diff --git a/BoltsSwift.xcodeproj/project.pbxproj b/BoltsSwift.xcodeproj/project.pbxproj
index 84ea537..673bc38 100644
--- a/BoltsSwift.xcodeproj/project.pbxproj
+++ b/BoltsSwift.xcodeproj/project.pbxproj
@@ -405,7 +405,7 @@
 			attributes = {
 				LastSwiftMigration = 0700;
 				LastSwiftUpdateCheck = 0700;
-				LastUpgradeCheck = 0700;
+				LastUpgradeCheck = 0800;
 				ORGANIZATIONNAME = Facebook;
 				TargetAttributes = {
 					065894E61C9A933B000FDDA6 = {
@@ -419,9 +419,11 @@
 					};
 					87FEF3651A9085FA00C60678 = {
 						CreatedOnToolsVersion = 6.3;
+						LastSwiftMigration = 0800;
 					};
 					87FEF3701A9085FA00C60678 = {
 						CreatedOnToolsVersion = 6.3;
+						LastSwiftMigration = 0800;
 					};
 				};
 			};
@@ -652,6 +654,7 @@
 				PRODUCT_NAME = BoltsSwift;
 				SDKROOT = watchos;
 				SKIP_INSTALL = YES;
+				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
 				TARGETED_DEVICE_FAMILY = 4;
 				WATCHOS_DEPLOYMENT_TARGET = 2.0;
 			};
@@ -695,6 +698,7 @@
 				PRODUCT_NAME = BoltsSwift;
 				SDKROOT = appletvos;
 				SKIP_INSTALL = YES;
+				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
 				TARGETED_DEVICE_FAMILY = 3;
 				TVOS_DEPLOYMENT_TARGET = 9.0;
 			};
@@ -728,6 +732,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = com.bolts.swift.tests.tvos;
 				PRODUCT_NAME = BoltsSwiftTests;
 				SDKROOT = appletvos;
+				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
 				TARGETED_DEVICE_FAMILY = 3;
 				TVOS_DEPLOYMENT_TARGET = 9.0;
 			};
@@ -779,6 +784,7 @@
 				PRODUCT_NAME = BoltsSwift;
 				SDKROOT = macosx;
 				SKIP_INSTALL = YES;
+				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
 			};
 			name = Release;
 		};
@@ -820,6 +826,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = com.bolts.swift.tests.osx;
 				PRODUCT_NAME = BoltsSwiftTests;
 				SDKROOT = macosx;
+				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
 			};
 			name = Release;
 		};
@@ -848,6 +855,7 @@
 				ENABLE_TESTABILITY = YES;
 				GCC_C_LANGUAGE_STANDARD = gnu99;
 				GCC_DYNAMIC_NO_PIC = NO;
+				GCC_NO_COMMON_BLOCKS = YES;
 				GCC_OPTIMIZATION_LEVEL = 0;
 				GCC_PREPROCESSOR_DEFINITIONS = (
 					"DEBUG=1",
@@ -895,6 +903,7 @@
 				ENABLE_NS_ASSERTIONS = NO;
 				ENABLE_STRICT_OBJC_MSGSEND = YES;
 				GCC_C_LANGUAGE_STANDARD = gnu99;
+				GCC_NO_COMMON_BLOCKS = YES;
 				GCC_WARN_64_TO_32_BIT_CONVERSION = YES;
 				GCC_WARN_ABOUT_RETURN_TYPE = YES_ERROR;
 				GCC_WARN_UNDECLARED_SELECTOR = YES;
@@ -928,6 +937,7 @@
 				PRODUCT_NAME = BoltsSwift;
 				SKIP_INSTALL = YES;
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
+				SWIFT_VERSION = 2.3;
 			};
 			name = Debug;
 		};
@@ -947,6 +957,8 @@
 				PRODUCT_BUNDLE_IDENTIFIER = com.bolts.swift.ios;
 				PRODUCT_NAME = BoltsSwift;
 				SKIP_INSTALL = YES;
+				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
+				SWIFT_VERSION = 2.3;
 			};
 			name = Release;
 		};
@@ -963,6 +975,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = com.bolts.swift.tests.ios;
 				PRODUCT_NAME = BoltsSwiftTests;
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
+				SWIFT_VERSION = 2.3;
 			};
 			name = Debug;
 		};
@@ -974,6 +987,8 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = com.bolts.swift.tests.ios;
 				PRODUCT_NAME = BoltsSwiftTests;
+				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
+				SWIFT_VERSION = 2.3;
 			};
 			name = Release;
 		};
diff --git a/BoltsSwift.xcodeproj/xcshareddata/xcschemes/BoltsSwift-OSX.xcscheme b/BoltsSwift.xcodeproj/xcshareddata/xcschemes/BoltsSwift-OSX.xcscheme
index eeb6d90..80a45f9 100644
--- a/BoltsSwift.xcodeproj/xcshareddata/xcschemes/BoltsSwift-OSX.xcscheme
+++ b/BoltsSwift.xcodeproj/xcshareddata/xcschemes/BoltsSwift-OSX.xcscheme
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "0730"
+   LastUpgradeVersion = "0800"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
@@ -11,8 +11,7 @@
             buildForRunning = "YES"
             buildForProfiling = "YES"
             buildForArchiving = "YES"
-            buildForAnalyzing = "YES"
-            hideIssues = "NO">
+            buildForAnalyzing = "YES">
             <BuildableReference
                BuildableIdentifier = "primary"
                BlueprintIdentifier = "81CC14EB1A9BE0A100B28F86"
diff --git a/BoltsSwift.xcodeproj/xcshareddata/xcschemes/BoltsSwift-iOS.xcscheme b/BoltsSwift.xcodeproj/xcshareddata/xcschemes/BoltsSwift-iOS.xcscheme
index 70cd548..e3cee89 100644
--- a/BoltsSwift.xcodeproj/xcshareddata/xcschemes/BoltsSwift-iOS.xcscheme
+++ b/BoltsSwift.xcodeproj/xcshareddata/xcschemes/BoltsSwift-iOS.xcscheme
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "0730"
+   LastUpgradeVersion = "0800"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
diff --git a/BoltsSwift.xcodeproj/xcshareddata/xcschemes/BoltsSwift-tvOS.xcscheme b/BoltsSwift.xcodeproj/xcshareddata/xcschemes/BoltsSwift-tvOS.xcscheme
index 65a0755..bfcbfaa 100644
--- a/BoltsSwift.xcodeproj/xcshareddata/xcschemes/BoltsSwift-tvOS.xcscheme
+++ b/BoltsSwift.xcodeproj/xcshareddata/xcschemes/BoltsSwift-tvOS.xcscheme
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "0720"
+   LastUpgradeVersion = "0800"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
diff --git a/BoltsSwift.xcodeproj/xcshareddata/xcschemes/BoltsSwift-watchOS.xcscheme b/BoltsSwift.xcodeproj/xcshareddata/xcschemes/BoltsSwift-watchOS.xcscheme
index c2333ca..722952f 100644
--- a/BoltsSwift.xcodeproj/xcshareddata/xcschemes/BoltsSwift-watchOS.xcscheme
+++ b/BoltsSwift.xcodeproj/xcshareddata/xcschemes/BoltsSwift-watchOS.xcscheme
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "0720"
+   LastUpgradeVersion = "0800"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
diff --git a/Tests/TaskTests.swift b/Tests/TaskTests.swift
index fea923c..f98b4e1 100644
--- a/Tests/TaskTests.swift
+++ b/Tests/TaskTests.swift
@@ -531,7 +531,8 @@ class TaskTests: XCTestCase {
         let executor = Executor.Queue(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0))
 
         tasks.append(Task<Void>.withDelay(0.2).continueWith { task in
-            return Int(rand())
+            // Use max value of Int32, so we can use the same code across both 32 and 64 bit archs.
+            return Int(arc4random_uniform(UInt32(Int32.max)))
         })
         for i in 1...20 {
             let task = Task<Void>.withDelay(0.5)