diff --git a/Tests/web3swiftTests/localTests/EthereumContractTest.swift b/Tests/web3swiftTests/localTests/EthereumContractTest.swift
index 6031e0e84..06251e388 100644
--- a/Tests/web3swiftTests/localTests/EthereumContractTest.swift
+++ b/Tests/web3swiftTests/localTests/EthereumContractTest.swift
@@ -17,8 +17,8 @@ class EthereumContractTest: LocalTestCase {
     private static let overloadedFunctionsABI = "[{\"inputs\":[],\"stateMutability\":\"nonpayable\",\"type\":\"constructor\"},{\"anonymous\":false,\"inputs\":[{\"indexed\":true,\"internalType\":\"uint256\",\"name\":\"operation\",\"type\":\"uint256\"},{\"indexed\":true,\"internalType\":\"address\",\"name\":\"contractAddress\",\"type\":\"address\"},{\"indexed\":true,\"internalType\":\"uint256\",\"name\":\"value\",\"type\":\"uint256\"}],\"name\":\"ContractCreated\",\"type\":\"event\"},{\"anonymous\":false,\"inputs\":[{\"indexed\":true,\"internalType\":\"bytes32\",\"name\":\"dataKey\",\"type\":\"bytes32\"}],\"name\":\"DataChanged\",\"type\":\"event\"},{\"anonymous\":false,\"inputs\":[{\"indexed\":true,\"internalType\":\"uint256\",\"name\":\"operation\",\"type\":\"uint256\"},{\"indexed\":true,\"internalType\":\"address\",\"name\":\"to\",\"type\":\"address\"},{\"indexed\":true,\"internalType\":\"uint256\",\"name\":\"value\",\"type\":\"uint256\"},{\"indexed\":false,\"internalType\":\"bytes4\",\"name\":\"selector\",\"type\":\"bytes4\"}],\"name\":\"Executed\",\"type\":\"event\"},{\"anonymous\":false,\"inputs\":[{\"indexed\":true,\"internalType\":\"address\",\"name\":\"previousOwner\",\"type\":\"address\"},{\"indexed\":true,\"internalType\":\"address\",\"name\":\"newOwner\",\"type\":\"address\"}],\"name\":\"OwnershipTransferred\",\"type\":\"event\"},{\"anonymous\":false,\"inputs\":[{\"indexed\":true,\"internalType\":\"address\",\"name\":\"from\",\"type\":\"address\"},{\"indexed\":false,\"internalType\":\"uint256\",\"name\":\"value\",\"type\":\"uint256\"},{\"indexed\":true,\"internalType\":\"bytes32\",\"name\":\"typeId\",\"type\":\"bytes32\"},{\"indexed\":true,\"internalType\":\"bytes\",\"name\":\"returnedValue\",\"type\":\"bytes\"},{\"indexed\":false,\"internalType\":\"bytes\",\"name\":\"receivedData\",\"type\":\"bytes\"}],\"name\":\"UniversalReceiver\",\"type\":\"event\"},{\"anonymous\":false,\"inputs\":[{\"indexed\":true,\"internalType\":\"address\",\"name\":\"sender\",\"type\":\"address\"},{\"indexed\":true,\"internalType\":\"uint256\",\"name\":\"value\",\"type\":\"uint256\"}],\"name\":\"ValueReceived\",\"type\":\"event\"},{\"stateMutability\":\"payable\",\"type\":\"fallback\"},{\"inputs\":[{\"internalType\":\"bytes32[]\",\"name\":\"dataKeys\",\"type\":\"bytes32[]\"}],\"name\":\"getData\",\"outputs\":[{\"internalType\":\"bytes[]\",\"name\":\"dataValues\",\"type\":\"bytes[]\"}],\"stateMutability\":\"view\",\"type\":\"function\"},{\"inputs\":[{\"internalType\":\"bytes32\",\"name\":\"dataKey\",\"type\":\"bytes32\"}],\"name\":\"getData\",\"outputs\":[{\"internalType\":\"bytes\",\"name\":\"dataValue\",\"type\":\"bytes\"}],\"stateMutability\":\"view\",\"type\":\"function\"},{\"inputs\":[],\"name\":\"noInputFunction\",\"outputs\":[],\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"inputs\":[{\"internalType\":\"bytes32[]\",\"name\":\"dataKeys\",\"type\":\"bytes32[]\"},{\"internalType\":\"bytes[]\",\"name\":\"dataValues\",\"type\":\"bytes[]\"}],\"name\":\"setData\",\"outputs\":[],\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"inputs\":[{\"internalType\":\"bytes32\",\"name\":\"dataKey\",\"type\":\"bytes32\"},{\"internalType\":\"bytes\",\"name\":\"dataValue\",\"type\":\"bytes\"}],\"name\":\"setData\",\"outputs\":[],\"stateMutability\":\"nonpayable\",\"type\":\"function\"}]"
 
     func test_decodeEvents() async throws {
-        let web3 = try! await Web3.new(LocalTestCase.url)
-        let contract = web3.contract(EthereumContractTest.eventsOnlyABI)!
+        let web3 = try await Web3.new(LocalTestCase.url)
+        let contract = try XCTUnwrap(web3.contract(EthereumContractTest.eventsOnlyABI))
 
         XCTAssertTrue(contract.contract.allEvents.count == 6)
         XCTAssertNotNil(contract.contract.events["ContractCreated"])
@@ -30,8 +30,8 @@ class EthereumContractTest: LocalTestCase {
     }
 
     func test_decodedAllFunctions() async throws {
-        let web3 = try! await Web3.new(LocalTestCase.url)
-        let contract = web3.contract(EthereumContractTest.overloadedFunctionsABI)!
+        let web3 = try await Web3.new(LocalTestCase.url)
+        let contract = try XCTUnwrap(web3.contract(EthereumContractTest.overloadedFunctionsABI))
 
         XCTAssertTrue(contract.contract.allMethods.count == 5)
 
@@ -53,8 +53,8 @@ class EthereumContractTest: LocalTestCase {
     }
 
     func test_encodeMethodBasedOnNameWithParameters_mustFail() async throws {
-        let web3 = try! await Web3.new(LocalTestCase.url)
-        let contract = web3.contract(EthereumContractTest.overloadedFunctionsABI)!
+        let web3 = try await Web3.new(LocalTestCase.url)
+        let contract = try XCTUnwrap(web3.contract(EthereumContractTest.overloadedFunctionsABI))
 
         /// Encoding method that expects parameters but we are not giving any.
         /// Result must be `nil`.
@@ -63,43 +63,41 @@ class EthereumContractTest: LocalTestCase {
     }
 
     func test_encodeMethodBasedOnNameWithParameters() async throws {
-        let web3 = try! await Web3.new(LocalTestCase.url)
-        let contract = web3.contract(EthereumContractTest.overloadedFunctionsABI,
-                                        at: EthereumAddress("0x6394b37Cf80A7358b38068f0CA4760ad49983a1B")!)!
+        let web3 = try await Web3.new(LocalTestCase.url)
+        let contract = try XCTUnwrap(web3.contract(EthereumContractTest.overloadedFunctionsABI, at: EthereumAddress("0x6394b37Cf80A7358b38068f0CA4760ad49983a1B")))
         let parameters: [AnyObject] = [
-            [Data.randomBytes(length: 32)!,
-             Data.randomBytes(length: 32)!],
-            [Data.randomBytes(length: 32)!,
-             Data.randomBytes(length: 32)!]
+            [Data.randomBytes(length: 32), Data.randomBytes(length: 32)],
+            [Data.randomBytes(length: 32), Data.randomBytes(length: 32)]
         ] as [AnyObject]
         let functionNameWithParameters = "setData(bytes32[],bytes[])"
         let transaction = contract.createWriteOperation(functionNameWithParameters, parameters: parameters)
         XCTAssertNotNil(transaction)
 
-        func testDecoding(_ method: String) {
-            let decodedData = contract.contract.methods[method]?.first?.decodeInputData(transaction!.transaction.data)
+        func testDecoding(_ method: String) throws {
+            let data = try XCTUnwrap(transaction?.transaction.data)
+            let decodedData = try XCTUnwrap(contract.contract.methods[method]?.first?.decodeInputData(data))
             XCTAssertNotNil(decodedData)
-            XCTAssertEqual(decodedData!["0"] as! [Data], parameters[0] as! [Data])
-            XCTAssertEqual(decodedData!["1"] as! [Data], parameters[1] as! [Data])
+            XCTAssertEqual(try XCTUnwrap(decodedData["0"] as? [Data]), try XCTUnwrap(parameters[0] as? [Data]))
+            XCTAssertEqual(try XCTUnwrap(decodedData["1"] as? [Data]), try XCTUnwrap(parameters[1] as? [Data]))
         }
 
-        testDecoding(functionNameWithParameters)
-        testDecoding(getFuncSignature(functionNameWithParameters))
+        try testDecoding(functionNameWithParameters)
+        try testDecoding(getFuncSignature(functionNameWithParameters))
     }
 
     func test_encodeMethodBasedOnHexSignature() async throws {
-        let web3 = try! await Web3.new(LocalTestCase.url)
-        let contract = web3.contract(EthereumContractTest.overloadedFunctionsABI,
-                                        at: EthereumAddress("0x6394b37Cf80A7358b38068f0CA4760ad49983a1B")!)!
-        let parameters: [AnyObject] = [Data.randomBytes(length: 32)!, Data.randomBytes(length: 32)!] as [AnyObject]
+        let web3 = try await Web3.new(LocalTestCase.url)
+        let contract = try XCTUnwrap(web3.contract(EthereumContractTest.overloadedFunctionsABI, at: EthereumAddress("0x6394b37Cf80A7358b38068f0CA4760ad49983a1B")))
+        let parameters: [AnyObject] = [Data.randomBytes(length: 32), Data.randomBytes(length: 32)] as [AnyObject]
         let functionSignature = getFuncSignature("setData(bytes32,bytes)")
         let transaction = contract.createWriteOperation(functionSignature, parameters: parameters)
         XCTAssertNotNil(transaction)
 
-        let decodedData = contract.contract.methods[functionSignature]?.first?.decodeInputData(transaction!.transaction.data)
+        let data = try XCTUnwrap(transaction?.transaction.data)
+        let decodedData = try XCTUnwrap(contract.contract.methods[functionSignature]?.first?.decodeInputData(data))
         XCTAssertNotNil(decodedData)
-        XCTAssertEqual(decodedData!["0"] as! Data, parameters[0] as! Data)
-        XCTAssertEqual(decodedData!["1"] as! Data, parameters[1] as! Data)
+        XCTAssertEqual(try XCTUnwrap(decodedData["0"] as? Data), try XCTUnwrap(parameters[0] as? Data))
+        XCTAssertEqual(try XCTUnwrap(decodedData["1"] as? Data), try XCTUnwrap(parameters[1] as? Data))
     }
 }