diff --git a/20181117-mfa-in-js/server/yarn.lock b/20181117-mfa-in-js/server/yarn.lock
index 2b094e5..5553850 100644
--- a/20181117-mfa-in-js/server/yarn.lock
+++ b/20181117-mfa-in-js/server/yarn.lock
@@ -205,9 +205,9 @@ chokidar@^2.0.2:
   optionalDependencies:
     fsevents "^1.2.2"
 
-chownr@^1.0.1:
-  version "1.0.1"
-  resolved "https://registry.yarnpkg.com/chownr/-/chownr-1.0.1.tgz#e2a75042a9551908bebd25b8523d5f9769d79181"
+chownr@^1.1.4:
+  version "1.1.4"
+  resolved "https://registry.yarnpkg.com/chownr/-/chownr-1.1.4.tgz#6fc9d7b42d32a583596337666e7d08084da2cc6b"
 
 ci-info@^1.5.0:
   version "1.5.1"
@@ -451,7 +451,7 @@ expand-brackets@^2.1.4:
 
 express@^4.16.3:
   version "4.16.3"
-  resolved "http://registry.npmjs.org/express/-/express-4.16.3.tgz#6af8a502350db3246ecc4becf6b5a34d22f7ed53"
+  resolved "https://registry.npmjs.org/express/-/express-4.16.3.tgz#6af8a502350db3246ecc4becf6b5a34d22f7ed53"
   dependencies:
     accepts "~1.3.5"
     array-flatten "1.1.1"
@@ -557,11 +557,11 @@ from@^0.1.7:
   version "0.1.7"
   resolved "https://registry.yarnpkg.com/from/-/from-0.1.7.tgz#83c60afc58b9c56997007ed1a768b3ab303a44fe"
 
-fs-minipass@^1.2.5:
-  version "1.2.5"
-  resolved "https://registry.yarnpkg.com/fs-minipass/-/fs-minipass-1.2.5.tgz#06c277218454ec288df77ada54a03b8702aacb9d"
+fs-minipass@^1.2.7:
+  version "1.2.7"
+  resolved "https://registry.yarnpkg.com/fs-minipass/-/fs-minipass-1.2.7.tgz#ccff8570841e7fe4265693da88936c55aed7f7c7"
   dependencies:
-    minipass "^2.2.1"
+    minipass "^2.6.0"
 
 fs.realpath@^1.0.0:
   version "1.0.0"
@@ -621,7 +621,7 @@ global-dirs@^0.1.0:
 
 got@^6.7.1:
   version "6.7.1"
-  resolved "http://registry.npmjs.org/got/-/got-6.7.1.tgz#240cd05785a9a18e561dc1b44b41c763ef1e8db0"
+  resolved "https://registry.npmjs.org/got/-/got-6.7.1.tgz#240cd05785a9a18e561dc1b44b41c763ef1e8db0"
   dependencies:
     create-error-class "^3.0.0"
     duplexer3 "^0.1.4"
@@ -685,7 +685,7 @@ http-errors@1.6.2:
 
 http-errors@~1.6.2:
   version "1.6.3"
-  resolved "http://registry.npmjs.org/http-errors/-/http-errors-1.6.3.tgz#8b55680bb4be283a0b5bf4ea2e38580be1d9320d"
+  resolved "https://registry.npmjs.org/http-errors/-/http-errors-1.6.3.tgz#8b55680bb4be283a0b5bf4ea2e38580be1d9320d"
   dependencies:
     depd "~1.1.2"
     inherits "2.0.3"
@@ -1009,26 +1009,26 @@ minimatch@^3.0.2, minimatch@^3.0.4:
   dependencies:
     brace-expansion "^1.1.7"
 
-minimist@0.0.8:
-  version "0.0.8"
-  resolved "http://registry.npmjs.org/minimist/-/minimist-0.0.8.tgz#857fcabfc3397d2625b8228262e86aa7a011b05d"
-
 minimist@^1.2.0:
   version "1.2.0"
-  resolved "http://registry.npmjs.org/minimist/-/minimist-1.2.0.tgz#a35008b20f41383eec1fb914f4cd5df79a264284"
+  resolved "https://registry.npmjs.org/minimist/-/minimist-1.2.0.tgz#a35008b20f41383eec1fb914f4cd5df79a264284"
 
-minipass@^2.2.1, minipass@^2.3.3:
-  version "2.3.4"
-  resolved "https://registry.yarnpkg.com/minipass/-/minipass-2.3.4.tgz#4768d7605ed6194d6d576169b9e12ef71e9d9957"
+minimist@^1.2.5:
+  version "1.2.5"
+  resolved "https://registry.yarnpkg.com/minimist/-/minimist-1.2.5.tgz#67d66014b66a6a8aaa0c083c5fd58df4e4e97602"
+
+minipass@^2.6.0, minipass@^2.9.0:
+  version "2.9.0"
+  resolved "https://registry.yarnpkg.com/minipass/-/minipass-2.9.0.tgz#e713762e7d3e32fed803115cf93e04bca9fcc9a6"
   dependencies:
     safe-buffer "^5.1.2"
     yallist "^3.0.0"
 
-minizlib@^1.1.0:
-  version "1.1.0"
-  resolved "https://registry.yarnpkg.com/minizlib/-/minizlib-1.1.0.tgz#11e13658ce46bc3a70a267aac58359d1e0c29ceb"
+minizlib@^1.3.3:
+  version "1.3.3"
+  resolved "https://registry.yarnpkg.com/minizlib/-/minizlib-1.3.3.tgz#2290de96818a34c29551c8a8d301216bd65a861d"
   dependencies:
-    minipass "^2.2.1"
+    minipass "^2.9.0"
 
 mixin-deep@^1.2.0:
   version "1.3.1"
@@ -1037,11 +1037,11 @@ mixin-deep@^1.2.0:
     for-in "^1.0.2"
     is-extendable "^1.0.1"
 
-mkdirp@^0.5.0, mkdirp@^0.5.1:
-  version "0.5.1"
-  resolved "http://registry.npmjs.org/mkdirp/-/mkdirp-0.5.1.tgz#30057438eac6cf7f8c4767f38648d6697d75c903"
+mkdirp@^0.5.1, mkdirp@^0.5.5:
+  version "0.5.5"
+  resolved "https://registry.yarnpkg.com/mkdirp/-/mkdirp-0.5.5.tgz#d91cefd62d1436ca0f41620e251288d420099def"
   dependencies:
-    minimist "0.0.8"
+    minimist "^1.2.5"
 
 ms@2.0.0:
   version "2.0.0"
@@ -1323,7 +1323,7 @@ rc@^1.0.1, rc@^1.1.6, rc@^1.2.7:
 
 readable-stream@^2.0.2, readable-stream@^2.0.6:
   version "2.3.6"
-  resolved "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz#b11c27d88b8ff1fbe070643cf94b0c79ae1b0aaf"
+  resolved "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz#b11c27d88b8ff1fbe070643cf94b0c79ae1b0aaf"
   dependencies:
     core-util-is "~1.0.0"
     inherits "~2.0.3"
@@ -1392,7 +1392,11 @@ safe-buffer@5.1.1:
   version "5.1.1"
   resolved "https://registry.yarnpkg.com/safe-buffer/-/safe-buffer-5.1.1.tgz#893312af69b2123def71f57889001671eeb2c853"
 
-safe-buffer@^5.0.1, safe-buffer@^5.1.2, safe-buffer@~5.1.0, safe-buffer@~5.1.1:
+safe-buffer@^5.0.1, safe-buffer@^5.1.2, safe-buffer@^5.2.1:
+  version "5.2.1"
+  resolved "https://registry.yarnpkg.com/safe-buffer/-/safe-buffer-5.2.1.tgz#1eaf9fa9bdb1fdd4ec75f58f9cdb4e6b7827eec6"
+
+safe-buffer@~5.1.0, safe-buffer@~5.1.1:
   version "5.1.2"
   resolved "https://registry.yarnpkg.com/safe-buffer/-/safe-buffer-5.1.2.tgz#991ec69d296e0313747d59bdfd2b745c35f8828d"
 
@@ -1622,16 +1626,16 @@ supports-color@^5.2.0, supports-color@^5.3.0:
     has-flag "^3.0.0"
 
 tar@^4:
-  version "4.4.6"
-  resolved "https://registry.yarnpkg.com/tar/-/tar-4.4.6.tgz#63110f09c00b4e60ac8bcfe1bf3c8660235fbc9b"
-  dependencies:
-    chownr "^1.0.1"
-    fs-minipass "^1.2.5"
-    minipass "^2.3.3"
-    minizlib "^1.1.0"
-    mkdirp "^0.5.0"
-    safe-buffer "^5.1.2"
-    yallist "^3.0.2"
+  version "4.4.19"
+  resolved "https://registry.yarnpkg.com/tar/-/tar-4.4.19.tgz#2e4d7263df26f2b914dee10c825ab132123742f3"
+  dependencies:
+    chownr "^1.1.4"
+    fs-minipass "^1.2.7"
+    minipass "^2.9.0"
+    minizlib "^1.3.3"
+    mkdirp "^0.5.5"
+    safe-buffer "^5.2.1"
+    yallist "^3.1.1"
 
 term-size@^1.2.0:
   version "1.2.0"
@@ -1805,6 +1809,6 @@ yallist@^2.1.2:
   version "2.1.2"
   resolved "https://registry.yarnpkg.com/yallist/-/yallist-2.1.2.tgz#1c11f9218f076089a47dd512f93c6699a6a81d52"
 
-yallist@^3.0.0, yallist@^3.0.2:
-  version "3.0.2"
-  resolved "https://registry.yarnpkg.com/yallist/-/yallist-3.0.2.tgz#8452b4bb7e83c7c188d8041c1a837c773d6d8bb9"
+yallist@^3.0.0, yallist@^3.1.1:
+  version "3.1.1"
+  resolved "https://registry.yarnpkg.com/yallist/-/yallist-3.1.1.tgz#dbb7daf9bfd8bac9ab45ebf602b8cbad0d5d08fd"