diff --git a/features/site_configuration.feature b/features/site_configuration.feature
index 4f807eae..6ca59601 100644
--- a/features/site_configuration.feature
+++ b/features/site_configuration.feature
@@ -233,3 +233,26 @@ Feature: Site configuration
     Then the _site directory should exist
     And I should see "Whatever" in "_site/index.html"
     And I should see "this is a test" in "_site/test.txt"
+
+  Scenario: Add an empty whitelist to restrict all gems
+    Given I have an "index.html" file that contains "Whatever"
+    And I have a configuration file with:
+      | key       | value |
+      | gems      | [jekyll_test_plugin] |
+      | whitelist | [] |
+    When I run jekyll in safe mode
+    Then the _site directory should exist
+    And I should see "Whatever" in "_site/index.html"
+    And the "_site/test.txt" file should not exist
+
+  Scenario: Add a whitelist to restrict some gems but allow others
+    Given I have an "index.html" file that contains "Whatever"
+    And I have a configuration file with:
+      | key       | value |
+      | gems      | [jekyll_test_plugin, jekyll_test_plugin_malicious] |
+      | whitelist | [jekyll_test_plugin] |
+    When I run jekyll in safe mode
+    Then the _site directory should exist
+    And I should see "Whatever" in "_site/index.html"
+    And the "_site/test.txt" file should exist
+    And I should see "this is a test" in "_site/test.txt"
diff --git a/features/step_definitions/jekyll_steps.rb b/features/step_definitions/jekyll_steps.rb
index 7a74486b..5f8f93fc 100644
--- a/features/step_definitions/jekyll_steps.rb
+++ b/features/step_definitions/jekyll_steps.rb
@@ -126,6 +126,10 @@ When /^I run jekyll$/ do
   run_jekyll
 end
 
+When /^I run jekyll in safe mode$/ do
+  run_jekyll(:safe => true)
+end
+
 When /^I run jekyll with drafts$/ do
   run_jekyll(:drafts => true)
 end
diff --git a/features/support/env.rb b/features/support/env.rb
index 5ccbab98..5fcacc8a 100644
--- a/features/support/env.rb
+++ b/features/support/env.rb
@@ -15,6 +15,7 @@ def run_jekyll(opts = {})
   command = JEKYLL_PATH.clone
   command << " build"
   command << " --drafts" if opts[:drafts]
+  command << " --safe" if opts[:safe]
   command << " >> /dev/null 2>&1" if opts[:debug].nil?
   system command
 end
@@ -50,7 +51,7 @@ def seconds_agnostic_datetime(datetime = Time.now)
   pieces = datetime.to_s.split(" ")
   if pieces.size == 6 # Ruby 1.8.7
     date = pieces[0..2].join(" ")
-    time = seconds_agnostic_time(pieces[3]) 
+    time = seconds_agnostic_time(pieces[3])
     zone = pieces[4..5].join(" ")
   else # Ruby 1.9.1 or greater
     date, time, zone = pieces