diff --git a/Source/ShoutFactory.swift b/Source/ShoutFactory.swift
index 3211985..37b99c6 100644
--- a/Source/ShoutFactory.swift
+++ b/Source/ShoutFactory.swift
@@ -208,7 +208,7 @@ open class ShoutView: UIView {
 
   // MARK: - Timer methods
 
-  open func displayTimerDidFire() {
+    @objc open func displayTimerDidFire() {
     shouldSilent = true
 
     if panGestureActive { return }
@@ -262,7 +262,7 @@ open class ShoutView: UIView {
 
   // MARK: - Handling screen orientation
 
-  func orientationDidChange() {
+    @objc func orientationDidChange() {
     setupFrames()
   }
 }
diff --git a/Source/WhisperFactory.swift b/Source/WhisperFactory.swift
index 7043558..380fe43 100644
--- a/Source/WhisperFactory.swift
+++ b/Source/WhisperFactory.swift
@@ -173,11 +173,11 @@ class WhisperFactory: NSObject {
 
   // MARK: - Timer methods
 
-  func delayFired(_ timer: Timer) {
+    @objc func delayFired(_ timer: Timer) {
     hideView()
   }
 
-  func presentFired(_ timer: Timer) {
+    @objc func presentFired(_ timer: Timer) {
     guard let navigationController = self.navigationController,
       let userInfo = timer.userInfo as? [String : AnyObject],
       let title = userInfo["title"] as? String,
@@ -252,7 +252,7 @@ class WhisperFactory: NSObject {
 
   // MARK: - Handling screen orientation
 
-  func orientationDidChange() {
+    @objc func orientationDidChange() {
     guard let navigationController = self.navigationController else { return }
     for subview in navigationController.navigationBar.subviews {
       guard let whisper = subview as? WhisperView else { continue }
diff --git a/Source/WhistleFactory.swift b/Source/WhistleFactory.swift
index e25105f..019450c 100644
--- a/Source/WhistleFactory.swift
+++ b/Source/WhistleFactory.swift
@@ -103,7 +103,7 @@ open class WhistleFactory: UIViewController {
         NSString(string: text).boundingRect(
           with: CGSize(width: labelWidth, height: CGFloat.infinity),
           options: NSStringDrawingOptions.usesLineFragmentOrigin,
-          attributes: [NSFontAttributeName: titleLabel.font],
+          attributes: [NSAttributedStringKey.font: titleLabel.font],
           context: nil
         )
       titleLabelHeight = CGFloat(neededDimensions.size.height)
@@ -166,11 +166,11 @@ open class WhistleFactory: UIViewController {
 
   // MARK: - Timer methods
 
-  public func timerDidFire() {
+    @objc public func timerDidFire() {
     hide()
   }
 
-  func orientationDidChange() {
+    @objc func orientationDidChange() {
     if whistleWindow.isKeyWindow {
       setupFrames()
       hide()
diff --git a/Whisper.podspec b/Whisper.podspec
index b271304..6cd0a04 100644
--- a/Whisper.podspec
+++ b/Whisper.podspec
@@ -11,5 +11,5 @@ Pod::Spec.new do |s|
   s.requires_arc = true
   s.source_files = 'Source/**/*'
   s.frameworks = 'UIKit', 'Foundation'
-  s.pod_target_xcconfig = { 'SWIFT_VERSION' => '3.0' }
+  s.pod_target_xcconfig = { 'SWIFT_VERSION' => '4.0' }
 end
diff --git a/Whisper.xcodeproj/project.pbxproj b/Whisper.xcodeproj/project.pbxproj
index 17c612c..ed17efb 100644
--- a/Whisper.xcodeproj/project.pbxproj
+++ b/Whisper.xcodeproj/project.pbxproj
@@ -133,7 +133,7 @@
 			isa = PBXProject;
 			attributes = {
 				LastSwiftUpdateCheck = 0720;
-				LastUpgradeCheck = 0800;
+				LastUpgradeCheck = 0900;
 				ORGANIZATIONNAME = "Hyper Interaktiv AS";
 				TargetAttributes = {
 					290530F81C20511C00FB382C = {
@@ -198,14 +198,20 @@
 				CLANG_CXX_LIBRARY = "libc++";
 				CLANG_ENABLE_MODULES = YES;
 				CLANG_ENABLE_OBJC_ARC = YES;
+				CLANG_WARN_BLOCK_CAPTURE_AUTORELEASING = YES;
 				CLANG_WARN_BOOL_CONVERSION = YES;
+				CLANG_WARN_COMMA = YES;
 				CLANG_WARN_CONSTANT_CONVERSION = YES;
 				CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES_ERROR;
 				CLANG_WARN_EMPTY_BODY = YES;
 				CLANG_WARN_ENUM_CONVERSION = YES;
 				CLANG_WARN_INFINITE_RECURSION = YES;
 				CLANG_WARN_INT_CONVERSION = YES;
+				CLANG_WARN_NON_LITERAL_NULL_CONVERSION = YES;
+				CLANG_WARN_OBJC_LITERAL_CONVERSION = YES;
 				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
+				CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
+				CLANG_WARN_STRICT_PROTOTYPES = YES;
 				CLANG_WARN_SUSPICIOUS_MOVE = YES;
 				CLANG_WARN_UNREACHABLE_CODE = YES;
 				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
@@ -248,14 +254,20 @@
 				CLANG_CXX_LIBRARY = "libc++";
 				CLANG_ENABLE_MODULES = YES;
 				CLANG_ENABLE_OBJC_ARC = YES;
+				CLANG_WARN_BLOCK_CAPTURE_AUTORELEASING = YES;
 				CLANG_WARN_BOOL_CONVERSION = YES;
+				CLANG_WARN_COMMA = YES;
 				CLANG_WARN_CONSTANT_CONVERSION = YES;
 				CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES_ERROR;
 				CLANG_WARN_EMPTY_BODY = YES;
 				CLANG_WARN_ENUM_CONVERSION = YES;
 				CLANG_WARN_INFINITE_RECURSION = YES;
 				CLANG_WARN_INT_CONVERSION = YES;
+				CLANG_WARN_NON_LITERAL_NULL_CONVERSION = YES;
+				CLANG_WARN_OBJC_LITERAL_CONVERSION = YES;
 				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
+				CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
+				CLANG_WARN_STRICT_PROTOTYPES = YES;
 				CLANG_WARN_SUSPICIOUS_MOVE = YES;
 				CLANG_WARN_UNREACHABLE_CODE = YES;
 				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
@@ -299,7 +311,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = no.hyper.Whisper;
 				PRODUCT_NAME = Whisper;
 				SKIP_INSTALL = YES;
-				SWIFT_VERSION = 3.0;
+				SWIFT_VERSION = 4.0;
 			};
 			name = Debug;
 		};
@@ -318,7 +330,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = no.hyper.Whisper;
 				PRODUCT_NAME = Whisper;
 				SKIP_INSTALL = YES;
-				SWIFT_VERSION = 3.0;
+				SWIFT_VERSION = 4.0;
 			};
 			name = Release;
 		};
diff --git a/Whisper.xcodeproj/xcshareddata/xcschemes/Whisper-iOS.xcscheme b/Whisper.xcodeproj/xcshareddata/xcschemes/Whisper-iOS.xcscheme
index dbe103b..920f78d 100644
--- a/Whisper.xcodeproj/xcshareddata/xcschemes/Whisper-iOS.xcscheme
+++ b/Whisper.xcodeproj/xcshareddata/xcschemes/Whisper-iOS.xcscheme
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "0800"
+   LastUpgradeVersion = "0900"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
@@ -26,6 +26,7 @@
       buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
       shouldUseLaunchSchemeArgsEnv = "YES">
       <Testables>
       </Testables>
@@ -36,6 +37,7 @@
       buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
       launchStyle = "0"
       useCustomWorkingDirectory = "NO"
       ignoresPersistentStateOnLaunch = "NO"