diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9540e9b8..afe48699 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 ## master
 
+* Show an alert if CP is going to re-integrate your project  
+  [orta](https://github.com/orta)  
+  [#299](https://github.com/CocoaPods/CocoaPods-app/pull/299)
+
 * Polish for Source Menus & Pod Autocomplete improvements  
   [orta](https://github.com/orta)  
   [#298](https://github.com/CocoaPods/CocoaPods-app/pull/298)
diff --git a/app/CPReflectionService/RBObject+CocoaPods.rb b/app/CPReflectionService/RBObject+CocoaPods.rb
index 82c9f929..d34677e0 100644
--- a/app/CPReflectionService/RBObject+CocoaPods.rb
+++ b/app/CPReflectionService/RBObject+CocoaPods.rb
@@ -58,7 +58,14 @@ def self.analyze_podfile(podfile, installation_root)
       end
 
       uses_frameworks = config.podfile.target_definitions.first.last.to_hash["uses_frameworks"]
-      { "projects" => user_projects, "pod_targets" => pod_targets, "uses_frameworks" => uses_frameworks}
+      last_installed_version = config.sandbox.manifest.cocoapods_version.to_s
+
+      {
+        "projects" => user_projects,
+        "pod_targets" => pod_targets,
+        "uses_frameworks" => uses_frameworks,
+        "cocoapods_build_version" => last_installed_version
+      }
     end
 
     def self.sources_manager
diff --git a/app/CocoaPods/CPDocumentController.swift b/app/CocoaPods/CPDocumentController.swift
index 95674262..95567c21 100644
--- a/app/CocoaPods/CPDocumentController.swift
+++ b/app/CocoaPods/CPDocumentController.swift
@@ -73,9 +73,9 @@ class CPDocumentController: NSDocumentController {
       }
       else {
         let projectName = xcodeprojURL.lastPathComponent!
-        let localized = NSLocalizedString("POD_DEINTEGRATE_CONFIRMATION", comment: "")
+        let localized = ~"POD_DEINTEGRATE_CONFIRMATION"
         let alert = NSAlert()
-        alert.messageText = NSLocalizedString("POD_DEINTEGRATE_INFO", comment: "")
+        alert.messageText = ~"POD_DEINTEGRATE_INFO"
         alert.informativeText = String.localizedStringWithFormat(localized, projectName)
         alert.runModal()
       }
diff --git a/app/CocoaPods/CPPodfileEditorViewController.swift b/app/CocoaPods/CPPodfileEditorViewController.swift
index c8c7a453..1ea90ad3 100644
--- a/app/CocoaPods/CPPodfileEditorViewController.swift
+++ b/app/CocoaPods/CPPodfileEditorViewController.swift
@@ -342,7 +342,18 @@ extension EditorLineSelection {
 extension CPPodfileEditorViewController: CPUserProjectDelegate {
   
   func contentDidChangeinUserProject(userProject: CPUserProject) {
-    editor.string = userProject.contents
+    let contentChanged = editor.string != userProject.contents
+    let appIsActive = NSApplication.sharedApplication().active
+
+    if contentChanged && !appIsActive {
+      let selection = editor.textView.selectedRange()
+      let scroll = editor.scrollView.visibleRect
+
+      editor.string = userProject.contents
+
+      editor.textView.selectedRange = selection
+      editor.scrollView.scrollPoint(scroll.origin)
+    }
     
     // Passing the message on to the syntax checker
     syntaxChecker.textDidChange(NSNotification(name: "", object: nil))
diff --git a/app/CocoaPods/CPPodfilePluginCoordinator.swift b/app/CocoaPods/CPPodfilePluginCoordinator.swift
index ffa5e202..2f646489 100644
--- a/app/CocoaPods/CPPodfilePluginCoordinator.swift
+++ b/app/CocoaPods/CPPodfilePluginCoordinator.swift
@@ -49,7 +49,7 @@ class CPPodfilePluginCoordinator: NSObject {
 
       dispatch_async(dispatch_get_main_queue()) {
         let inflectedPlugin = (self.pluginsToInstall.count == 1) ? "plugin" : "plugins"
-        self.controller.showWarningLabelWithSender("You need to install \(self.pluginsToInstall.count) \(inflectedPlugin) for this Podfile", actionTitle: "Install", target: self, action: "showInstaller", animated:true)
+        self.controller.showWarningLabelWithSender("You need to install \(self.pluginsToInstall.count) \(inflectedPlugin) for this Podfile", actionTitle: "Install", target: self, action: #selector(CPPodfilePluginCoordinator.showInstaller), animated:true)
       }
     }
   }
diff --git a/app/CocoaPods/CPPodfileViewController.swift b/app/CocoaPods/CPPodfileViewController.swift
index 32729959..e4dcdbf3 100644
--- a/app/CocoaPods/CPPodfileViewController.swift
+++ b/app/CocoaPods/CPPodfileViewController.swift
@@ -56,12 +56,31 @@ class CPPodfileViewController: NSViewController, NSTabViewDelegate {
     // we should show "Podfile for ProjectName" instead
     userProject.registerForFullMetadataCallback {
       guard let targets = self.userProject.xcodeIntegrationDictionary["projects"] as? [String:AnyObject] else { return }
-      if targets.keys.count == 1 {
-        let project = targets.keys.first!
-        let url = NSURL(fileURLWithPath: project)
-        let name = url.lastPathComponent!.stringByReplacingOccurrencesOfString(".xcproj", withString: "")
-        self.actionTitleLabel.stringValue = "Podfile for \(name)"
-      }
+      self.updatePodfileNameIfPossible(targets)
+    }
+  }
+
+  /// As CP will deintegrate, and re-integrate that app, we should show a warning
+  /// that is is going to happen
+  /// buildVersion will be cast to a string
+  func shouldShowInstallWarningForMajorChange(buildVersion: AnyObject?) -> Bool {
+    guard
+      let version = buildVersion as? String,
+      let majorLastInstallVersion = version.componentsSeparatedByString(".").first,
+      appVersion =  NSBundle.mainBundle().objectForInfoDictionaryKey("CFBundleShortVersionString") as? String,
+      majorAppVersion = appVersion.componentsSeparatedByString(".").first
+
+    else { return false}
+
+    return Int(majorAppVersion) > Int(majorLastInstallVersion)
+  }
+
+  func updatePodfileNameIfPossible(targets: [String: AnyObject]) {
+    if targets.keys.count == 1 {
+      let project = targets.keys.first!
+      let url = NSURL(fileURLWithPath: project)
+      let name = url.lastPathComponent!.stringByReplacingOccurrencesOfString(".xcproj", withString: "")
+      actionTitleLabel.stringValue = "Podfile for \(name)"
     }
   }
 
@@ -70,33 +89,50 @@ class CPPodfileViewController: NSViewController, NSTabViewDelegate {
   }
 
   @IBAction func install(obj: AnyObject) {
-    userProject.saveDocument(self)
     let options = InstallOptions(verbose: false)
-    installAction.performAction(.Install(options: options))
-    showConsoleTab(self)
+    performInstallAction(.Install(options: options))
   }
 
   @IBAction func installVerbose(obj: AnyObject) {
-    userProject.saveDocument(self)
     let options = InstallOptions(verbose: true)
-    installAction.performAction(.Install(options: options))
-    showConsoleTab(self)
+    performInstallAction(.Install(options: options))
   }
 
   @IBAction func installUpdate(obj: AnyObject) {
-    userProject.saveDocument(self)
     let options = InstallOptions(verbose: false)
-    installAction.performAction(.Update(options: options))
-    showConsoleTab(self)
+    performInstallAction(.Update(options: options))
   }
 
   @IBAction func installUpdateVerbose(obj: AnyObject) {
-    userProject.saveDocument(self)
     let options = InstallOptions(verbose: true)
-    installAction.performAction(.Update(options: options))
+    performInstallAction(.Update(options: options))
+  }
+
+  func performInstallAction(action: InstallActionType) {
+    userProject.saveDocument(self)
+
+    let lastInstalledVersion = userProject.xcodeIntegrationDictionary["cocoapods_build_version"]
+    if shouldShowInstallWarningForMajorChange(lastInstalledVersion) {
+      if promptForInstallMigration(lastInstalledVersion) == false { return }
+    }
+
+    installAction.performAction(action)
     showConsoleTab(self)
   }
 
+  func promptForInstallMigration(buildVersion: AnyObject?) -> Bool {
+    guard let
+      appVersion =  NSBundle.mainBundle().objectForInfoDictionaryKey("CFBundleShortVersionString") as? String,
+      version = buildVersion as? String else { return true }
+
+    let alert = NSAlert()
+    alert.messageText = ~"REINTEGRATION_ALERT_FORMAT_TITLE"
+    alert.informativeText = String(format: ~"REINTEGRATION_ALERT_FORMAT_MESSAGE", version, appVersion)
+    alert.addButtonWithTitle(~"REINTEGRATION_ALERT_CONFIRM")
+    alert.addButtonWithTitle(~"REINTEGRATION_ALERT_CANCEL")
+    return alert.runModal() == NSAlertFirstButtonReturn
+  }
+
   @IBOutlet var installMenu: NSMenu!
   @IBAction func showInstallOptions(button: NSButton) {
     guard let event = NSApp.currentEvent else { return }
diff --git a/app/CocoaPods/CPSpotlightDocumentSource.swift b/app/CocoaPods/CPSpotlightDocumentSource.swift
index d607d23c..29ff161d 100644
--- a/app/CocoaPods/CPSpotlightDocumentSource.swift
+++ b/app/CocoaPods/CPSpotlightDocumentSource.swift
@@ -47,7 +47,7 @@ class CPSpotlightDocumentSource: CPDocumentSource {
 
   func queryGatheringFinished(notification: NSNotification) {
     // let NSMetadataQuery finish when there are files available, if not finish the query
-    self.performSelector(Selector("queryFinished"), withObject: nil, afterDelay: 2.0)
+    self.performSelector(#selector(CPSpotlightDocumentSource.queryFinished), withObject: nil, afterDelay: 2.0)
   }
   
   func queryFinished() {
diff --git a/app/CocoaPods/CPUserProject.m b/app/CocoaPods/CPUserProject.m
index 243a1756..ea1845ce 100644
--- a/app/CocoaPods/CPUserProject.m
+++ b/app/CocoaPods/CPUserProject.m
@@ -89,7 +89,6 @@ - (void)presentedItemDidChange
       });
     }
   }
-  
 }
 
 @end
diff --git a/app/CocoaPods/Supporting Files/Localizable.strings b/app/CocoaPods/Supporting Files/Localizable.strings
index 60ec836d..dbb9ff85 100644
--- a/app/CocoaPods/Supporting Files/Localizable.strings	
+++ b/app/CocoaPods/Supporting Files/Localizable.strings	
@@ -43,4 +43,9 @@
 "REPO_UPDATE_FAILED_NOTIFICATION_TITLE" = "Repo not Updated";
 
 "PLUGIN_FAILED_TO_INSTALL_MESSAGE" = "Failed to Install Plugins";
-"PLUGINS_ALL_INSTALLED_MESSAGE" = "Installed Plugins";
\ No newline at end of file
+"PLUGINS_ALL_INSTALLED_MESSAGE" = "Installed Plugins";
+
+"REINTEGRATION_ALERT_FORMAT_TITLE" = "Re-integration";
+"REINTEGRATION_ALERT_FORMAT_MESSAGE" = "CocoaPods is going to migrate your project from %@ to %@, this is considered a breaking change. To migrate, CocoaPods will re-install your integration from scratch, including re-downloading all Pods";
+"REINTEGRATION_ALERT_CONFIRM" = "Okay, lets do it";
+"REINTEGRATION_ALERT_CANCEL" = "Cancel";
\ No newline at end of file