diff --git a/ObjectMapper.xcodeproj/project.pbxproj b/ObjectMapper.xcodeproj/project.pbxproj
index 8e6e8c6d..329a283b 100644
--- a/ObjectMapper.xcodeproj/project.pbxproj
+++ b/ObjectMapper.xcodeproj/project.pbxproj
@@ -728,11 +728,11 @@
 					};
 					6AAC8F7519F03C2900E7A677 = {
 						CreatedOnToolsVersion = 6.0.1;
-						LastSwiftMigration = 0900;
+						LastSwiftMigration = 1120;
 					};
 					6AAC8F8019F03C2900E7A677 = {
 						CreatedOnToolsVersion = 6.0.1;
-						LastSwiftMigration = 0900;
+						LastSwiftMigration = 1120;
 					};
 					CD1602FE1AC023D5000CD69A = {
 						CreatedOnToolsVersion = 6.2;
@@ -1108,7 +1108,7 @@
 				PRODUCT_NAME = "$(PROJECT_NAME)";
 				SDKROOT = appletvos;
 				SKIP_INSTALL = YES;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = 3;
 				TVOS_DEPLOYMENT_TARGET = 9.0;
 				WATCHOS_DEPLOYMENT_TARGET = 2.0;
@@ -1137,7 +1137,7 @@
 				PRODUCT_NAME = "$(PROJECT_NAME)";
 				SDKROOT = appletvos;
 				SKIP_INSTALL = YES;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = 3;
 				TVOS_DEPLOYMENT_TARGET = 9.0;
 				WATCHOS_DEPLOYMENT_TARGET = 2.0;
@@ -1156,7 +1156,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = "com.tristanhimmelman.ObjectMapper-tvOSTests";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SDKROOT = appletvos;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 				TVOS_DEPLOYMENT_TARGET = 9.0;
 			};
 			name = Debug;
@@ -1174,7 +1174,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = "com.tristanhimmelman.ObjectMapper-tvOSTests";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SDKROOT = appletvos;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 				TVOS_DEPLOYMENT_TARGET = 9.0;
 			};
 			name = Release;
@@ -1200,7 +1200,7 @@
 				PRODUCT_NAME = "$(PROJECT_NAME)";
 				SDKROOT = watchos;
 				SKIP_INSTALL = YES;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = 4;
 				TVOS_DEPLOYMENT_TARGET = 9.0;
 				WATCHOS_DEPLOYMENT_TARGET = 2.0;
@@ -1228,7 +1228,7 @@
 				PRODUCT_NAME = "$(PROJECT_NAME)";
 				SDKROOT = watchos;
 				SKIP_INSTALL = YES;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = 4;
 				TVOS_DEPLOYMENT_TARGET = 9.0;
 				WATCHOS_DEPLOYMENT_TARGET = 2.0;
@@ -1363,8 +1363,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = "com.tristanhimmelman.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(PROJECT_NAME)";
 				SKIP_INSTALL = YES;
-				SWIFT_SWIFT3_OBJC_INFERENCE = Default;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 				TVOS_DEPLOYMENT_TARGET = 9.0;
 				WATCHOS_DEPLOYMENT_TARGET = 2.0;
 			};
@@ -1385,8 +1384,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = "com.tristanhimmelman.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(PROJECT_NAME)";
 				SKIP_INSTALL = YES;
-				SWIFT_SWIFT3_OBJC_INFERENCE = Default;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 				TVOS_DEPLOYMENT_TARGET = 9.0;
 				WATCHOS_DEPLOYMENT_TARGET = 2.0;
 			};
@@ -1404,8 +1402,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = "com.heart.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_SWIFT3_OBJC_INFERENCE = Default;
-				SWIFT_VERSION = 4.0;
+				SWIFT_VERSION = 5.0;
 			};
 			name = Debug;
 		};
@@ -1417,8 +1414,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = "com.heart.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_SWIFT3_OBJC_INFERENCE = Default;
-				SWIFT_VERSION = 4.0;
+				SWIFT_VERSION = 5.0;
 			};
 			name = Release;
 		};
@@ -1446,7 +1442,7 @@
 				PRODUCT_NAME = "$(PROJECT_NAME)";
 				SDKROOT = macosx;
 				SKIP_INSTALL = YES;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 				TVOS_DEPLOYMENT_TARGET = 9.0;
 				WATCHOS_DEPLOYMENT_TARGET = 2.0;
 			};
@@ -1474,7 +1470,7 @@
 				PRODUCT_NAME = "$(PROJECT_NAME)";
 				SDKROOT = macosx;
 				SKIP_INSTALL = YES;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 				TVOS_DEPLOYMENT_TARGET = 9.0;
 				WATCHOS_DEPLOYMENT_TARGET = 2.0;
 			};
@@ -1495,7 +1491,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = "com.heart.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SDKROOT = macosx;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 			};
 			name = Debug;
 		};
@@ -1512,7 +1508,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = "com.heart.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SDKROOT = macosx;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 			};
 			name = Release;
 		};
@@ -1536,7 +1532,7 @@
 				PRODUCT_NAME = ObjectMapper;
 				SDKROOT = macosx;
 				SKIP_INSTALL = YES;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 			};
 			name = Debug;
 		};
@@ -1561,7 +1557,7 @@
 				PRODUCT_NAME = ObjectMapper;
 				SDKROOT = macosx;
 				SKIP_INSTALL = YES;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 			};
 			name = Release;
 		};
diff --git a/ObjectMapper.xcworkspace/xcshareddata/IDEWorkspaceChecks.plist b/ObjectMapper.xcworkspace/xcshareddata/IDEWorkspaceChecks.plist
new file mode 100644
index 00000000..18d98100
--- /dev/null
+++ b/ObjectMapper.xcworkspace/xcshareddata/IDEWorkspaceChecks.plist
@@ -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>IDEDidComputeMac32BitWarning</key>
+	<true/>
+</dict>
+</plist>
diff --git a/Tests/ObjectMapperTests/ImmutableTests.swift b/Tests/ObjectMapperTests/ImmutableTests.swift
index bafba916..f722add1 100644
--- a/Tests/ObjectMapperTests/ImmutableTests.swift
+++ b/Tests/ObjectMapperTests/ImmutableTests.swift
@@ -201,12 +201,12 @@ class ImmutableObjectTests: XCTestCase {
 		XCTAssertEqual(immutable.delimiterNestedDictionary, ["a": 10, "b": 20, "c": 30])
 		
 		let JSON2: [String: Any] = [ "prop1": "prop1", "prop2": NSNull() ]
-		let immutable2 = try? mapper.map(JSON: JSON2)
+		let immutable2 = try? mapper.map(JSON: JSON2) as Struct
 		XCTAssertNil(immutable2)
 		
 		// TODO: ImmutableMappable to JSON
 		let JSONFromObject = mapper.toJSON(immutable)
-		let objectFromJSON = try? mapper.map(JSON: JSONFromObject)
+		let objectFromJSON = try? mapper.map(JSON: JSONFromObject) as Struct
 		XCTAssertNotNil(objectFromJSON)
 		assertImmutableObjectsEqual(objectFromJSON!, immutable)
 	}
diff --git a/Tests/ObjectMapperTests/MapContextTests.swift b/Tests/ObjectMapperTests/MapContextTests.swift
index bc6c4ace..3bf4e250 100644
--- a/Tests/ObjectMapperTests/MapContextTests.swift
+++ b/Tests/ObjectMapperTests/MapContextTests.swift
@@ -138,7 +138,7 @@ class MapContextTests: XCTestCase {
 		let JSON = ["name": "Anton"]
 		let context = ImmutableContext(isDeveloper: true)
 		
-		let person = try? Mapper<ImmutablePerson>(context: context).map(JSON: JSON)
+		let person = try? Mapper<ImmutablePerson>(context: context).map(JSON: JSON) as ImmutablePerson
 		
 		XCTAssertNotNil(person)
 		
@@ -149,7 +149,7 @@ class MapContextTests: XCTestCase {
 		let JSON = ["name": "Anton"]
 		let context = ImmutableContext(isDeveloper: true)
 		
-		let person = try? ImmutablePerson(JSON: JSON, context: context)
+		let person = try? ImmutablePerson(JSON: JSON, context: context) as ImmutablePerson
 		
 		XCTAssertNotNil(person)
 		XCTAssertEqual(person?.isDeveloper ?? !context.isDeveloper, context.isDeveloper)
@@ -172,7 +172,7 @@ class MapContextTests: XCTestCase {
 		let JSON = ["person": ["name": "Anton"]]
 		let context = ImmutableContext(isDeveloper: true)
 		
-		let nestedPerson = try? Mapper<ImmutableNestedPerson>(context: context).map(JSON: JSON)
+		let nestedPerson = try? Mapper<ImmutableNestedPerson>(context: context).map(JSON: JSON) as ImmutableNestedPerson
 		
 		XCTAssertNotNil(nestedPerson)
 		XCTAssertEqual(nestedPerson?.person.isDeveloper ?? !context.isDeveloper, context.isDeveloper)
@@ -182,7 +182,7 @@ class MapContextTests: XCTestCase {
 		let JSON = ["person": ["name": "Anton"]]
 		let context = ImmutableContext(isDeveloper: true)
 		
-		let nestedPerson = try? ImmutableNestedPerson(JSON: JSON, context: context)
+		let nestedPerson = try? ImmutableNestedPerson(JSON: JSON, context: context) as ImmutableNestedPerson
 		
 		XCTAssertNotNil(nestedPerson)
 		XCTAssertEqual(nestedPerson?.person.isDeveloper ?? !context.isDeveloper, context.isDeveloper)
@@ -207,7 +207,7 @@ class MapContextTests: XCTestCase {
 		let JSON = ["persons": [["name": "Tristan"], ["name": "Anton"]]]
 		let context = ImmutableContext(isDeveloper: true)
 		
-		let personList = try? Mapper<ImmutablePersonList>(context: context).map(JSON: JSON)
+		let personList = try? Mapper<ImmutablePersonList>(context: context).map(JSON: JSON) as ImmutablePersonList
 		
 		XCTAssertNotNil(personList)
 		
@@ -220,7 +220,7 @@ class MapContextTests: XCTestCase {
 		let JSON = ["persons": [["name": "Tristan"], ["name": "Anton"]]]
 		let context = ImmutableContext(isDeveloper: true)
 		
-		let personList = try? ImmutablePersonList(JSON: JSON, context: context)
+		let personList = try? ImmutablePersonList(JSON: JSON, context: context) as ImmutablePersonList
 		
 		XCTAssertNotNil(personList)
 		
diff --git a/Tests/ObjectMapperTests/MappableExtensionsTests.swift b/Tests/ObjectMapperTests/MappableExtensionsTests.swift
index b885cf1f..d3ee7960 100644
--- a/Tests/ObjectMapperTests/MappableExtensionsTests.swift
+++ b/Tests/ObjectMapperTests/MappableExtensionsTests.swift
@@ -44,12 +44,14 @@ struct TestMappable: Mappable, Equatable, Hashable {
 	mutating func mapping(map: Map) {
 		value <- map["value"]
 	}
-	
-	var hashValue: Int {
+
+
+	func hash(into hasher: inout Hasher) {
 		if let value = value {
-			return value.hashValue
+			hasher.combine(value)
+		} else {
+			hasher.combine(NSIntegerMax)
 		}
-		return NSIntegerMax
 	}
 }
 
diff --git a/Tests/ObjectMapperTests/PerformanceTests.swift b/Tests/ObjectMapperTests/PerformanceTests.swift
index 6e0620ba..fa2819be 100644
--- a/Tests/ObjectMapperTests/PerformanceTests.swift
+++ b/Tests/ObjectMapperTests/PerformanceTests.swift
@@ -71,7 +71,7 @@ class PerformanceTests: XCTestCase {
 	
 	func testPerformanceImmutable() {
 		self.measure {
-			_ = try? Mapper<PerformanceImmutableMappableObject>().mapArray(JSONString: self.JSONTestString)
+			_ = try? Mapper<PerformanceImmutableMappableObject>().mapArray(JSONString: self.JSONTestString) as [PerformanceImmutableMappableObject]
 		}
 	}
 }