diff --git a/.swift-version b/.swift-version
index 8c50098..7d5c902 100644
--- a/.swift-version
+++ b/.swift-version
@@ -1 +1 @@
-3.1
+4.1
diff --git a/.travis.yml b/.travis.yml
index 62d90ab..19e450e 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,9 +1,6 @@
 language: objective-c
 cache: cocoapods
-osx_image: xcode8.3
-before_install:
-  - brew uninstall carthage
-  - HOMEBREW_NO_AUTO_UPDATE=1 brew install https://raw.githubusercontent.com/Homebrew/homebrew-core/6ae4f69a652fb0ecb102b0c9216378679a4f1b92/Formula/carthage.rb # 0.22.0
+osx_image: xcode9.3
 branches:
   only:
     - master
diff --git a/Cartfile b/Cartfile
index 01d5496..58907e1 100644
--- a/Cartfile
+++ b/Cartfile
@@ -1,2 +1,2 @@
-github "ReactiveCocoa/ReactiveSwift" ~> 2.0
-github "ReactiveCocoa/ReactiveCocoa" ~> 6.0
+github "ReactiveCocoa/ReactiveSwift" ~> 3.1
+github "ReactiveCocoa/ReactiveCocoa" ~> 7.1
diff --git a/Cartfile.resolved b/Cartfile.resolved
index 5155c18..5adf965 100644
--- a/Cartfile.resolved
+++ b/Cartfile.resolved
@@ -1,6 +1,6 @@
-github "Quick/Nimble" "v7.0.1"
-github "Quick/Quick" "v1.1.0"
-github "ReactiveCocoa/ReactiveCocoa" "6.0.0"
-github "ReactiveCocoa/ReactiveSwift" "2.0.0"
-github "antitypical/Result" "3.2.3"
+github "Quick/Nimble" "v7.1.1"
+github "Quick/Quick" "v1.2.0"
+github "ReactiveCocoa/ReactiveCocoa" "7.2.0"
+github "ReactiveCocoa/ReactiveSwift" "3.1.0"
+github "antitypical/Result" "3.2.4"
 github "jspahrsummers/xcconfigs" "0.10"
diff --git a/Package.swift b/Package.swift
index a74c4d4..6775093 100644
--- a/Package.swift
+++ b/Package.swift
@@ -9,7 +9,7 @@ let package = Package(
     name: "ReactiveCollections",
     dependencies: {
         var deps: [Package.Dependency] = [
-	    .Package(url: "https://github.com/ReactiveCocoa/ReactiveSwift.git", majorVersion: 2),
+	    .Package(url: "https://github.com/ReactiveCocoa/ReactiveSwift.git", majorVersion: 3),
 	]
         if isSwiftPackagerManagerTest {
             deps += [
diff --git a/ReactiveCollections.podspec b/ReactiveCollections.podspec
index ff5d5bb..2f7d03a 100644
--- a/ReactiveCollections.podspec
+++ b/ReactiveCollections.podspec
@@ -14,6 +14,6 @@ Pod::Spec.new do |s|
 
   # Directory glob for all Swift files
   s.source_files  = "Sources/*.{swift}"
-  s.dependency 'ReactiveSwift', '~> 2.0'
-  s.dependency 'ReactiveCocoa', '~> 6.0'
+  s.dependency 'ReactiveSwift', '~> 3.1'
+  s.dependency 'ReactiveCocoa', '~> 7.1'
 end
diff --git a/ReactiveCollections.xcodeproj/project.pbxproj b/ReactiveCollections.xcodeproj/project.pbxproj
index dd81eb7..798059a 100644
--- a/ReactiveCollections.xcodeproj/project.pbxproj
+++ b/ReactiveCollections.xcodeproj/project.pbxproj
@@ -918,7 +918,7 @@
 				PRODUCT_NAME = ReactiveCollections;
 				SDKROOT = iphoneos;
 				SWIFT_ACTIVE_COMPILATION_CONDITIONS = DEBUG;
-				SWIFT_VERSION = 3.0;
+				SWIFT_VERSION = 4.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				TVOS_DEPLOYMENT_TARGET = 9.0;
 				VERSIONING_SYSTEM = "apple-generic";
@@ -973,7 +973,7 @@
 				PRODUCT_NAME = ReactiveCollections;
 				SDKROOT = iphoneos;
 				SWIFT_OPTIMIZATION_LEVEL = "-O";
-				SWIFT_VERSION = 3.0;
+				SWIFT_VERSION = 4.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				TVOS_DEPLOYMENT_TARGET = 9.0;
 				VALIDATE_PRODUCT = YES;
@@ -1296,7 +1296,7 @@
 				PRODUCT_NAME = ReactiveCollections;
 				SDKROOT = iphoneos;
 				SWIFT_ACTIVE_COMPILATION_CONDITIONS = DEBUG;
-				SWIFT_VERSION = 3.0;
+				SWIFT_VERSION = 4.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				TVOS_DEPLOYMENT_TARGET = 9.0;
 				VERSIONING_SYSTEM = "apple-generic";
@@ -1481,7 +1481,7 @@
 				PRODUCT_NAME = ReactiveCollections;
 				SDKROOT = iphoneos;
 				SWIFT_OPTIMIZATION_LEVEL = "-O";
-				SWIFT_VERSION = 3.0;
+				SWIFT_VERSION = 4.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				TVOS_DEPLOYMENT_TARGET = 9.0;
 				VALIDATE_PRODUCT = YES;
diff --git a/Sources/ReactiveArray.swift b/Sources/ReactiveArray.swift
index 89b7c4e..6b2e9c5 100644
--- a/Sources/ReactiveArray.swift
+++ b/Sources/ReactiveArray.swift
@@ -102,7 +102,7 @@ extension ReactiveArray {
 		public mutating func replaceSubrange<C>(_ subrange: Range<Int>, with newElements: C) where C: Collection, C.Iterator.Element == Element {
 			elements.replaceSubrange(subrange, with: newElements)
 
-			let elementsCount = Int(newElements.count.toIntMax())
+			let elementsCount = newElements.count
 
 			if subrange.count > elementsCount {
 				let deleteCount = subrange.count - elementsCount
diff --git a/script/build b/script/build
index 315cd1d..32ee62d 100755
--- a/script/build
+++ b/script/build
@@ -52,7 +52,7 @@ fi
 if [[ "$TRAVIS_XCODE_SCHEME" == "ReactiveCollections-tvOS" ]]; then
     XCODE_SDK=appletvsimulator
     XCODE_ACTION="build-for-testing test-without-building"
-    XCODE_DESTINATION="platform=tvOS Simulator,name=Apple TV 1080p"
+    XCODE_DESTINATION="platform=tvOS Simulator,name=Apple TV 4K (at 1080p)"
 fi
 
 if [[ "$TRAVIS_XCODE_SCHEME" == "ReactiveCollections-watchOS" ]]; then