diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7bd6c47a5..c93b81ca4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,7 +8,9 @@
 
 ##### Bug Fixes
 
-* None.  
+* Cover more cases of the Dir.chdir breakages.  
+  [Danielle Tomlinson](https://github.com/dantoml)
+  [#421](https://github.com/CocoaPods/Xcodeproj/pull/421)
 
 
 ## 1.3.1 (2016-09-10)
diff --git a/lib/xcodeproj/plist/ffi.rb b/lib/xcodeproj/plist/ffi.rb
index 881bc854b..0b67557be 100644
--- a/lib/xcodeproj/plist/ffi.rb
+++ b/lib/xcodeproj/plist/ffi.rb
@@ -1,35 +1,6 @@
+
 module Xcodeproj
   module Plist
-    module Extensions
-      # Since Xcode 8 beta 4, calling `PBXProject.projectWithFile` breaks subsequent calls to
-      # `chdir`. While sounding ridiculous, this is unfortunately true and debugging it from the
-      # userland side showed no difference at all to successful calls to `chdir`, but the working
-      # directory is simply not changed in the end. This workaround is even more absurd, monkey
-      # patching all calls to `chdir` to use `__pthread_chdir` which appears to work.
-      module Dir
-        def self.chdir(path)
-          old_dir = Dir.getwd
-          res = actually_chdir(path)
-
-          if block_given?
-            begin
-              return yield
-            ensure
-              actually_chdir(old_dir)
-            end
-          end
-
-          res
-        end
-
-        def self.actually_chdir(path)
-          libc = Fiddle.dlopen '/usr/lib/libc.dylib'
-          f = Fiddle::Function.new(libc['__pthread_chdir'], [Fiddle::TYPE_VOIDP], Fiddle::TYPE_INT)
-          f.call(path.to_s)
-        end
-      end
-    end
-
     # Provides support for loading and serializing property list files via
     # Fiddle and CoreFoundation / Xcode.
     #
@@ -171,7 +142,10 @@ def ruby_hash_write_devtoolscore(hash, path)
         end
 
         def monkey_patch_chdir
-          Dir.send(:include, Extensions::Dir)
+          require 'xcodeproj/plist/ffi/chdir_override'
+          class << Dir
+            alias_method :chdir, :cp_chdir
+          end
         end
       end
     end
diff --git a/lib/xcodeproj/plist/ffi/chdir_override.rb b/lib/xcodeproj/plist/ffi/chdir_override.rb
new file mode 100644
index 000000000..86f66aa84
--- /dev/null
+++ b/lib/xcodeproj/plist/ffi/chdir_override.rb
@@ -0,0 +1,27 @@
+# Since Xcode 8 beta 4, calling `PBXProject.projectWithFile` breaks subsequent calls to
+# `chdir`. While sounding ridiculous, this is unfortunately true and debugging it from the
+# userland side showed no difference at all to successful calls to `chdir`, but the working
+# directory is simply not changed in the end. This workaround is even more absurd, monkey
+# patching all calls to `chdir` to use `__pthread_chdir` which appears to work.
+class Dir
+  def self.cp_chdir(path)
+    old_dir = Dir.getwd
+    res = cp_actually_chdir(path)
+
+    if block_given?
+      begin
+        return yield
+      ensure
+        cp_actually_chdir(old_dir)
+      end
+    end
+
+    res
+  end
+
+  def self.cp_actually_chdir(path)
+    libc = Fiddle.dlopen '/usr/lib/libc.dylib'
+    f = Fiddle::Function.new(libc['__pthread_chdir'], [Fiddle::TYPE_VOIDP], Fiddle::TYPE_INT)
+    f.call(path.to_s)
+  end
+end
diff --git a/spec/project_spec.rb b/spec/project_spec.rb
index b84620f99..f840ec8d9 100644
--- a/spec/project_spec.rb
+++ b/spec/project_spec.rb
@@ -87,6 +87,15 @@ module ProjectSpecs
         @project = Xcodeproj::Project.open(@path)
       end
 
+      it 'does not break the chdir system call' do
+        require 'pathname'
+        Dir.mktmpdir do |dir|
+          Dir.chdir(dir) do
+            Pathname(dir).realpath.to_s.should == Dir.getwd
+          end
+        end
+      end
+
       it 'sets itself as the owner of the root object' do
         # The root object might be referenced by other objects like
         # the PBXContainerItemProxy