diff --git a/Source/Sync/NSManagedObject+Sync.swift b/Source/Sync/NSManagedObject+Sync.swift
index 9a956961..4d8c7edc 100644
--- a/Source/Sync/NSManagedObject+Sync.swift
+++ b/Source/Sync/NSManagedObject+Sync.swift
@@ -14,7 +14,7 @@ extension NSManagedObject {
     func sync_copyInContext(_ context: NSManagedObjectContext) -> NSManagedObject {
         guard let entityName = self.entity.name else { fatalError("Couldn't find entity name") }
         let localPrimaryKey = value(forKey: self.entity.sync_localPrimaryKey())
-        guard let copiedObject = context.safeObject(entityName, localPrimaryKey: localPrimaryKey, parent: nil, parentRelationshipName: nil) else { fatalError("Couldn't fetch a safe object from entityName: \(entityName) localPrimaryKey: \(localPrimaryKey)") }
+        guard let copiedObject = context.safeObject(entityName, localPrimaryKey: localPrimaryKey, parent: nil, parentRelationshipName: nil) else { fatalError("Couldn't fetch a safe object from entityName: \(entityName) localPrimaryKey: \(String(describing: localPrimaryKey))") }
 
         return copiedObject
     }
diff --git a/Source/Sync/NSManagedObjectContext+Sync.swift b/Source/Sync/NSManagedObjectContext+Sync.swift
index 93dbec8a..859f1cd6 100644
--- a/Source/Sync/NSManagedObjectContext+Sync.swift
+++ b/Source/Sync/NSManagedObjectContext+Sync.swift
@@ -20,7 +20,7 @@ public extension NSManagedObjectContext {
                 let objects = try fetch(request)
                 result = objects.first as? NSManagedObject
             } catch {
-                fatalError("Failed to fetch request for entityName: \(entityName), predicate: \(request.predicate)")
+                fatalError("Failed to fetch request for entityName: \(entityName), predicate: \(String(describing: request.predicate))")
             }
         } else if let parentRelationshipName = parentRelationshipName {
             // More info: https://github.com/SyncDB/Sync/pull/72
diff --git a/Tests/DateParser/DateTests.swift b/Tests/DateParser/DateTests.swift
index 751e1dd6..6c112bd7 100755
--- a/Tests/DateParser/DateTests.swift
+++ b/Tests/DateParser/DateTests.swift
@@ -5,7 +5,7 @@ class DateTests: XCTestCase {
 
     func testDateA() {
         let date = Date.dateWithHourAndTimeZoneString(dateString: "2015-06-23T12:40:08.000")
-        let resultDate = NSDate(fromDateString: "2015-06-23T14:40:08.000+02:00") as! Date
+        let resultDate = NSDate(fromDateString: "2015-06-23T14:40:08.000+02:00")! as Date
 
         XCTAssertNotNil(resultDate)
         XCTAssertEqual(date.timeIntervalSince1970, resultDate.timeIntervalSince1970)
@@ -13,7 +13,7 @@ class DateTests: XCTestCase {
 
     func testDateB() {
         let date = Date.dateWithDayString(dateString: "2014-01-01")
-        let resultDate = NSDate(fromDateString: "2014-01-01T00:00:00+00:00") as! Date
+        let resultDate = NSDate(fromDateString: "2014-01-01T00:00:00+00:00")! as Date
 
         XCTAssertNotNil(resultDate)
         XCTAssertEqual(date, resultDate)
@@ -21,7 +21,7 @@ class DateTests: XCTestCase {
 
     func testDateC() {
         let date = Date.dateWithDayString(dateString: "2014-01-02")
-        let resultDate = NSDate(fromDateString: "2014-01-02") as! Date
+        let resultDate = NSDate(fromDateString: "2014-01-02")! as Date
 
         XCTAssertNotNil(resultDate)
         XCTAssertEqual(date, resultDate)
@@ -29,7 +29,7 @@ class DateTests: XCTestCase {
 
     func testDateD() {
         let date = Date.dateWithDayString(dateString: "2014-01-02")
-        let resultDate = NSDate(fromDateString: "2014-01-02T00:00:00.000000+00:00") as! Date
+        let resultDate = NSDate(fromDateString: "2014-01-02T00:00:00.000000+00:00")! as Date
 
         XCTAssertNotNil(resultDate)
         XCTAssertEqual(date, resultDate)
@@ -37,7 +37,7 @@ class DateTests: XCTestCase {
 
     func testDateE() {
         let date = Date.dateWithDayString(dateString: "2015-09-10")
-        let resultDate = NSDate(fromDateString: "2015-09-10T00:00:00.116+0000") as! Date
+        let resultDate = NSDate(fromDateString: "2015-09-10T00:00:00.116+0000")! as Date
 
         XCTAssertNotNil(resultDate)
         XCTAssertEqual(date, resultDate)
@@ -45,7 +45,7 @@ class DateTests: XCTestCase {
 
     func testDateF() {
         let date = Date.dateWithDayString(dateString: "2015-09-10")
-        let resultDate = NSDate(fromDateString: "2015-09-10T00:00:00.184968Z") as! Date
+        let resultDate = NSDate(fromDateString: "2015-09-10T00:00:00.184968Z")! as Date
 
         XCTAssertNotNil(resultDate)
         XCTAssertEqual(date, resultDate)
@@ -53,7 +53,7 @@ class DateTests: XCTestCase {
 
     func testDateG() {
         let date = Date.dateWithHourAndTimeZoneString(dateString: "2015-06-23T19:04:19.911Z")
-        let resultDate = NSDate(fromDateString: "2015-06-23T19:04:19.911Z") as! Date
+        let resultDate = NSDate(fromDateString: "2015-06-23T19:04:19.911Z")! as Date
         print(date.timeIntervalSince1970)
         print(resultDate.timeIntervalSince1970)
         date.prettyPrint()
@@ -64,7 +64,7 @@ class DateTests: XCTestCase {
 
     func testDateH() {
         let date = Date.dateWithHourAndTimeZoneString(dateString: "2014-03-30T09:13:00.000Z")
-        let resultDate = NSDate(fromDateString: "2014-03-30T09:13:00Z") as! Date
+        let resultDate = NSDate(fromDateString: "2014-03-30T09:13:00Z")! as Date
         XCTAssertNotNil(resultDate)
         XCTAssertEqual(date, resultDate)
     }
@@ -76,21 +76,21 @@ class DateTests: XCTestCase {
 
     func testDateJ() {
         let date = Date.dateWithDayString(dateString: "2016-01-09")
-        let resultDate = NSDate(fromDateString: "2016-01-09T00:00:00.00") as! Date
+        let resultDate = NSDate(fromDateString: "2016-01-09T00:00:00.00")! as Date
         XCTAssertNotNil(resultDate)
         XCTAssertEqual(date, resultDate)
     }
 
     func testDateK() {
         let date = Date.dateWithDayString(dateString: "2016-01-09")
-        let resultDate = NSDate(fromDateString: "2016-01-09T00:00:00") as! Date
+        let resultDate = NSDate(fromDateString: "2016-01-09T00:00:00")! as Date
         XCTAssertNotNil(resultDate)
         XCTAssertEqual(date, resultDate)
     }
 
     func testDateL() {
         let date = Date.dateWithDayString(dateString: "2009-10-09")
-        let resultDate = NSDate(fromDateString: "2009-10-09 00:00:00") as! Date
+        let resultDate = NSDate(fromDateString: "2009-10-09 00:00:00")! as Date
         XCTAssertNotNil(resultDate)
         XCTAssertEqual(date, resultDate)
     }
@@ -100,7 +100,7 @@ class TimestampDateTests: XCTestCase {
 
     func testTimestampA() {
         let date = Date.dateWithDayString(dateString: "2015-09-10")
-        let resultDate = NSDate(fromDateString: "1441843200") as! Date
+        let resultDate = NSDate(fromDateString: "1441843200")! as Date
 
         XCTAssertNotNil(resultDate)
         XCTAssertEqual(date, resultDate)
@@ -108,7 +108,7 @@ class TimestampDateTests: XCTestCase {
 
     func testTimestampB() {
         let date = Date.dateWithDayString(dateString: "2015-09-10")
-        let resultDate = NSDate(fromDateString: "1441843200000000") as! Date
+        let resultDate = NSDate(fromDateString: "1441843200000000")! as Date
 
         XCTAssertNotNil(resultDate)
         XCTAssertEqual(date, resultDate)
@@ -116,7 +116,7 @@ class TimestampDateTests: XCTestCase {
 
     func testTimestampC() {
         let date = Date.dateWithDayString(dateString: "2015-09-10")
-        let resultDate = NSDate(fromUnixTimestampNumber: 1441843200) as! Date
+        let resultDate = NSDate(fromUnixTimestampNumber: 1441843200)! as Date
 
         XCTAssertNotNil(resultDate)
         XCTAssertEqual(date, resultDate)
@@ -124,7 +124,7 @@ class TimestampDateTests: XCTestCase {
 
     func testTimestampD() {
         let date = Date.dateWithDayString(dateString: "2015-09-10")
-        let resultDate = NSDate(fromUnixTimestampNumber: NSNumber(value: 1441843200000000.0)) as! Date
+        let resultDate = NSDate(fromUnixTimestampNumber: NSNumber(value: 1441843200000000.0))! as Date
 
         XCTAssertNotNil(resultDate)
         XCTAssertEqual(date, resultDate)