Metal-cpp doesn't show window content on startup

I'm trying to follow the metal-cpp tutorials I've found at https://developer.apple.com/metal/sample-code/?q=learn

The program seems to be launching correctly (I can see the menu bar and interact with it), but nothing is rendered inside the window. I suppose the culprit is somewhere in the following function (I see it binds the device, the view and the window with the object in charge of drawing stuff in the view)

void core::Application::applicationDidFinishLaunching(NS::Notification *pNotification)
{
    CGRect frame = (CGRect){{100.0, 100.0}, {512.0, 512.0}};
    
    m_Window->init(frame, NS::WindowStyleMaskClosable | NS::WindowStyleMaskTitled, NS::BackingStoreBuffered, false);
    m_Device = MTL::CreateSystemDefaultDevice();
    
    m_View = MTK::View::alloc()->init(frame, m_Device);
    m_View->setColorPixelFormat(MTL::PixelFormat::PixelFormatBGRA8Unorm);
    m_View->setClearColor(MTL::ClearColor::Make(1.0, 0.0, 0.0, 1.0));
    
    m_ViewDelegate = new graphics::ViewDelegate(m_Device);
    m_View->setDelegate(m_ViewDelegate);
    
    m_Window->setContentView(m_View);
    m_Window->setTitle(NS::String::string("Template 1", NS::StringEncoding::UTF8StringEncoding));
    m_Window->makeKeyAndOrderFront(nullptr);
    
    NS::Application* nsApp = reinterpret_cast<NS::Application*>(pNotification->object());
    nsApp->activateIgnoringOtherApps(true);
    
}

but, as you can infer from the fact that I'm failing at the very first tutorial of the bunch, I'm quite lost. I've tried debugging the app with the Xcode debugger and I saw that it never enters in this function.

void ViewDelegate::drawInMTKView(MTK::View *pView)
{
    m_Renderer->Draw(pView);
}

Can it be a symptom of some call missing from my code? Thank you in advance for your help