diff --git a/js/modules/backup.js b/js/modules/backup.js
index 5f7984953..9a7690394 100644
--- a/js/modules/backup.js
+++ b/js/modules/backup.js
@@ -2,7 +2,6 @@
 /* global dcodeIO: false */
 /* global _: false */
 /* global textsecure: false */
-/* global moment: false */
 /* global i18n: false */
 
 /* eslint-env browser */
@@ -13,6 +12,11 @@
 const fs = require('fs');
 const path = require('path');
 
+const tmp = require('tmp');
+const decompress = require('decompress');
+const pify = require('pify');
+const archiver = require('archiver');
+const rimraf = require('rimraf');
 const electronRemote = require('electron').remote;
 
 const {
@@ -23,13 +27,13 @@ const {
 
 module.exports = {
   getDirectoryForExport,
-  exportToDirectory,
+  backupToDirectory,
   getDirectoryForImport,
   importFromDirectory,
   // for testing
   sanitizeFileName,
   trimFileName,
-  getAttachmentFileName,
+  getExportAttachmentFileName,
   getConversationDirName,
   getConversationLoggingName,
 };
@@ -102,12 +106,12 @@ function createOutputStream(writer) {
   };
 }
 
-async function exportNonMessages(db, parent) {
+async function exportContactAndGroupsToFile(db, parent) {
   const writer = await createFileAndWriter(parent, 'db.json');
-  return exportToJsonFile(db, writer);
+  return exportContactsAndGroups(db, writer);
 }
 
-function exportToJsonFile(db, fileWriter) {
+function exportContactsAndGroups(db, fileWriter) {
   return new Promise((resolve, reject) => {
     let storeNames = db.objectStoreNames;
     storeNames = _.without(
@@ -347,12 +351,18 @@ function createDirectory(parent, name) {
   return new Promise((resolve, reject) => {
     const sanitized = sanitizeFileName(name);
     const targetDir = path.join(parent, sanitized);
+    if (fs.existsSync(targetDir)) {
+      resolve(targetDir);
+      return;
+    }
+
     fs.mkdir(targetDir, (error) => {
       if (error) {
-        return reject(error);
+        reject(error);
+        return;
       }
 
-      return resolve(targetDir);
+      resolve(targetDir);
     });
   });
 }
@@ -381,9 +391,8 @@ function readFileAsText(parent, name) {
   });
 }
 
-function readFileAsArrayBuffer(parent, name) {
+function readFileAsArrayBuffer(targetPath) {
   return new Promise((resolve, reject) => {
-    const targetPath = path.join(parent, name);
     // omitting the encoding to get a buffer back
     fs.readFile(targetPath, (error, buffer) => {
       if (error) {
@@ -413,7 +422,7 @@ function trimFileName(filename) {
 }
 
 
-function getAttachmentFileName(attachment) {
+function getExportAttachmentFileName(message, index, attachment) {
   if (attachment.fileName) {
     return trimFileName(attachment.fileName);
   }
@@ -428,25 +437,44 @@ function getAttachmentFileName(attachment) {
   return name;
 }
 
-async function readAttachment(parent, message, attachment) {
-  const name = getAttachmentFileName(attachment);
-  const sanitized = sanitizeFileName(name);
-  const attachmentDir = path.join(parent, message.received_at.toString());
+function getAnonymousAttachmentFileName(message, index) {
+  if (!index) {
+    return message.id;
+  }
+  return `${message.id}-${index}`;
+}
+
+async function readAttachment(dir, attachment, name) {
+  const anonymousName = sanitizeFileName(name);
+  const targetPath = path.join(dir, anonymousName);
 
-  attachment.data = await readFileAsArrayBuffer(attachmentDir, sanitized);
+  if (!fs.existsSync(targetPath)) {
+    console.log(`Warning: attachment ${anonymousName} not found`);
+    return;
+  }
+
+  attachment.data = await readFileAsArrayBuffer(targetPath);
 }
 
-async function writeAttachment(dir, attachment) {
-  const filename = getAttachmentFileName(attachment);
+async function writeAttachment(dir, message, index, attachment) {
+  const filename = getAnonymousAttachmentFileName(message, index);
+  const target = path.join(dir, filename);
+  if (fs.existsSync(target)) {
+    console.log(`Skipping attachment ${filename}; already exists`);
+    return;
+  }
+
   const writer = await createFileAndWriter(dir, filename);
   const stream = createOutputStream(writer);
   stream.write(Buffer.from(attachment.data));
-  return stream.close();
+  await stream.close();
 }
 
-async function writeAttachments(parentDir, name, messageId, attachments) {
-  const dir = await createDirectory(parentDir, messageId);
-  const promises = _.map(attachments, attachment => writeAttachment(dir, attachment));
+async function writeAttachments(dir, name, message, attachments) {
+  const promises = _.map(
+    attachments,
+    (attachment, index) => writeAttachment(dir, message, index, attachment)
+  );
   try {
     await Promise.all(promises);
   } catch (error) {
@@ -464,10 +492,27 @@ function sanitizeFileName(filename) {
   return filename.toString().replace(/[^a-z0-9.,+()'#\- ]/gi, '_');
 }
 
-async function exportConversation(db, name, conversation, dir) {
+async function exportConversation(db, conversation, options) {
+  options = options || {};
+  const {
+    name,
+    dir,
+    attachmentsDir,
+  } = options;
+  if (!name) {
+    throw new Error('Need a name!');
+  }
+  if (!dir) {
+    throw new Error('Need a target directory!');
+  }
+  if (!attachmentsDir) {
+    throw new Error('Need an attachments directory!');
+  }
+
   console.log('exporting conversation', name);
   const writer = await createFileAndWriter(dir, 'messages.json');
-  return new Promise((resolve, reject) => {
+
+  return new Promise(async (resolve, reject) => {
     const transaction = db.transaction('messages', 'readwrite');
     transaction.onerror = () => {
       Whisper.Database.handleDOMException(
@@ -505,7 +550,6 @@ async function exportConversation(db, name, conversation, dir) {
       const cursor = event.target.result;
       if (cursor) {
         const message = cursor.value;
-        const messageId = message.received_at;
         const { attachments } = message;
 
         // skip message if it is disappearing, no matter the amount of time left
@@ -539,9 +583,11 @@ async function exportConversation(db, name, conversation, dir) {
         stream.write(jsonString);
 
         if (attachments && attachments.length) {
-          const process = () => writeAttachments(dir, name, messageId, attachments);
+          const exportAttachments = () =>
+            writeAttachments(attachmentsDir, name, message, attachments);
+
           // eslint-disable-next-line more/no-then
-          promiseChain = promiseChain.then(process);
+          promiseChain = promiseChain.then(exportAttachments);
         }
 
         count += 1;
@@ -598,7 +644,20 @@ function getConversationLoggingName(conversation) {
   return name;
 }
 
-function exportConversations(db, parentDir) {
+function exportConversations(db, options) {
+  options = options || {};
+  const {
+    messagesDir,
+    attachmentsDir,
+  } = options;
+
+  if (!messagesDir) {
+    return Promise.reject(new Error('Need a messages directory!'));
+  }
+  if (!attachmentsDir) {
+    return Promise.reject(new Error('Need an attachments directory!'));
+  }
+
   return new Promise((resolve, reject) => {
     const transaction = db.transaction('conversations', 'readwrite');
     transaction.onerror = () => {
@@ -630,8 +689,12 @@ function exportConversations(db, parentDir) {
         const name = getConversationLoggingName(conversation);
 
         const process = async () => {
-          const dir = await createDirectory(parentDir, dirName);
-          return exportConversation(db, name, conversation, dir);
+          const dir = await createDirectory(messagesDir, dirName);
+          return exportConversation(db, conversation, {
+            name,
+            dir,
+            attachmentsDir,
+          });
         };
 
         console.log('scheduling export for conversation', name);
@@ -688,12 +751,11 @@ function getDirContents(dir) {
   });
 }
 
-function loadAttachments(dir, message) {
-  const promises = _.map(message.attachments, attachment => readAttachment(
-    dir,
-    message,
-    attachment
-  ));
+function loadAttachments(dir, message, getName) {
+  const promises = _.map(message.attachments, (attachment, index) => {
+    const name = getName(message, index, attachment);
+    return readAttachment(dir, attachment, name);
+  });
   return Promise.all(promises);
 }
 
@@ -765,7 +827,11 @@ async function importConversation(db, dir, options) {
   options = options || {};
   _.defaults(options, { messageLookup: {} });
 
-  const { messageLookup } = options;
+  const {
+    messageLookup,
+    attachmentsDir,
+  } = options;
+
   let conversationId = 'unknown';
   let total = 0;
   let skipped = 0;
@@ -794,13 +860,18 @@ async function importConversation(db, dir, options) {
     }
 
     if (message.attachments && message.attachments.length) {
-      const process = async () => {
-        await loadAttachments(dir, message);
+      const importMessage = async () => {
+        const getName = attachmentsDir
+          ? getAnonymousAttachmentFileName
+          : getExportAttachmentFileName;
+        const parent = attachmentsDir || path.join(dir, message.received_at.toString());
+
+        await loadAttachments(parent, message, getName);
         return saveMessage(db, message);
       };
 
       // eslint-disable-next-line more/no-then
-      promiseChain = promiseChain.then(process);
+      promiseChain = promiseChain.then(importMessage);
 
       return false;
     }
@@ -825,7 +896,6 @@ async function importConversation(db, dir, options) {
 
 async function importConversations(db, dir, options) {
   const contents = await getDirContents(dir);
-
   let promiseChain = Promise.resolve();
 
   _.forEach(contents, (conversationDir) => {
@@ -833,10 +903,10 @@ async function importConversations(db, dir, options) {
       return;
     }
 
-    const process = () => importConversation(db, conversationDir, options);
+    const loadConversation = () => importConversation(db, conversationDir, options);
 
     // eslint-disable-next-line more/no-then
-    promiseChain = promiseChain.then(process);
+    promiseChain = promiseChain.then(loadConversation);
   });
 
   return promiseChain;
@@ -908,10 +978,6 @@ function assembleLookup(db, storeName, keyFunction) {
   });
 }
 
-function getTimestamp() {
-  return moment().format('YYYY MMM Do [at] h.mm.ss a');
-}
-
 function getDirectoryForExport() {
   const options = {
     title: i18n('exportChooserTitle'),
@@ -920,22 +986,72 @@ function getDirectoryForExport() {
   return getDirectory(options);
 }
 
-async function exportToDirectory(directory) {
-  const name = `Signal Export ${getTimestamp()}`;
+function createZip(zipDir, targetDir) {
+  return new Promise((resolve, reject) => {
+    const target = path.join(zipDir, 'messages.zip');
+    const output = fs.createWriteStream(target);
+    const archive = archiver('zip', {
+      cwd: targetDir,
+    });
+
+    output.on('close', () => {
+      resolve(target);
+    });
+
+    archive.on('warning', (error) => {
+      console.log(`Archive generation warning: ${error.stack}`);
+    });
+    archive.on('error', reject);
+
+    archive.pipe(output);
+
+    archive.directory(targetDir, '');
+
+    archive.finalize();
+  });
+}
+
+function createTempDir() {
+  return pify(tmp.dir)();
+}
+
+function deleteAll(pattern) {
+  console.log(`Deleting ${pattern}`);
+  return pify(rimraf)(pattern);
+}
+
+async function backupToDirectory(directory) {
+  let tempDir;
   try {
+    tempDir = await createTempDir();
+
     const db = await Whisper.Database.open();
-    const dir = await createDirectory(directory, name);
-    await exportNonMessages(db, dir);
-    await exportConversations(db, dir);
+    const attachmentsDir = await createDirectory(directory, 'attachments');
+
+    await exportContactAndGroupsToFile(db, tempDir);
+    await exportConversations(db, {
+      messagesDir: tempDir,
+      attachmentsDir,
+    });
+
+    await createZip(directory, tempDir);
+
+    // now that we've made the zip file, we can delete the temp messages directory
+    await deleteAll(tempDir);
+    tempDir = null;
 
     console.log('done backing up!');
-    return dir;
+    return directory;
   } catch (error) {
     console.log(
       'the backup went wrong:',
       error && error.stack ? error.stack : error
     );
     throw error;
+  } finally {
+    if (tempDir) {
+      await deleteAll(tempDir);
+    }
   }
 }
 
@@ -964,9 +1080,35 @@ async function importFromDirectory(directory, options) {
       groupLookup,
     });
 
+    const zipPath = path.join(directory, 'messages.zip');
+    if (fs.existsSync(zipPath)) {
+      // we're in the world of an encrypted, zipped backup
+      let tempDir;
+      try {
+        tempDir = await createTempDir();
+        const attachmentsDir = path.join(directory, 'attachments');
+
+        await decompress(zipPath, tempDir);
+
+        options = Object.assign({}, options, {
+          attachmentsDir,
+        });
+        const result = await importNonMessages(db, tempDir, options);
+        await importConversations(db, tempDir, options);
+
+        console.log('done importing from backup!');
+        return result;
+      } finally {
+        if (tempDir) {
+          await deleteAll(tempDir);
+        }
+      }
+    }
+
     const result = await importNonMessages(db, directory, options);
     await importConversations(db, directory, options);
-    console.log('done restoring from backup!');
+
+    console.log('done importing!');
     return result;
   } catch (error) {
     console.log(
diff --git a/package.json b/package.json
index 37eee2dbc..9b7675f9c 100644
--- a/package.json
+++ b/package.json
@@ -44,11 +44,13 @@
     "open-coverage": "open coverage/lcov-report/index.html"
   },
   "dependencies": {
+    "archiver": "^2.1.1",
     "blob-util": "^1.3.0",
     "blueimp-canvas-to-blob": "^3.14.0",
     "blueimp-load-image": "^2.18.0",
     "bunyan": "^1.8.12",
     "config": "^1.28.1",
+    "decompress": "^4.2.0",
     "electron-config": "^1.0.0",
     "electron-editor-context-menu": "^1.1.1",
     "electron-is-dev": "^0.3.0",
@@ -67,12 +69,14 @@
     "node-fetch": "https://github.com/scottnonnenberg/node-fetch.git#3e5f51e08c647ee5f20c43b15cf2d352d61c36b4",
     "node-notifier": "^5.1.2",
     "os-locale": "^2.1.0",
+    "pify": "^3.0.0",
     "proxy-agent": "^2.1.0",
     "read-last-lines": "^1.3.0",
     "rimraf": "^2.6.2",
     "semver": "^5.4.1",
     "spellchecker": "^3.4.4",
     "testcheck": "^1.0.0-rc.2",
+    "tmp": "^0.0.33",
     "websocket": "^1.0.25"
   },
   "devDependencies": {
@@ -105,8 +109,7 @@
     "nsp": "^3.2.1",
     "nyc": "^11.4.1",
     "sinon": "^4.4.2",
-    "spectron": "^3.8.0",
-    "tmp": "^0.0.33"
+    "spectron": "^3.8.0"
   },
   "engines": {
     "node": "8.2.1"
diff --git a/test/backup_test.js b/test/backup_test.js
index 87dd31567..e1fc49266 100644
--- a/test/backup_test.js
+++ b/test/backup_test.js
@@ -35,13 +35,13 @@ describe('Backup', function() {
     });
   });
 
-  describe('getAttachmentFileName', function() {
+  describe('getExportAttachmentFileName', function() {
     it('uses original filename if attachment has one', function() {
       var attachment = {
         fileName: 'blah.jpg'
       };
       var expected = 'blah.jpg';
-      assert.strictEqual(Signal.Backup.getAttachmentFileName(attachment), expected);
+      assert.strictEqual(Signal.Backup.getExportAttachmentFileName(attachment), expected);
     });
 
     it('uses attachment id if no filename', function() {
@@ -49,7 +49,7 @@ describe('Backup', function() {
         id: '123'
       };
       var expected = '123';
-      assert.strictEqual(Signal.Backup.getAttachmentFileName(attachment), expected);
+      assert.strictEqual(Signal.Backup.getExportAttachmentFileName(attachment), expected);
     });
 
     it('uses filename and contentType if available', function() {
@@ -58,7 +58,7 @@ describe('Backup', function() {
         contentType: 'image/jpeg'
       };
       var expected = '123.jpeg';
-      assert.strictEqual(Signal.Backup.getAttachmentFileName(attachment), expected);
+      assert.strictEqual(Signal.Backup.getExportAttachmentFileName(attachment), expected);
     });
 
     it('handles strange contentType', function() {
@@ -67,7 +67,7 @@ describe('Backup', function() {
         contentType: 'something'
       };
       var expected = '123.something';
-      assert.strictEqual(Signal.Backup.getAttachmentFileName(attachment), expected);
+      assert.strictEqual(Signal.Backup.getExportAttachmentFileName(attachment), expected);
     });
   });
 
diff --git a/yarn.lock b/yarn.lock
index 2e852329c..23a52f066 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -192,6 +192,19 @@ archiver-utils@^1.3.0:
     normalize-path "^2.0.0"
     readable-stream "^2.0.0"
 
+archiver@^2.1.1:
+  version "2.1.1"
+  resolved "https://registry.yarnpkg.com/archiver/-/archiver-2.1.1.tgz#ff662b4a78201494a3ee544d3a33fe7496509ebc"
+  dependencies:
+    archiver-utils "^1.3.0"
+    async "^2.0.0"
+    buffer-crc32 "^0.2.1"
+    glob "^7.0.0"
+    lodash "^4.8.0"
+    readable-stream "^2.0.0"
+    tar-stream "^1.5.0"
+    zip-stream "^1.2.0"
+
 archiver@~2.1.0:
   version "2.1.0"
   resolved "https://registry.yarnpkg.com/archiver/-/archiver-2.1.0.tgz#d2df2e8d5773a82c1dcce925ccc41450ea999afd"
@@ -443,6 +456,10 @@ balanced-match@^0.4.1:
   version "0.4.2"
   resolved "https://registry.yarnpkg.com/balanced-match/-/balanced-match-0.4.2.tgz#cb3f3e3c732dc0f01ee70b403f302e61d7709838"
 
+base64-js@0.0.8:
+  version "0.0.8"
+  resolved "https://registry.yarnpkg.com/base64-js/-/base64-js-0.0.8.tgz#1101e9544f4a76b1bc3b26d452ca96d7a35e7978"
+
 base64-js@1.2.0, base64-js@^1.0.2:
   version "1.2.0"
   resolved "https://registry.yarnpkg.com/base64-js/-/base64-js-1.2.0.tgz#a39992d723584811982be5e290bb6a53d86700f1"
@@ -581,7 +598,7 @@ browser-stdout@1.3.0:
   version "1.3.0"
   resolved "https://registry.yarnpkg.com/browser-stdout/-/browser-stdout-1.3.0.tgz#f351d32969d32fa5d7a5567154263d928ae3bd1f"
 
-buffer-crc32@^0.2.1:
+buffer-crc32@^0.2.1, buffer-crc32@~0.2.3:
   version "0.2.13"
   resolved "https://registry.yarnpkg.com/buffer-crc32/-/buffer-crc32-0.2.13.tgz#0d333e3f00eac50aa1454abd30ef8c2a5d9a7242"
 
@@ -597,6 +614,14 @@ buffer@4.9.1:
     ieee754 "^1.1.4"
     isarray "^1.0.0"
 
+buffer@^3.0.1:
+  version "3.6.0"
+  resolved "https://registry.yarnpkg.com/buffer/-/buffer-3.6.0.tgz#a72c936f77b96bf52f5f7e7b467180628551defb"
+  dependencies:
+    base64-js "0.0.8"
+    ieee754 "^1.1.4"
+    isarray "^1.0.0"
+
 buffers@~0.1.1:
   version "0.1.1"
   resolved "https://registry.yarnpkg.com/buffers/-/buffers-0.1.1.tgz#b24579c3bed4d6d396aeee6d9a8ae7f5482ab7bb"
@@ -911,6 +936,12 @@ commander@^2.9.0, commander@~2.9.0:
   dependencies:
     graceful-readlink ">= 1.0.0"
 
+commander@~2.8.1:
+  version "2.8.1"
+  resolved "https://registry.yarnpkg.com/commander/-/commander-2.8.1.tgz#06be367febfda0c330aa1e2a072d3dc9762425d4"
+  dependencies:
+    graceful-readlink ">= 1.0.0"
+
 comment-parser@^0.3.1:
   version "0.3.1"
   resolved "https://registry.yarnpkg.com/comment-parser/-/comment-parser-0.3.1.tgz#fd657aac8c1492d308c9a6100fc9b49d2435aba1"
@@ -1184,6 +1215,41 @@ decompress-response@^3.3.0:
   dependencies:
     mimic-response "^1.0.0"
 
+decompress-tar@^4.0.0, decompress-tar@^4.1.0, decompress-tar@^4.1.1:
+  version "4.1.1"
+  resolved "https://registry.yarnpkg.com/decompress-tar/-/decompress-tar-4.1.1.tgz#718cbd3fcb16209716e70a26b84e7ba4592e5af1"
+  dependencies:
+    file-type "^5.2.0"
+    is-stream "^1.1.0"
+    tar-stream "^1.5.2"
+
+decompress-tarbz2@^4.0.0:
+  version "4.1.1"
+  resolved "https://registry.yarnpkg.com/decompress-tarbz2/-/decompress-tarbz2-4.1.1.tgz#3082a5b880ea4043816349f378b56c516be1a39b"
+  dependencies:
+    decompress-tar "^4.1.0"
+    file-type "^6.1.0"
+    is-stream "^1.1.0"
+    seek-bzip "^1.0.5"
+    unbzip2-stream "^1.0.9"
+
+decompress-targz@^4.0.0:
+  version "4.1.1"
+  resolved "https://registry.yarnpkg.com/decompress-targz/-/decompress-targz-4.1.1.tgz#c09bc35c4d11f3de09f2d2da53e9de23e7ce1eee"
+  dependencies:
+    decompress-tar "^4.1.1"
+    file-type "^5.2.0"
+    is-stream "^1.1.0"
+
+decompress-unzip@^4.0.1:
+  version "4.0.1"
+  resolved "https://registry.yarnpkg.com/decompress-unzip/-/decompress-unzip-4.0.1.tgz#deaaccdfd14aeaf85578f733ae8210f9b4848f69"
+  dependencies:
+    file-type "^3.8.0"
+    get-stream "^2.2.0"
+    pify "^2.3.0"
+    yauzl "^2.4.2"
+
 decompress-zip@0.3.0:
   version "0.3.0"
   resolved "https://registry.yarnpkg.com/decompress-zip/-/decompress-zip-0.3.0.tgz#ae3bcb7e34c65879adfe77e19c30f86602b4bdb0"
@@ -1196,6 +1262,19 @@ decompress-zip@0.3.0:
     readable-stream "^1.1.8"
     touch "0.0.3"
 
+decompress@^4.2.0:
+  version "4.2.0"
+  resolved "https://registry.yarnpkg.com/decompress/-/decompress-4.2.0.tgz#7aedd85427e5a92dacfe55674a7c505e96d01f9d"
+  dependencies:
+    decompress-tar "^4.0.0"
+    decompress-tarbz2 "^4.0.0"
+    decompress-targz "^4.0.0"
+    decompress-unzip "^4.0.1"
+    graceful-fs "^4.1.10"
+    make-dir "^1.0.0"
+    pify "^2.3.0"
+    strip-dirs "^2.0.0"
+
 deep-eql@^3.0.0:
   version "3.0.1"
   resolved "https://registry.yarnpkg.com/deep-eql/-/deep-eql-3.0.1.tgz#dfc9404400ad1c8fe023e7da1df1c147c4b444df"
@@ -1931,10 +2010,18 @@ file-sync-cmp@^0.1.0:
   version "0.1.1"
   resolved "https://registry.yarnpkg.com/file-sync-cmp/-/file-sync-cmp-0.1.1.tgz#a5e7a8ffbfa493b43b923bbd4ca89a53b63b612b"
 
-file-type@^3.1.0:
+file-type@^3.1.0, file-type@^3.8.0:
   version "3.9.0"
   resolved "https://registry.yarnpkg.com/file-type/-/file-type-3.9.0.tgz#257a078384d1db8087bc449d107d52a52672b9e9"
 
+file-type@^5.2.0:
+  version "5.2.0"
+  resolved "https://registry.yarnpkg.com/file-type/-/file-type-5.2.0.tgz#2ddbea7c73ffe36368dfae49dc338c058c2b8ad6"
+
+file-type@^6.1.0:
+  version "6.2.0"
+  resolved "https://registry.yarnpkg.com/file-type/-/file-type-6.2.0.tgz#e50cd75d356ffed4e306dc4f5bcf52a79903a919"
+
 file-uri-to-path@1:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/file-uri-to-path/-/file-uri-to-path-1.0.0.tgz#553a7b8446ff6f684359c445f1e37a05dacc33dd"
@@ -2192,6 +2279,13 @@ get-stream@3.0.0, get-stream@^3.0.0:
   version "3.0.0"
   resolved "https://registry.yarnpkg.com/get-stream/-/get-stream-3.0.0.tgz#8e943d1358dc37555054ecbe2edb05aa174ede14"
 
+get-stream@^2.2.0:
+  version "2.3.1"
+  resolved "https://registry.yarnpkg.com/get-stream/-/get-stream-2.3.1.tgz#5f38f93f346009666ee0150a054167f91bdd95de"
+  dependencies:
+    object-assign "^4.0.1"
+    pinkie-promise "^2.0.0"
+
 get-uri@^2.0.0:
   version "2.0.1"
   resolved "https://registry.yarnpkg.com/get-uri/-/get-uri-2.0.1.tgz#dbdcacacd8c608a38316869368117697a1631c59"
@@ -2371,7 +2465,7 @@ got@^8.2.0:
     url-parse-lax "^3.0.0"
     url-to-options "^1.0.1"
 
-graceful-fs@^4.1.0, graceful-fs@^4.1.11, graceful-fs@^4.1.2, graceful-fs@^4.1.3, graceful-fs@^4.1.6, graceful-fs@^4.1.9:
+graceful-fs@^4.1.0, graceful-fs@^4.1.10, graceful-fs@^4.1.11, graceful-fs@^4.1.2, graceful-fs@^4.1.3, graceful-fs@^4.1.6, graceful-fs@^4.1.9:
   version "4.1.11"
   resolved "https://registry.yarnpkg.com/graceful-fs/-/graceful-fs-4.1.11.tgz#0e8bdfe4d1ddb8854d64e04ea7c00e2a026e5658"
 
@@ -2888,6 +2982,10 @@ is-installed-globally@^0.1.0:
     global-dirs "^0.1.0"
     is-path-inside "^1.0.0"
 
+is-natural-number@^4.0.1:
+  version "4.0.1"
+  resolved "https://registry.yarnpkg.com/is-natural-number/-/is-natural-number-4.0.1.tgz#ab9d76e1db4ced51e35de0c72ebecf09f734cde8"
+
 is-npm@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/is-npm/-/is-npm-1.0.0.tgz#f2fb63a65e4905b406c86072765a1a4dc793b9f4"
@@ -4757,6 +4855,12 @@ scss-tokenizer@^0.2.1:
     js-base64 "^2.1.8"
     source-map "^0.4.2"
 
+seek-bzip@^1.0.5:
+  version "1.0.5"
+  resolved "https://registry.yarnpkg.com/seek-bzip/-/seek-bzip-1.0.5.tgz#cfe917cb3d274bcffac792758af53173eb1fabdc"
+  dependencies:
+    commander "~2.8.1"
+
 semver-diff@^2.0.0:
   version "2.1.0"
   resolved "https://registry.yarnpkg.com/semver-diff/-/semver-diff-2.1.0.tgz#4bbb8437c8d37e4b0cf1a68fd726ec6d645d6d36"
@@ -5109,6 +5213,12 @@ strip-bom@^3.0.0:
   version "3.0.0"
   resolved "https://registry.yarnpkg.com/strip-bom/-/strip-bom-3.0.0.tgz#2334c18e9c759f7bdd56fdef7e9ae3d588e68ed3"
 
+strip-dirs@^2.0.0:
+  version "2.1.0"
+  resolved "https://registry.yarnpkg.com/strip-dirs/-/strip-dirs-2.1.0.tgz#4987736264fc344cf20f6c34aca9d13d1d4ed6c5"
+  dependencies:
+    is-natural-number "^4.0.1"
+
 strip-eof@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/strip-eof/-/strip-eof-1.0.0.tgz#bb43ff5598a6eb05d89b59fcd129c983313606bf"
@@ -5197,6 +5307,15 @@ tar-stream@^1.5.0:
     readable-stream "^2.0.0"
     xtend "^4.0.0"
 
+tar-stream@^1.5.2:
+  version "1.5.5"
+  resolved "https://registry.yarnpkg.com/tar-stream/-/tar-stream-1.5.5.tgz#5cad84779f45c83b1f2508d96b09d88c7218af55"
+  dependencies:
+    bl "^1.0.0"
+    end-of-stream "^1.0.0"
+    readable-stream "^2.0.0"
+    xtend "^4.0.0"
+
 tar@^2.0.0:
   version "2.2.1"
   resolved "https://registry.yarnpkg.com/tar/-/tar-2.2.1.tgz#8e4d2a256c0e2185c6b18ad694aec968b83cb1d1"
@@ -5414,6 +5533,13 @@ uglify-to-browserify@~1.0.0:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/uglify-to-browserify/-/uglify-to-browserify-1.0.2.tgz#6e0924d6bda6b5afe349e39a6d632850a0f882b7"
 
+unbzip2-stream@^1.0.9:
+  version "1.2.5"
+  resolved "https://registry.yarnpkg.com/unbzip2-stream/-/unbzip2-stream-1.2.5.tgz#73a033a567bbbde59654b193c44d48a7e4f43c47"
+  dependencies:
+    buffer "^3.0.1"
+    through "^2.3.6"
+
 underscore.string@~3.2.3:
   version "3.2.3"
   resolved "https://registry.yarnpkg.com/underscore.string/-/underscore.string-3.2.3.tgz#806992633665d5e5fcb4db1fb3a862eb68e9e6da"
@@ -5894,6 +6020,13 @@ yauzl@2.4.1:
   dependencies:
     fd-slicer "~1.0.1"
 
+yauzl@^2.4.2:
+  version "2.9.1"
+  resolved "https://registry.yarnpkg.com/yauzl/-/yauzl-2.9.1.tgz#a81981ea70a57946133883f029c5821a89359a7f"
+  dependencies:
+    buffer-crc32 "~0.2.3"
+    fd-slicer "~1.0.1"
+
 zip-stream@^1.2.0:
   version "1.2.0"
   resolved "https://registry.yarnpkg.com/zip-stream/-/zip-stream-1.2.0.tgz#a8bc45f4c1b49699c6b90198baacaacdbcd4ba04"