diff --git a/Bucketeer.xcodeproj/xcshareddata/xcschemes/Bucketeer.xcscheme b/Bucketeer.xcodeproj/xcshareddata/xcschemes/Bucketeer.xcscheme
index 7768d92d..4beea9ea 100644
--- a/Bucketeer.xcodeproj/xcshareddata/xcschemes/Bucketeer.xcscheme
+++ b/Bucketeer.xcodeproj/xcshareddata/xcschemes/Bucketeer.xcscheme
@@ -58,11 +58,6 @@
                BlueprintName = "BucketeerTests"
                ReferencedContainer = "container:Bucketeer.xcodeproj">
             </BuildableReference>
-            <SkippedTests>
-               <Test
-                  Identifier = "BucketeerE2ETests">
-               </Test>
-            </SkippedTests>
          </TestableReference>
       </Testables>
    </TestAction>
diff --git a/Bucketeer/Sources/Public/BKTClient.swift b/Bucketeer/Sources/Public/BKTClient.swift
index 46cbada2..10e069d6 100644
--- a/Bucketeer/Sources/Public/BKTClient.swift
+++ b/Bucketeer/Sources/Public/BKTClient.swift
@@ -108,6 +108,7 @@ extension BKTClient {
         BKTClient.default = nil
     }
 
+    // Please make sure the BKTClient is initialize before access it
     public static var shared: BKTClient {
         get throws {
             // We do not want to crash the SDK's consumer app on runtime by using fatalError().
diff --git a/BucketeerTests/E2E/BucketeerE2ETests.swift b/BucketeerTests/E2E/BucketeerE2ETests.swift
index 548622e5..9eeda366 100644
--- a/BucketeerTests/E2E/BucketeerE2ETests.swift
+++ b/BucketeerTests/E2E/BucketeerE2ETests.swift
@@ -25,18 +25,18 @@ final class BucketeerE2ETests: XCTestCase {
         try await super.tearDown()
 
         try await BKTClient.shared.flush()
-        BKTClient.destroy()
+        try! BKTClient.destroy()
         UserDefaults.standard.removeObject(forKey: "bucketeer_user_evaluations_id")
         try FileManager.default.removeItem(at: .database)
     }
 
     func testStringVariation() {
-        let client = BKTClient.shared
+        let client = try! BKTClient.shared
         XCTAssertEqual(client.stringVariation(featureId: FEATURE_ID_STRING, defaultValue: ""), "value-1")
     }
 
     func testStringVariationDetail() {
-        let client = BKTClient.shared
+        let client = try! BKTClient.shared
         let actual = client.evaluationDetails(featureId: FEATURE_ID_STRING)
 
         assertEvaluation(actual: actual, expected: .init(
@@ -51,12 +51,12 @@ final class BucketeerE2ETests: XCTestCase {
     }
 
     func testIntVariation() {
-        let client = BKTClient.shared
+        let client = try! BKTClient.shared
         XCTAssertEqual(client.intVariation(featureId: FEATURE_ID_INT, defaultValue: 0), 10)
     }
 
     func testIntVariationDetail() {
-        let client = BKTClient.shared
+        let client = try! BKTClient.shared
         let actual = client.evaluationDetails(featureId: FEATURE_ID_INT)
 
         assertEvaluation(actual: actual, expected: .init(
@@ -71,12 +71,12 @@ final class BucketeerE2ETests: XCTestCase {
     }
 
     func testDoubleVariation() {
-        let client = BKTClient.shared
+        let client = try! BKTClient.shared
         XCTAssertEqual(client.doubleVariation(featureId: FEATURE_ID_DOUBLE, defaultValue: 0.1), 2.1)
     }
 
     func testDoubleVariationDetail() async throws {
-        let client = BKTClient.shared
+        let client = try! BKTClient.shared
         let actual = client.evaluationDetails(featureId: FEATURE_ID_DOUBLE)
 
         assertEvaluation(actual: actual, expected: .init(
@@ -91,12 +91,12 @@ final class BucketeerE2ETests: XCTestCase {
     }
 
     func testBoolVariation() {
-        let client = BKTClient.shared
+        let client = try! BKTClient.shared
         XCTAssertEqual(client.boolVariation(featureId: FEATURE_ID_BOOLEAN, defaultValue: false), true)
     }
 
     func testBoolVariationDetail() {
-        let client = BKTClient.shared
+        let client = try! BKTClient.shared
         let actual = client.evaluationDetails(featureId: FEATURE_ID_BOOLEAN)
 
         assertEvaluation(actual: actual, expected: .init(
@@ -111,13 +111,13 @@ final class BucketeerE2ETests: XCTestCase {
     }
 
     func testJSONVariation() {
-        let client = BKTClient.shared
+        let client = try! BKTClient.shared
         let json = client.jsonVariation(featureId: FEATURE_ID_JSON, defaultValue: [:])
         XCTAssertEqual(json as? [String: String], ["key": "value-1"])
     }
 
     func testJSONVariationDetail() {
-        let client = BKTClient.shared
+        let client = try! BKTClient.shared
         let actual = client.evaluationDetails(featureId: FEATURE_ID_JSON)
 
         assertEvaluation(actual: actual, expected: .init(
@@ -132,7 +132,7 @@ final class BucketeerE2ETests: XCTestCase {
     }
 
     func testEvaluationUpdateFlow() async throws {
-        let client = BKTClient.shared
+        let client = try! BKTClient.shared
         XCTAssertEqual(client.stringVariation(featureId: FEATURE_ID_STRING, defaultValue: ""), "value-1")
 
         client.updateUserAttributes(attributes: ["app_version": "0.0.1"])
@@ -153,7 +153,7 @@ final class BucketeerE2ETests: XCTestCase {
     }
 
     func testTrack() async throws {
-        let client = BKTClient.shared
+        let client = try! BKTClient.shared
         client.assert(expectedEventCount: 2)
         client.track(goalId: GOAL_ID, value: GOAL_VALUE)
         try await Task.sleep(nanoseconds: 1_000_000)
diff --git a/BucketeerTests/E2E/E2ETestHelpers.swift b/BucketeerTests/E2E/E2ETestHelpers.swift
index 7cb922da..38668627 100644
--- a/BucketeerTests/E2E/E2ETestHelpers.swift
+++ b/BucketeerTests/E2E/E2ETestHelpers.swift
@@ -35,7 +35,7 @@ extension BKTClient {
     static func initialize(config: BKTConfig, user: BKTUser, timeoutMillis: Int64 = 5000) async throws {
         return try await withCheckedThrowingContinuation { continuation in
             DispatchQueue.main.async {
-                self.initialize(config: config, user: user) { error in
+                try! self.initialize(config: config, user: user) { error in
                     if let error = error {
                         continuation.resume(throwing: error)
                     } else {