DispatchSemaphore

You can use integrate DispatchSemaphore on execute method.

ExampleService.swift

import VFNetwork
import Foundation

class HomeService: RequestService<HomeAPI> {
    
    let semaphore = DispatchSemaphore(value: 1)

    func getJokes(completion: @escaping (Result<HomeModel, Error>, _ semaphore: DispatchSemaphore) -> Void) {
        execute(.home, responseType: HomeModel.self, semaphore: semaphore, completion: completion)
    }
    
    func getCategories(completion: @escaping (Result<HomeCategories, Error>, _ semaphore: DispatchSemaphore) -> Void) {
        execute(.categories, responseType: HomeCategories.self, semaphore: semaphore, completion: completion)
    }
}

and execute in your viewModel using leave() to terminate group independent execution.

ExampleViewModel.swift

    func getJokes(completion: @escaping (Result<HomeModel, Error>) -> Void) {
        service.getJokes { result, semaphore in
            semaphore.signal()
            switch result {
            case let .success(joke):
                completion(.success(joke))
            case let .failure(error):
                completion(.failure(error))
            }
        }
    }
    
    func getCategories() {
        service.getCategories { result, semaphore in
            semaphore.signal()
            switch result {
            case .success:
                break
            case let .failure(error):
                print(error)
            }
        }
    }

Thats it