPortable.isPortableInstall(process.platform, process.env.ATOM_HOME, atomHome)) {
+    atomHome = AtomPortable.getPortableAtomHomePath()
+  }
+
+  try {
+    atomHome = fs.realpathSync(atomHome)
+  } finally {
+    process.env.ATOM_HOME = atomHome
+  }
+}
+
+function setupCompileCache () {
+  const CompileCache = require('../compile-cache')
+  CompileCache.setAtomHomeDirectory(process.env.ATOM_HOME)
+}
+
+function writeFullVersion () {
+  process.stdout.write(
+    `Atom    : ${app.getVersion()}\n` +
+    `Electron: ${process.versions.electron}\n` +
+    `Chrome  : ${process.versions.chrome}\n` +
+    `Node    : ${process.versions.node}\n`
+  )
+}
+
+function parseCommandLine () {
+  const options = yargs(process.argv.slice(1)).wrap(100)
+  const version = app.getVersion()
+  options.usage(
+    dedent`Atom Editor v${version}
+
+    Usage: atom [options] [path ...]
+
+    One or more paths to files or folders may be specified. If there is an
+    existing Atom window that contains all of the given folders, the paths
+    will be opened in that window. Otherwise, they will be opened in a new
+    window.
+
+    Environment Variables:
+
+      ATOM_DEV_RESOURCE_PATH  The path from which Atom loads source code in dev mode.
+                              Defaults to \`~/github/atom\`.
+
+      ATOM_HOME               The root path for all configuration files and folders.
+                              Defaults to \`~/.atom\`.`
+  )
+  // Deprecated 1.0 API preview flag
+  options.alias('1', 'one').boolean('1').describe('1', 'This option is no longer supported.')
+  options.boolean('include-deprecated-apis').describe('include-deprecated-apis', 'This option is not currently supported.')
+  options.alias('d', 'dev').boolean('d').describe('d', 'Run in development mode.')
+  options.alias('f', 'foreground').boolean('f').describe('f', 'Keep the main process in the foreground.')
+  options.alias('h', 'help').boolean('h').describe('h', 'Print this usage message.')
+  options.alias('l', 'log-file').string('l').describe('l', 'Log all output to file.')
+  options.alias('n', 'new-window').boolean('n').describe('n', 'Open a new window.')
+  options.boolean('profile-startup').describe('profile-startup', 'Create a profile of the startup execution time.')
+  options.alias('r', 'resource-path').string('r').describe('r', 'Set the path to the Atom source directory and enable dev-mode.')
+  options.boolean('safe').describe(
+    'safe',
+    'Do not load packages from ~/.atom/packages or ~/.atom/dev/packages.'
+  )
+  options.boolean('portable').describe(
+    'portable',
+    'Set portable mode. Copies the ~/.atom folder to be a sibling of the installed Atom location if a .atom folder is not already there.'
+  )
+  options.alias('t', 'test').boolean('t').describe('t', 'Run the specified specs and exit with error code on failures.')
+  options.alias('m', 'main-process').boolean('m').describe('m', 'Run the specified specs in the main process.')
+  options.string('timeout').describe(
+    'timeout',
+    'When in test mode, waits until the specified time (in minutes) and kills the process (exit code: 130).'
+  )
+  options.alias('v', 'version').boolean('v').describe('v', 'Print the version information.')
+  options.alias('w', 'wait').boolean('w').describe('w', 'Wait for window to be closed before returning.')
+  options.alias('a', 'add').boolean('a').describe('add', 'Open path as a new project in last used window.')
+  options.string('socket-path')
+  options.string('user-data-dir')
+  options.boolean('clear-window-state').describe('clear-window-state', 'Delete all Atom environment state.')
+
+  const args = options.argv
+
+  if (args.help) {
+    process.stdout.write(options.help())
+    process.exit(0)
+  }
+
+  if (args.version) {
+    writeFullVersion()
+    process.exit(0)
+  }
+
+  const addToLastWindow = args['add']
+  const safeMode = args['safe']
+  const pathsToOpen = args._
+  const test = args['test']
+  const mainProcess = args['main-process']
+  const timeout = args['timeout']
+  const newWindow = args['new-window']
+  let executedFrom = null
+  if (args['executed-from'] && args['executed-from'].toString()) {
+    executedFrom = args['executed-from'].toString()
+  } else {
+    executedFrom = process.cwd()
+  }
+
+  let pidToKillWhenClosed = null
+  if (args['wait']) {
+    pidToKillWhenClosed = args['pid']
+  }
+
+  const logFile = args['log-file']
+  const socketPath = args['socket-path']
+  const userDataDir = args['user-data-dir']
+  const profileStartup = args['profile-startup']
+  const clearWindowState = args['clear-window-state']
+  const urlsToOpen = []
+  const setPortable = args.portable
+  let devMode = args['dev']
+  let devResourcePath = process.env.ATOM_DEV_RESOURCE_PATH || path.join(app.getPath('home'), 'github', 'atom')
+  let resourcePath = null
+
+  if (args['resource-path']) {
+    devMode = true
+    resourcePath = args['resource-path']
+  }
+
+  if (test) {
+    devMode = true
+  }
+
+  if (devMode && !resourcePath) {
+    resourcePath = devResourcePath
+  }
+
+  if (!fs.statSyncNoException(resourcePath)) {
+    resourcePath = path.dirname(path.dirname(__dirname))
+  }
+
+  if (args['path-environment']) {
+    // On Yosemite the $PATH is not inherited by the "open" command, so we have to
+    // explicitly pass it by command line, see http://git.io/YC8_Ew.
+    process.env.PATH = args['path-environment']
+  }
+
+  resourcePath = normalizeDriveLetterName(resourcePath)
+  devResourcePath = normalizeDriveLetterName(devResourcePath)
+
+  return {
+    resourcePath, devResourcePath, pathsToOpen, urlsToOpen, executedFrom, test,
+    version, pidToKillWhenClosed, devMode, safeMode, newWindow, logFile, socketPath,
+    userDataDir, profileStartup, timeout, setPortable, clearWindowState,
+    addToLastWindow, mainProcess
+  }
+}
+
+start()
diff --git a/src/main-process/squirrel-update.coffee b/src/main-process/squirrel-update.coffee
index a1bfc5359..acac81457 100644
--- a/src/main-process/squirrel-update.coffee
+++ b/src/main-process/squirrel-update.coffee
@@ -1,7 +1,7 @@
 fs = require 'fs-plus'
 path = require 'path'
 Spawner = require './spawner'
-WinRegistry = require './win-registry'
+WinShell = require './win-shell'
 WinPowerShell = require './win-powershell'
 
 appFolder = path.resolve(process.execPath, '..')
@@ -125,26 +125,36 @@ exports.restartAtom = (app) ->
   app.once 'will-quit', -> Spawner.spawn(path.join(binFolder, 'atom.cmd'), args)
   app.quit()
 
+updateContextMenus = (callback) ->
+  WinShell.fileContextMenu.update ->
+    WinShell.folderContextMenu.update ->
+      WinShell.folderBackgroundContextMenu.update ->
+        callback()
+
 # Handle squirrel events denoted by --squirrel-* command line arguments.
 exports.handleStartupEvent = (app, squirrelCommand) ->
   switch squirrelCommand
     when '--squirrel-install'
       createShortcuts ->
-        WinRegistry.installContextMenu ->
-          addCommandsToPath ->
-            app.quit()
+        addCommandsToPath ->
+          WinShell.fileHandler.register ->
+            updateContextMenus ->
+              app.quit()
       true
     when '--squirrel-updated'
       updateShortcuts ->
-        WinRegistry.installContextMenu ->
-          addCommandsToPath ->
+        addCommandsToPath ->
+          updateContextMenus ->
             app.quit()
       true
     when '--squirrel-uninstall'
       removeShortcuts ->
-        WinRegistry.uninstallContextMenu ->
-          removeCommandsFromPath ->
-            app.quit()
+        removeCommandsFromPath ->
+          WinShell.fileHandler.deregister ->
+            WinShell.fileContextMenu.deregister ->
+              WinShell.folderContextMenu.deregister ->
+                WinShell.folderBackgroundContextMenu.deregister ->
+                  app.quit()
       true
     when '--squirrel-obsolete'
       app.quit()
diff --git a/src/main-process/win-registry.coffee b/src/main-process/win-registry.coffee
deleted file mode 100644
index f4b81b377..000000000
--- a/src/main-process/win-registry.coffee
+++ /dev/null
@@ -1,62 +0,0 @@
-path = require 'path'
-Spawner = require './spawner'
-
-if process.env.SystemRoot
-  system32Path = path.join(process.env.SystemRoot, 'System32')
-  regPath = path.join(system32Path, 'reg.exe')
-else
-  regPath = 'reg.exe'
-
-# Registry keys used for context menu
-fileKeyPath = 'HKCU\\Software\\Classes\\*\\shell\\Atom'
-directoryKeyPath = 'HKCU\\Software\\Classes\\directory\\shell\\Atom'
-backgroundKeyPath = 'HKCU\\Software\\Classes\\directory\\background\\shell\\Atom'
-applicationsKeyPath = 'HKCU\\Software\\Classes\\Applications\\atom.exe'
-
-# Spawn reg.exe and callback when it completes
-spawnReg = (args, callback) ->
-  Spawner.spawn(regPath, args, callback)
-
-# Install the Open with Atom explorer context menu items via the registry.
-#
-# * `callback` The {Function} to call after registry operation is done.
-#   It will be invoked with the same arguments provided by {Spawner.spawn}.
-#
-# Returns `undefined`.
-exports.installContextMenu = (callback) ->
-  addToRegistry = (args, callback) ->
-    args.unshift('add')
-    args.push('/f')
-    spawnReg(args, callback)
-
-  installFileHandler = (callback) ->
-    args = ["#{applicationsKeyPath}\\shell\\open\\command", '/ve', '/d', "\"#{process.execPath}\" \"%1\""]
-    addToRegistry(args, callback)
-
-  installMenu = (keyPath, arg, callback) ->
-    args = [keyPath, '/ve', '/d', 'Open with Atom']
-    addToRegistry args, ->
-      args = [keyPath, '/v', 'Icon', '/d', "\"#{process.execPath}\""]
-      addToRegistry args, ->
-        args = ["#{keyPath}\\command", '/ve', '/d', "\"#{process.execPath}\" \"#{arg}\""]
-        addToRegistry(args, callback)
-
-  installMenu fileKeyPath, '%1', ->
-    installMenu directoryKeyPath, '%1', ->
-      installMenu backgroundKeyPath, '%V', ->
-        installFileHandler(callback)
-
-# Uninstall the Open with Atom explorer context menu items via the registry.
-#
-# * `callback` The {Function} to call after registry operation is done.
-#   It will be invoked with the same arguments provided by {Spawner.spawn}.
-#
-# Returns `undefined`.
-exports.uninstallContextMenu = (callback) ->
-  deleteFromRegistry = (keyPath, callback) ->
-    spawnReg(['delete', keyPath, '/f'], callback)
-
-  deleteFromRegistry fileKeyPath, ->
-    deleteFromRegistry directoryKeyPath, ->
-      deleteFromRegistry backgroundKeyPath, ->
-        deleteFromRegistry(applicationsKeyPath, callback)
diff --git a/src/main-process/win-shell.coffee b/src/main-process/win-shell.coffee
new file mode 100644
index 000000000..39e9f4ed0
--- /dev/null
+++ b/src/main-process/win-shell.coffee
@@ -0,0 +1,57 @@
+Registry = require 'winreg'
+Path = require 'path'
+
+exeName = Path.basename(process.execPath)
+appPath = "\"#{process.execPath}\""
+appName = exeName.replace('atom', 'Atom').replace('beta', 'Beta').replace('.exe', '')
+
+class ShellOption
+  constructor: (key, parts) ->
+    @key = key
+    @parts = parts
+
+  isRegistered: (callback) =>
+    new Registry({hive: 'HKCU', key: "#{@key}\\#{@parts[0].key}"})
+      .get @parts[0].name, (err, val) =>
+        callback(not err? and val.value is @parts[0].value)
+
+  register: (callback) =>
+    doneCount = @parts.length
+    for part in @parts
+      reg = new Registry({hive: 'HKCU', key: if part.key? then "#{@key}\\#{part.key}" else @key})
+      reg.create( -> reg.set part.name, Registry.REG_SZ, part.value, -> callback() if --doneCount is 0)
+
+  deregister: (callback) =>
+    @isRegistered (isRegistered) =>
+      if isRegistered
+        new Registry({hive: 'HKCU', key: @key}).destroy -> callback null, true
+      else
+        callback null, false
+
+  update: (callback) =>
+    new Registry({hive: 'HKCU', key: "#{@key}\\#{@parts[0].key}"})
+      .get @parts[0].name, (err, val) =>
+        if err? or not val.value.includes '\\' + exeName
+          callback(err)
+        else
+          @register callback
+
+exports.appName = appName
+
+exports.fileHandler = new ShellOption("\\Software\\Classes\\Applications\\#{exeName}",
+  [{key: 'shell\\open\\command', name: '', value: "#{appPath} \"%1\""}]
+)
+
+contextParts = [
+    {key: 'command', name: '', value: "#{appPath} \"%1\""},
+    {name: '', value: "Open with #{appName}"},
+    {name: 'Icon', value: "#{appPath}"}
+]
+
+exports.fileContextMenu = new ShellOption("\\Software\\Classes\\*\\shell\\#{appName}", contextParts)
+
+exports.folderContextMenu = new ShellOption("\\Software\\Classes\\Directory\\shell\\#{appName}", contextParts)
+
+exports.folderBackgroundContextMenu = new ShellOption("\\Software\\Classes\\Directory\\background\\shell\\#{appName}",
+  JSON.parse(JSON.stringify(contextParts).replace('%1', '%V'))
+)
diff --git a/src/package.coffee b/src/package.coffee
index b27e3ce0e..1bb8a939c 100644
--- a/src/package.coffee
+++ b/src/package.coffee
@@ -159,6 +159,7 @@ class Package
 
   # TODO: Remove. Settings view calls this method currently.
   activateConfig: ->
+    return if @configSchemaRegisteredOnLoad
     @requireMainModule()
     @registerConfigSchemaFromMainModule()
 
diff --git a/src/text-editor-component.coffee b/src/text-editor-component.coffee
index d91d3983e..a8ed9b6c1 100644
--- a/src/text-editor-component.coffee
+++ b/src/text-editor-component.coffee
@@ -344,7 +344,12 @@ class TextEditorComponent
 
   onTextInput: (event) =>
     event.stopPropagation()
-    event.preventDefault()
+
+    # WARNING: If we call preventDefault on the input of a space character,
+    # then the browser interprets the spacebar keypress as a page-down command,
+    # causing spaces to scroll elements containing editors. This is impossible
+    # to test.
+    event.preventDefault() if event.data isnt ' '
 
     return unless @isInputEnabled()