diff --git a/npm-shrinkwrap.clean.json b/npm-shrinkwrap.clean.json
index fb2e10f343..a2d8b49afc 100644
--- a/npm-shrinkwrap.clean.json
+++ b/npm-shrinkwrap.clean.json
@@ -4196,10 +4196,10 @@
       "version": "0.3.5"
     },
     "mock-fs": {
-      "version": "2.7.1",
+      "version": "3.6.0",
       "dependencies": {
-        "rewire": {
-          "version": "2.0.1"
+        "semver": {
+          "version": "5.1.0"
         }
       }
     },
diff --git a/npm-shrinkwrap.json b/npm-shrinkwrap.json
index 437fbf8038..2979e3d8e8 100644
--- a/npm-shrinkwrap.json
+++ b/npm-shrinkwrap.json
@@ -6676,14 +6676,14 @@
       "resolved": "https://registry.npmjs.org/mktemp/-/mktemp-0.3.5.tgz"
     },
     "mock-fs": {
-      "version": "2.7.1",
-      "from": "mock-fs@>=2.5.0 <3.0.0",
-      "resolved": "https://registry.npmjs.org/mock-fs/-/mock-fs-2.7.1.tgz",
+      "version": "3.6.0",
+      "from": "mock-fs@3.6.0",
+      "resolved": "https://registry.npmjs.org/mock-fs/-/mock-fs-3.6.0.tgz",
       "dependencies": {
-        "rewire": {
-          "version": "2.0.1",
-          "from": "rewire@>=2.0.0 <2.1.0",
-          "resolved": "https://registry.npmjs.org/rewire/-/rewire-2.0.1.tgz"
+        "semver": {
+          "version": "5.1.0",
+          "from": "semver@>=5.0.3 <6.0.0",
+          "resolved": "https://registry.npmjs.org/semver/-/semver-5.1.0.tgz"
         }
       }
     },
diff --git a/package.json b/package.json
index 50afd346d6..a438076a43 100644
--- a/package.json
+++ b/package.json
@@ -93,7 +93,7 @@
     "merge2": "^0.3.5",
     "minimatch": "^2.0.1",
     "minimist": "^1.2.0",
-    "mock-fs": "^2.5.0",
+    "mock-fs": "^3.6.0",
     "node-uuid": "1.4.x",
     "on-headers": "^1.0.0",
     "parse5": "1.3.2",
diff --git a/tools/broccoli/broccoli-flatten.spec.ts b/tools/broccoli/broccoli-flatten.spec.ts
index d89b613a75..b58fd585d5 100644
--- a/tools/broccoli/broccoli-flatten.spec.ts
+++ b/tools/broccoli/broccoli-flatten.spec.ts
@@ -1,11 +1,6 @@
 /// <reference path="../typings/node/node.d.ts" />
 /// <reference path="../typings/jasmine/jasmine.d.ts" />
 
-console.warn(
-    "Skipping all tests in broccoli-flatten.spec.ts because they require mock-fs which is currently incompatible with node 4.x. See: https://github.com/tschaub/mock-fs/issues/59");
-
-
-/*
 let mockfs = require('mock-fs');
 import fs = require('fs');
 import path = require('path');
@@ -79,4 +74,3 @@ describe('Flatten', () => {
                       path.sep + "file-1.txt'");
   });
 });
-*/
diff --git a/tools/broccoli/broccoli-merge-trees.spec.ts b/tools/broccoli/broccoli-merge-trees.spec.ts
index 0576b654ad..c1c659f546 100644
--- a/tools/broccoli/broccoli-merge-trees.spec.ts
+++ b/tools/broccoli/broccoli-merge-trees.spec.ts
@@ -1,11 +1,6 @@
 /// <reference path="../typings/node/node.d.ts" />
 /// <reference path="../typings/jasmine/jasmine.d.ts" />
 
-console.warn(
-    "Skipping all tests in broccoli-merge-trees.spec.ts because they require mock-fs which is currently incompatible with node 4.x. See: https://github.com/tschaub/mock-fs/issues/59");
-
-
-/*
 let mockfs = require('mock-fs');
 import fs = require('fs');
 import {TreeDiffer} from './tree-differ';
@@ -94,4 +89,3 @@ describe('MergeTrees', () => {
             'Either remove the duplicate or enable the "overwrite" option for this merge.');
   });
 });
-*/
diff --git a/tools/broccoli/tree-differ.spec.ts b/tools/broccoli/tree-differ.spec.ts
index 00b6762ae1..0a2205ca52 100644
--- a/tools/broccoli/tree-differ.spec.ts
+++ b/tools/broccoli/tree-differ.spec.ts
@@ -1,18 +1,13 @@
 /// <reference path="../typings/node/node.d.ts" />
 /// <reference path="../typings/jasmine/jasmine.d.ts" />
 
-console.warn(
-    "Skipping all tests in tree-differ.spec.ts because they require mock-fs which is currently incompatible with node 4.x. See: https://github.com/tschaub/mock-fs/issues/59");
-
-
-/*
 let mockfs = require('mock-fs');
 import fs = require('fs');
 import path = require('path');
 import {TreeDiffer} from './tree-differ';
 
 
-xdescribe('TreeDiffer', () => {
+describe('TreeDiffer', () => {
 
   afterEach(() => mockfs.restore());
 
@@ -381,4 +376,3 @@ xdescribe('TreeDiffer', () => {
     });
   });
 });
-*/