diff --git a/DataSource.xcodeproj/project.pbxproj b/DataSource.xcodeproj/project.pbxproj
index ab8d1c2..a5af096 100644
--- a/DataSource.xcodeproj/project.pbxproj
+++ b/DataSource.xcodeproj/project.pbxproj
@@ -375,13 +375,13 @@
 			isa = PBXProject;
 			attributes = {
 				LastSwiftUpdateCheck = 0820;
-				LastUpgradeCheck = 0810;
+				LastUpgradeCheck = 0900;
 				ORGANIZATIONNAME = "aaa - all about apps GmbH";
 				TargetAttributes = {
 					395D147B1B90610A00658680 = {
 						CreatedOnToolsVersion = 7.0;
 						DevelopmentTeam = PRXJBCN9SJ;
-						LastSwiftMigration = 0800;
+						LastSwiftMigration = 0900;
 						ProvisioningStyle = Automatic;
 						SystemCapabilities = {
 							com.apple.GameCenter = {
@@ -394,11 +394,12 @@
 					};
 					395D14A31B90612D00658680 = {
 						CreatedOnToolsVersion = 7.0;
-						LastSwiftMigration = 0820;
+						LastSwiftMigration = 0900;
 					};
 					39A848631E5E1D9600D7DBC2 = {
 						CreatedOnToolsVersion = 8.2.1;
 						DevelopmentTeam = PRXJBCN9SJ;
+						LastSwiftMigration = 0900;
 						ProvisioningStyle = Automatic;
 						TestTargetID = 395D147B1B90610A00658680;
 					};
@@ -565,14 +566,20 @@
 				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;
@@ -611,14 +618,20 @@
 				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;
@@ -659,7 +672,8 @@
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				PROVISIONING_PROFILE = "";
 				PROVISIONING_PROFILE_SPECIFIER = "";
-				SWIFT_VERSION = 3.0;
+				SWIFT_SWIFT3_OBJC_INFERENCE = On;
+				SWIFT_VERSION = 4.0;
 			};
 			name = Debug;
 		};
@@ -681,7 +695,8 @@
 				PROVISIONING_PROFILE = "";
 				PROVISIONING_PROFILE_SPECIFIER = "";
 				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
-				SWIFT_VERSION = 3.0;
+				SWIFT_SWIFT3_OBJC_INFERENCE = On;
+				SWIFT_VERSION = 4.0;
 			};
 			name = Release;
 		};
@@ -706,7 +721,8 @@
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SKIP_INSTALL = YES;
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
-				SWIFT_VERSION = 3.0;
+				SWIFT_SWIFT3_OBJC_INFERENCE = On;
+				SWIFT_VERSION = 4.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				VERSIONING_SYSTEM = "apple-generic";
 				VERSION_INFO_PREFIX = "";
@@ -734,7 +750,8 @@
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SKIP_INSTALL = YES;
 				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
-				SWIFT_VERSION = 3.0;
+				SWIFT_SWIFT3_OBJC_INFERENCE = On;
+				SWIFT_VERSION = 4.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				VERSIONING_SYSTEM = "apple-generic";
 				VERSION_INFO_PREFIX = "";
@@ -758,7 +775,8 @@
 				PRODUCT_BUNDLE_IDENTIFIER = com.buchetics.DataSourceTests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_ACTIVE_COMPILATION_CONDITIONS = DEBUG;
-				SWIFT_VERSION = 3.0;
+				SWIFT_SWIFT3_OBJC_INFERENCE = On;
+				SWIFT_VERSION = 4.0;
 				TEST_HOST = "$(BUILT_PRODUCTS_DIR)/Example.app/Example";
 			};
 			name = Debug;
@@ -780,7 +798,8 @@
 				PRODUCT_BUNDLE_IDENTIFIER = com.buchetics.DataSourceTests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
-				SWIFT_VERSION = 3.0;
+				SWIFT_SWIFT3_OBJC_INFERENCE = On;
+				SWIFT_VERSION = 4.0;
 				TEST_HOST = "$(BUILT_PRODUCTS_DIR)/Example.app/Example";
 			};
 			name = Release;
diff --git a/DataSource.xcodeproj/project.xcworkspace/xcshareddata/WorkspaceSettings.xcsettings b/DataSource.xcodeproj/project.xcworkspace/xcshareddata/WorkspaceSettings.xcsettings
new file mode 100644
index 0000000..3ddf867
--- /dev/null
+++ b/DataSource.xcodeproj/project.xcworkspace/xcshareddata/WorkspaceSettings.xcsettings
@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>BuildSystemType</key>
+	<string>Latest</string>
+</dict>
+</plist>
diff --git a/DataSource.xcodeproj/xcshareddata/xcschemes/DataSource.xcscheme b/DataSource.xcodeproj/xcshareddata/xcschemes/DataSource.xcscheme
index 21b1c7c..a0addad 100644
--- a/DataSource.xcodeproj/xcshareddata/xcschemes/DataSource.xcscheme
+++ b/DataSource.xcodeproj/xcshareddata/xcschemes/DataSource.xcscheme
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "0810"
+   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"
       codeCoverageEnabled = "YES">
       <Testables>
@@ -33,7 +34,7 @@
             skipped = "NO">
             <BuildableReference
                BuildableIdentifier = "primary"
-               BlueprintIdentifier = "395D14AC1B90612D00658680"
+               BlueprintIdentifier = "39A848631E5E1D9600D7DBC2"
                BuildableName = "DataSourceTests.xctest"
                BlueprintName = "DataSourceTests"
                ReferencedContainer = "container:DataSource.xcodeproj">
@@ -56,6 +57,7 @@
       buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
       launchStyle = "0"
       useCustomWorkingDirectory = "NO"
       ignoresPersistentStateOnLaunch = "NO"
diff --git a/DataSource.xcodeproj/xcshareddata/xcschemes/DataSourceTests.xcscheme b/DataSource.xcodeproj/xcshareddata/xcschemes/DataSourceTests.xcscheme
index e5ee577..124724d 100644
--- a/DataSource.xcodeproj/xcshareddata/xcschemes/DataSourceTests.xcscheme
+++ b/DataSource.xcodeproj/xcshareddata/xcschemes/DataSourceTests.xcscheme
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "0810"
+   LastUpgradeVersion = "0900"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
@@ -26,13 +26,14 @@
       buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
       shouldUseLaunchSchemeArgsEnv = "YES">
       <Testables>
          <TestableReference
             skipped = "NO">
             <BuildableReference
                BuildableIdentifier = "primary"
-               BlueprintIdentifier = "395D14AC1B90612D00658680"
+               BlueprintIdentifier = "39A848631E5E1D9600D7DBC2"
                BuildableName = "DataSourceTests.xctest"
                BlueprintName = "DataSourceTests"
                ReferencedContainer = "container:DataSource.xcodeproj">
@@ -55,6 +56,7 @@
       buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
       launchStyle = "0"
       useCustomWorkingDirectory = "NO"
       ignoresPersistentStateOnLaunch = "NO"
diff --git a/DataSource.xcodeproj/xcshareddata/xcschemes/Example.xcscheme b/DataSource.xcodeproj/xcshareddata/xcschemes/Example.xcscheme
index 44b32a4..a2c2efd 100644
--- a/DataSource.xcodeproj/xcshareddata/xcschemes/Example.xcscheme
+++ b/DataSource.xcodeproj/xcshareddata/xcschemes/Example.xcscheme
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "0810"
+   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>
          <TestableReference
@@ -42,7 +43,7 @@
             skipped = "NO">
             <BuildableReference
                BuildableIdentifier = "primary"
-               BlueprintIdentifier = "395D14AC1B90612D00658680"
+               BlueprintIdentifier = "39A848631E5E1D9600D7DBC2"
                BuildableName = "DataSourceTests.xctest"
                BlueprintName = "DataSourceTests"
                ReferencedContainer = "container:DataSource.xcodeproj">
@@ -65,6 +66,7 @@
       buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
       launchStyle = "0"
       useCustomWorkingDirectory = "NO"
       ignoresPersistentStateOnLaunch = "NO"
diff --git a/DataSource/Info.plist b/DataSource/Info.plist
index 755d287..01efda1 100644
--- a/DataSource/Info.plist
+++ b/DataSource/Info.plist
@@ -15,11 +15,11 @@
 	<key>CFBundlePackageType</key>
 	<string>FMWK</string>
 	<key>CFBundleShortVersionString</key>
-	<string>4.0.3</string>
+	<string>5.0</string>
 	<key>CFBundleSignature</key>
 	<string>????</string>
 	<key>CFBundleVersion</key>
-	<string>43</string>
+	<string>50</string>
 	<key>NSPrincipalClass</key>
 	<string></string>
 </dict>
diff --git a/Example/Info.plist b/Example/Info.plist
index c36c6d3..2c37027 100644
--- a/Example/Info.plist
+++ b/Example/Info.plist
@@ -15,11 +15,11 @@
 	<key>CFBundlePackageType</key>
 	<string>APPL</string>
 	<key>CFBundleShortVersionString</key>
-	<string>4.0.3</string>
+	<string>5.0</string>
 	<key>CFBundleSignature</key>
 	<string>????</string>
 	<key>CFBundleVersion</key>
-	<string>43</string>
+	<string>50</string>
 	<key>LSRequiresIPhoneOS</key>
 	<true/>
 	<key>UILaunchStoryboardName</key>
diff --git a/Example/ViewControllers/Examples/RandomPersonsViewController.swift b/Example/ViewControllers/Examples/RandomPersonsViewController.swift
index 7add73f..efc2288 100644
--- a/Example/ViewControllers/Examples/RandomPersonsViewController.swift
+++ b/Example/ViewControllers/Examples/RandomPersonsViewController.swift
@@ -74,7 +74,7 @@ class RandomPersonsViewController: UITableViewController {
 extension RandomPersonsViewController {
     
     override func scrollViewDidScroll(_ scrollView: UIScrollView) {
-        print("Scrolled: \(scrollView.contentOffset.y)")
+        print("scrolled: \(scrollView.contentOffset.y)")
     }
     
 }
@@ -87,7 +87,7 @@ struct Person {
     let lastName: String
     
     func lastNameStartsWith(letters: Set<String>) -> Bool {
-        let letter = lastName.substring(to: lastName.index(lastName.startIndex, offsetBy: 1))
+        let letter = String(lastName[lastName.startIndex])
         return letters.contains(letter)
     }
     
diff --git a/MBDataSource.podspec b/MBDataSource.podspec
index f3c00b2..94fd188 100644
--- a/MBDataSource.podspec
+++ b/MBDataSource.podspec
@@ -2,7 +2,7 @@ Pod::Spec.new do |s|
 
   # ―――  Spec Metadata  ―――――――――――――――――――――――――――――――――――――――――――――――――――――――――― #
   s.name        = "MBDataSource"
-  s.version     = "4.0.1"
+  s.version     = "5.0"
   s.summary     = "Simplifies the setup of UITableView data sources and cells using type-safe cell configurators."
   s.description = <<-DESC
                     Framework to simplify the setup of UITableView data sources and cells.
diff --git a/README.md b/README.md
index 6f441a5..81bbedd 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 # DataSource
 
-[![Swift 3](https://img.shields.io/badge/Language-Swift%203-orange.svg)](https://developer.apple.com/swift)
+[![Swift 4](https://img.shields.io/badge/Language-Swift%204-orange.svg)](https://developer.apple.com/swift)
 [![Carthage compatible](https://img.shields.io/badge/Carthage-compatible-brightgreen.svg)](https://github.com/Carthage/Carthage)
 [![CocoaPods compatible](https://img.shields.io/cocoapods/v/MBDataSource.svg)](https://cocoapods.org/pods/MBDataSource)
 [![CBuild status](https://travis-ci.org/mbuchetics/DataSource.svg?branch=master)](https://travis-ci.org/mbuchetics/DataSource)
@@ -225,6 +225,7 @@ Current Swift compatibility breakdown:
 
 | Swift Version | Framework Version |
 | ------------- | ----------------- |
+| 4.x           | 5.x                 |
 | 3.x           | 3.x, 4.x          |
 
 [all releases]: https://github.com/mbuchetics/DataSource/releases
@@ -236,7 +237,7 @@ Current Swift compatibility breakdown:
 Add the following line to your [Cartfile](https://github.com/Carthage/Carthage/blob/master/Documentation/Artifacts.md#cartfile).
 
 ```
-github "mbuchetics/DataSource", ~> 4.0
+github "mbuchetics/DataSource", ~> 5.0
 ```
 
 Then run `carthage update`.