diff --git a/Example/ChatExample.xcodeproj/project.pbxproj b/Example/ChatExample.xcodeproj/project.pbxproj
index e21d666c..495f2d3d 100644
--- a/Example/ChatExample.xcodeproj/project.pbxproj
+++ b/Example/ChatExample.xcodeproj/project.pbxproj
@@ -595,7 +595,7 @@
 				ONLY_ACTIVE_ARCH = YES;
 				SDKROOT = iphoneos;
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
-				SWIFT_VERSION = 3.0;
+				SWIFT_VERSION = 4.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 			};
 			name = Debug;
@@ -642,7 +642,7 @@
 				IPHONEOS_DEPLOYMENT_TARGET = 9.0;
 				MTL_ENABLE_DEBUG_INFO = NO;
 				SDKROOT = iphoneos;
-				SWIFT_VERSION = 3.0;
+				SWIFT_VERSION = 4.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				VALIDATE_PRODUCT = YES;
 			};
@@ -659,7 +659,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = com.messagekit.ChatExample;
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_VERSION = 3.0;
+				SWIFT_VERSION = 4.0;
 			};
 			name = Debug;
 		};
@@ -675,7 +675,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = com.messagekit.ChatExample;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
-				SWIFT_VERSION = 3.0;
+				SWIFT_VERSION = 4.0;
 			};
 			name = Release;
 		};
@@ -688,7 +688,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = com.hexedbits.ChatExampleTests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_VERSION = 3.0;
+				SWIFT_VERSION = 4.0;
 				TEST_HOST = "$(BUILT_PRODUCTS_DIR)/ChatExample.app/ChatExample";
 			};
 			name = Debug;
@@ -703,7 +703,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = com.hexedbits.ChatExampleTests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
-				SWIFT_VERSION = 3.0;
+				SWIFT_VERSION = 4.0;
 				TEST_HOST = "$(BUILT_PRODUCTS_DIR)/ChatExample.app/ChatExample";
 			};
 			name = Release;
@@ -716,7 +716,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = com.hexedbits.ChatExampleUITests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_VERSION = 3.0;
+				SWIFT_VERSION = 4.0;
 				TEST_TARGET_NAME = ChatExample;
 			};
 			name = Debug;
@@ -730,7 +730,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = com.hexedbits.ChatExampleUITests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
-				SWIFT_VERSION = 3.0;
+				SWIFT_VERSION = 4.0;
 				TEST_TARGET_NAME = ChatExample;
 			};
 			name = Release;
diff --git a/Example/Sources/ConversationViewController.swift b/Example/Sources/ConversationViewController.swift
index 60325a6b..30692f0d 100644
--- a/Example/Sources/ConversationViewController.swift
+++ b/Example/Sources/ConversationViewController.swift
@@ -45,7 +45,7 @@ class ConversationViewController: MessagesViewController {
                                                             action: #selector(handleKeyboardButton))
     }
     
-    func handleKeyboardButton() {
+  @objc func handleKeyboardButton() {
         
         let actionSheetController = UIAlertController(title: "Change Keyboard Style", message: nil, preferredStyle: .actionSheet)
         let actions = [
@@ -198,14 +198,14 @@ extension ConversationViewController: MessagesDataSource {
 
     func cellTopLabelAttributedText(for message: MessageType, at indexPath: IndexPath) -> NSAttributedString? {
         let name = message.sender.displayName
-        return NSAttributedString(string: name, attributes: [NSFontAttributeName: UIFont.preferredFont(forTextStyle: .caption1)])
+      return NSAttributedString(string: name, attributes: [NSAttributedStringKey.font: UIFont.preferredFont(forTextStyle: .caption1)])
     }
 
     func cellBottomLabelAttributedText(for message: MessageType, at indexPath: IndexPath) -> NSAttributedString? {
         let formatter = DateFormatter()
         formatter.dateStyle = .medium
         let dateString = formatter.string(from: message.sentDate)
-        return NSAttributedString(string: dateString, attributes: [NSFontAttributeName: UIFont.preferredFont(forTextStyle: .caption2)])
+      return NSAttributedString(string: dateString, attributes: [NSAttributedStringKey.font: UIFont.preferredFont(forTextStyle: .caption2)])
     }
 
 }
diff --git a/Example/Sources/SampleData.swift b/Example/Sources/SampleData.swift
index 377eede0..85297a09 100644
--- a/Example/Sources/SampleData.swift
+++ b/Example/Sources/SampleData.swift
@@ -46,11 +46,11 @@ struct SampleData {
 		let msg9Text = NSString(string: msg9String)
 		let msg9AttributedText = NSMutableAttributedString(string: String(msg9Text))
 
-        msg9AttributedText.addAttribute(NSFontAttributeName, value: UIFont.preferredFont(forTextStyle: .body), range: NSRange(location: 0, length: msg9Text.length))
-        msg9AttributedText.addAttributes([NSFontAttributeName: UIFont.monospacedDigitSystemFont(ofSize: UIFont.systemFontSize, weight: UIFontWeightBold)], range: msg9Text.range(of: ".attributedText()"))
-		msg9AttributedText.addAttributes([NSFontAttributeName: UIFont.boldSystemFont(ofSize: UIFont.systemFontSize)], range: msg9Text.range(of: "bold"))
-		msg9AttributedText.addAttributes([NSFontAttributeName: UIFont.italicSystemFont(ofSize: UIFont.systemFontSize)], range: msg9Text.range(of: "italic"))
-		msg9AttributedText.addAttributes([NSForegroundColorAttributeName: UIColor.red], range: msg9Text.range(of: "colored"))
+      msg9AttributedText.addAttribute(NSAttributedStringKey.font, value: UIFont.preferredFont(forTextStyle: .body), range: NSRange(location: 0, length: msg9Text.length))
+      msg9AttributedText.addAttributes([NSAttributedStringKey.font: UIFont.monospacedDigitSystemFont(ofSize: UIFont.systemFontSize, weight: UIFont.Weight.bold)], range: msg9Text.range(of: ".attributedText()"))
+      msg9AttributedText.addAttributes([NSAttributedStringKey.font: UIFont.boldSystemFont(ofSize: UIFont.systemFontSize)], range: msg9Text.range(of: "bold"))
+      msg9AttributedText.addAttributes([NSAttributedStringKey.font: UIFont.italicSystemFont(ofSize: UIFont.systemFontSize)], range: msg9Text.range(of: "italic"))
+      msg9AttributedText.addAttributes([NSAttributedStringKey.foregroundColor: UIColor.red], range: msg9Text.range(of: "colored"))
 		
 		var msg9 = MockMessage(attributedText: msg9AttributedText, sender: Jobs, messageId: UUID().uuidString)
         var msg10 = MockMessage(text: "1-800-555-0000", sender: Dan, messageId: UUID().uuidString)
diff --git a/MessageKit.podspec b/MessageKit.podspec
index 02db7826..4ead0343 100644
--- a/MessageKit.podspec
+++ b/MessageKit.podspec
@@ -12,7 +12,7 @@ Pod::Spec.new do |s|
    s.source_files = 'Sources/*.swift'
 
    s.pod_target_xcconfig = {
-      "SWIFT_VERSION" => "3.0",
+      "SWIFT_VERSION" => "4.0",
    }
 
    s.ios.deployment_target = '9.0'