diff --git a/Sources/SwaggerSwiftCore/API Request Factory/Models/APIRequest+Swiftable.swift b/Sources/SwaggerSwiftCore/API Request Factory/Models/APIRequest+Swiftable.swift
index 5f5d102..82eb142 100644
--- a/Sources/SwaggerSwiftCore/API Request Factory/Models/APIRequest+Swiftable.swift	
+++ b/Sources/SwaggerSwiftCore/API Request Factory/Models/APIRequest+Swiftable.swift	
@@ -19,10 +19,6 @@ extension APIRequest {
         }.joined(separator: ", ")
     }
 
-    private var functionReturnType: String {
-        returnType.typeName.toString(required: true)
-    }
-
     private func makeRequestFunction(serviceName: String?, swaggerFile: SwaggerFile) -> String {
         let servicePath = self.servicePath.split(separator: "/")
             .map {
@@ -155,11 +151,11 @@ if let \(($0.swiftyName)) = \(headersName).\($0.swiftyName) {
             .addNewlinesIfNonEmpty()
 
         let responseTypes = self.responseTypes
-            .map { $0.print(apiName: serviceName ?? "") }
+            .map { $0.print(apiName: serviceName ?? "", errorType: returnType.failureType.toString(required: true)) }
             .joined(separator: "\n")
 
         return """
-private func _\(functionName)(\(functionArguments)) async -> \(functionReturnType) {
+private func _\(functionName)(\(functionArguments)) async throws(\(returnType.failureType.toString(required: true))) -> \(returnType.successType.toString(required: true)) {
     let endpointUrl = baseUrlProvider().appendingPathComponent("\(servicePath)")
 
     \(queries.count > 0 ? "var" : "let") urlComponents = URLComponents(url: endpointUrl, resolvingAgainstBaseURL: true)!
@@ -175,20 +171,24 @@ private func _\(functionName)(\(functionArguments)) async -> \(functionReturnTyp
     do {
         (data, response) = try await urlSession().\(urlSessionMethodName)
     } catch {
-        return .failure(.requestFailed(error: error))
+        throw .requestFailed(error: error)
     }
 
     if let interceptor {
         do {
-            try await interceptor.networkDidPerformRequest(urlRequest: request, urlResponse: response, data: data, error: nil)
+            try await interceptor.networkDidPerformRequest(
+                urlRequest: request,
+                urlResponse: response,
+                data: data,
+                error: nil
+            )
         } catch {
-            return .failure(.requestFailed(error: error))
+            throw .requestFailed(error: error)
         }
     }
 
     guard let httpResponse = response as? HTTPURLResponse else {
-        let error = NSError(domain: "\(serviceName ?? "Generic")", code: 0, userInfo: [NSLocalizedDescriptionKey: "Returned response object wasnt a HTTP URL Response as expected, but was instead a \\(String(describing: response))"])
-        return .failure(.requestFailed(error: error))
+    fatalError("The response must be a URL response")
     }
 
     let decoder = JSONDecoder()
@@ -199,7 +199,7 @@ private func _\(functionName)(\(functionArguments)) async -> \(functionReturnTyp
     default:
         let result = String(data: data, encoding: .utf8) ?? ""
         let error = NSError(domain: "\(serviceName ?? "Generic")", code: httpResponse.statusCode, userInfo: [NSLocalizedDescriptionKey: result])
-        return .failure(.requestFailed(error: error))
+        throw .requestFailed(error: error)
     }
 }
 
@@ -238,10 +238,31 @@ private func _\(functionName)(\(functionArguments)) async -> \(functionReturnTyp
         body += "\n"
 
         body += """
-        \(accessControl) func \(functionName)(\(functionArguments)\(functionArguments.isEmpty ? "" : ", ")completion: @Sendable @escaping (\(functionReturnType)) -> Void = { _ in }) {
+        \(accessControl) func \(functionName)(\(functionArguments)\(functionArguments.isEmpty ? "" : ", ")completion: @Sendable @escaping (Result<\(returnType.successType.toString(required: true)), \(returnType.failureType.toString(required: true))>) -> Void = { _ in }) {
             _Concurrency.Task {
-                let result = await _\(functionName)(\(parameters.map { "\($0.name.variableNameFormatted): \($0.name.variableNameFormatted)" }.joined(separator: ", ")))
-                completion(result)
+                do {
+
+"""
+
+        if returnType.successType.toString(required: true) == "Void" {
+            body += """
+                    try await _\(functionName)(\(parameters.map { "\($0.name.variableNameFormatted): \($0.name.variableNameFormatted)" }.joined(separator: ", ")))
+                    completion(.success(()))
+
+        """
+        } else {
+            body += """
+                    let result = try await _\(functionName)(\(parameters.map { "\($0.name.variableNameFormatted): \($0.name.variableNameFormatted)" }.joined(separator: ", ")))
+                    completion(.success(result))
+
+        """
+        }
+
+        body += """
+                } catch let error {
+                    let error = error as! \(returnType.failureType.toString(required: true)) 
+                    completion(.failure(error))
+                }
             }
         }
 
@@ -256,11 +277,14 @@ private func _\(functionName)(\(functionArguments)) async -> \(functionReturnTyp
 
         body += "\n"
 
+        if returnType.successType.toString(required: true) != "Void" {
+            body += "@discardableResult\n"
+        }
+
         body +=
         """
-        @discardableResult
-        \(accessControl) func \(functionName)(\(functionArguments)) async -> \(functionReturnType) {
-            await _\(functionName)(\(parameters.map { "\($0.name.variableNameFormatted): \($0.name.variableNameFormatted)" }.joined(separator: ", ")))
+        \(accessControl) func \(functionName)(\(functionArguments)) async throws(\(returnType.failureType.toString(required: true))) -> \(returnType.successType.toString(required: true)) {
+            try await _\(functionName)(\(parameters.map { "\($0.name.variableNameFormatted): \($0.name.variableNameFormatted)" }.joined(separator: ", ")))
         }
 
         """
diff --git a/Sources/SwaggerSwiftCore/API Request Factory/Models/APIRequestResponseType.swift b/Sources/SwaggerSwiftCore/API Request Factory/Models/APIRequestResponseType.swift
index 33a1a60..e154ec9 100644
--- a/Sources/SwaggerSwiftCore/API Request Factory/Models/APIRequestResponseType.swift	
+++ b/Sources/SwaggerSwiftCore/API Request Factory/Models/APIRequestResponseType.swift	
@@ -36,17 +36,16 @@ enum APIRequestResponseType {
         }
     }
 
-    func print(apiName: String) -> String {
+    func print(apiName: String, errorType: String) -> String {
         let failed = !statusCode.isSuccess
-        let swiftResult = failed ? "failure" : "success"
 
         let resultType: (String, Bool) -> String = { resultType, enumBased -> String in
             let resultBlock = resultType.count == 0 ? "" : "(\(resultType))"
             if failed {
                 if enumBased {
-                    return ".backendError(error: .\(statusCode.name)\(resultBlock))"
+                    return "\(errorType).backendError(error: .\(statusCode.name)\(resultBlock))"
                 } else {
-                    return ".backendError(error: \(resultType))"
+                    return "\(errorType).backendError(error: \(resultType))"
                 }
             } else {
                 return enumBased ? ".\(statusCode.name)\(resultBlock)" : resultType
@@ -58,27 +57,28 @@ enum APIRequestResponseType {
             return """
 case \(statusCode.rawValue):
     let result = String(data: data, encoding: .utf8) ?? ""
-    return .\(swiftResult)(\(resultType("result", resultIsEnum)))
+    \(failed ? "throw" : "return") \(resultType("result", resultIsEnum))
 """
         case .object(let statusCode, let resultIsEnum, let responseType):
             if responseType == "Data" {
                 return """
     case \(statusCode.rawValue):
-        return .\(swiftResult)(data)
+        \(failed ? "throw" : "return") data
     """
             } else {
                 return """
 case \(statusCode.rawValue):
     do {
         let result = try decoder.decode(\(responseType.modelNamed).self, from: data)
-
-        return .\(swiftResult)(\(resultType("result", resultIsEnum)))
+        \(failed ? "throw" : "return") \(resultType("result", resultIsEnum))
     } catch let error {
-        interceptor?.networkFailedToParseObject(urlRequest: request,
-                                                urlResponse: response,
-                                                data: data,
-                                                error: error)
-        return .failure(.requestFailed(error: error))
+        interceptor?.networkFailedToParseObject(
+            urlRequest: request,
+            urlResponse: response,
+            data: data,
+            error: error
+        )
+        throw \(errorType).requestFailed(error: error)
     }
 """
             }
@@ -86,12 +86,12 @@ case \(statusCode.rawValue):
             if resultIsEnum {
                 return """
 case \(statusCode.rawValue):
-    return .\(swiftResult)(\(resultType("", resultIsEnum)))
+    \(failed ? "throw" : "return") \(resultType("", resultIsEnum))
 """
             } else {
                 return """
 case \(statusCode.rawValue):
-    return .\(swiftResult)(\(resultType("()", resultIsEnum)))
+    \(failed ? "throw" : "return") \(resultType("()", resultIsEnum))
 """
             }
         case .int(let statusCode, _):
@@ -107,14 +107,14 @@ case \(statusCode.rawValue):
                             ]
         )
 
-        return .failure(.requestFailed(error: error))
+        throw \(errorType).requestFailed(error: error)
     }
 """
         case .double(let statusCode, _):
             return """
 case \(statusCode.rawValue):
     if let stringValue = String(data: data, encoding: .utf8), let value = Double(stringValue) {
-        return .success(value)
+        return value
     } else {
         let error = NSError(domain: "\(apiName)",
                             code: 0,
@@ -123,14 +123,14 @@ case \(statusCode.rawValue):
                             ]
         )
 
-        return .failure(.requestFailed(error: error))
+        throw \(errorType).requestFailed(error: error)
     }
 """
         case .float(let statusCode, _):
             return """
 case \(statusCode.rawValue):
     if let stringValue = String(data: data, encoding: .utf8), let value = Float(stringValue) {
-        return .success(value)
+        return value
     } else {
         let error = NSError(domain: "\(apiName)",
                             code: 0,
@@ -139,14 +139,14 @@ case \(statusCode.rawValue):
                             ]
         )
 
-        return .failure(.requestFailed(error: error))
+        throw \(errorType).requestFailed(error: error)
     }
 """
         case .boolean(let statusCode, _):
             return """
 case \(statusCode.rawValue):
     if let stringValue = String(data: data, encoding: .utf8), let value = Bool(stringValue) {
-        return .success(value)
+        return value
     } else {
         let error = NSError(domain: "\(apiName)",
                             code: 0,
@@ -155,14 +155,14 @@ case \(statusCode.rawValue):
                             ]
         )
 
-        return .failure(.requestFailed(error: error))
+        throw \(errorType).requestFailed(error: error)
     }
 """
         case .int64(let statusCode, _):
             return """
 case \(statusCode.rawValue):
     if let stringValue = String(data: data, encoding: .utf8), let value = Int64(stringValue) {
-        return .success(value)
+        return value
     } else {
         let error = NSError(domain: "\(apiName)",
                             code: 0,
@@ -171,7 +171,7 @@ case \(statusCode.rawValue):
                             ]
         )
 
-        return .failure(.requestFailed(error: error))
+        throw \(errorType).requestFailed(error: error)
     }
 """
         case .array(let statusCode, let resultIsEnum, let innerType):
@@ -179,10 +179,9 @@ case \(statusCode.rawValue):
 case \(statusCode.rawValue):
     do {
         let result = try decoder.decode([\(innerType)].self, from: data)
-
-        return .\(swiftResult)(\(resultType("result", resultIsEnum)))
+        \(failed ? "throw" : "return") \(resultType("result", resultIsEnum))
     } catch let error {
-        return .failure(.requestFailed(error: error))
+        throw \(errorType).requestFailed(error: error))
     }
 """
         case .enumeration(let statusCode, let resultIsEnum, let responseType):
@@ -197,7 +196,7 @@ case \(statusCode.rawValue):
                         .trimmingCharacters(in: CharacterSet(charactersIn: "\\""))
 
                     let enumValue = \(responseType)(rawValue: cleanedStringValue)
-                    return .\(swiftResult)(\(resultType("enumValue", resultIsEnum)))
+                    \(failed ? "throw" : "return") \(resultType("enumValue", resultIsEnum))
                 } else {
                     let error = NSError(domain: "\(apiName)",
                                         code: 0,
@@ -206,7 +205,7 @@ case \(statusCode.rawValue):
                                         ]
                     )
 
-                    return .failure(.requestFailed(error: error))
+                    throw \(errorType).requestFailed(error: error)
                 }
             """
         }
diff --git a/Sources/SwaggerSwiftCore/API Request Factory/RequestParameterFactory.swift b/Sources/SwaggerSwiftCore/API Request Factory/RequestParameterFactory.swift
index 27e7d96..b4bc9a4 100644
--- a/Sources/SwaggerSwiftCore/API Request Factory/RequestParameterFactory.swift	
+++ b/Sources/SwaggerSwiftCore/API Request Factory/RequestParameterFactory.swift	
@@ -89,7 +89,8 @@ public struct RequestParameterFactory {
 
         let returnType = ReturnType(
             description: "The completion handler of the function returns as soon as the request completes",
-            typeName: .object(typeName: "Result<\(successTypeName), ServiceError<\(failureTypeName)>>")
+            successType: .object(typeName: successTypeName),
+            failureType: .object(typeName: "ServiceError<\(failureTypeName)>")
         )
 
         return (resolvedParameters, resolvedModelDefinitions, returnType)
diff --git a/Sources/SwaggerSwiftCore/Generator/Generator.swift b/Sources/SwaggerSwiftCore/Generator/Generator.swift
index c8bbadb..965e819 100644
--- a/Sources/SwaggerSwiftCore/Generator/Generator.swift
+++ b/Sources/SwaggerSwiftCore/Generator/Generator.swift
@@ -46,34 +46,24 @@ public struct Generator {
 
         typealias APISpec = (APIDefinition, [ModelDefinition])
 
-        let apiSpecs: [APISpec] = try await withThrowingTaskGroup(of: APISpec?.self) { group in
-            var apiSpecs = [APISpec]()
-
-            for service in services {
-                group.addTask {
-                    async let swagger = try await downloadSwagger(
-                        githubToken: githubToken,
-                        organisation: swaggerFile.organisation,
-                        serviceName: service.key,
-                        branch: service.value.branch ?? "master",
-                        swaggerPath: service.value.path ?? swaggerFile.path
-                    )
-
-                    let apiSpec = try await APIFactory(
-                        apiRequestFactory: apiRequestFactory,
-                        modelTypeResolver: modelTypeResolver
-                    ).generate(for: swagger, withSwaggerFile: swaggerFile)
-
-                    return apiSpec
-                }
-            }
+        var apiSpecs = [APISpec]()
 
+        for service in services {
             do {
-                for try await spec in group {
-                    if let spec = spec {
-                        apiSpecs.append(spec)
-                    }
-                }
+                async let swagger = try await downloadSwagger(
+                    githubToken: githubToken,
+                    organisation: swaggerFile.organisation,
+                    serviceName: service.key,
+                    branch: service.value.branch ?? "master",
+                    swaggerPath: service.value.path ?? swaggerFile.path
+                )
+
+                let apiSpec = try await APIFactory(
+                    apiRequestFactory: apiRequestFactory,
+                    modelTypeResolver: modelTypeResolver
+                ).generate(for: swagger, withSwaggerFile: swaggerFile)
+
+                apiSpecs.append(apiSpec)
             } catch {
                 if let error = error as? FetchSwaggerError {
                     error.logError()
@@ -87,11 +77,7 @@ public struct Generator {
                 } else {
                     log("Failed to download Swagger: \(error.localizedDescription)", error: true)
                 }
-
-                throw NSError(domain: "", code: 0)
             }
-
-            return apiSpecs
         }
 
         let destination = URL(fileURLWithPath: swaggerFilePath).deletingLastPathComponent().appendingPathComponent(swaggerFile.destination).path
@@ -216,7 +202,14 @@ public struct Generator {
         return data
     }
 
-    private func downloadSwagger(githubToken: String, organisation: String, serviceName: String, branch: String, swaggerPath: String, urlSession: URLSession = .shared) async throws -> Swagger {
+    private func downloadSwagger(
+        githubToken: String,
+        organisation: String,
+        serviceName: String,
+        branch: String,
+        swaggerPath: String,
+        urlSession: URLSession = .shared
+    ) async throws -> Swagger {
         let data = try await download(
             githubToken: githubToken,
             organisation: organisation,
@@ -369,7 +362,7 @@ public struct Generator {
 extension String {
     func write(toFile path: String, addHeader: Bool = true) throws {
         if addHeader {
-            let file = "// Autogenerated with ❤️ by SwaggerSwift\n// Do not modify this file manually 🙅\n// swiftlint:disable all\n\n" + self.trimmingCharacters(in: CharacterSet.whitespacesAndNewlines) + "\n\n// swiftlint:enable all\n"
+            let file = "// Autogenerated with ❤️ by SwaggerSwift\n// Do not modify this file manually 🙅\n\n" + self.trimmingCharacters(in: CharacterSet.whitespacesAndNewlines) + "\n"
             try file.write(toFile: path, atomically: true, encoding: .utf8)
         } else {
             try self.write(toFile: path, atomically: true, encoding: .utf8)
diff --git a/Sources/SwaggerSwiftCore/Models/ReturnType.swift b/Sources/SwaggerSwiftCore/Models/ReturnType.swift
index 7d31653..0d0c883 100644
--- a/Sources/SwaggerSwiftCore/Models/ReturnType.swift
+++ b/Sources/SwaggerSwiftCore/Models/ReturnType.swift
@@ -2,5 +2,6 @@ import Foundation
 
 struct ReturnType {
     let description: String
-    let typeName: TypeType
+    let successType: TypeType
+    let failureType: TypeType
 }