AppWarp Client initialisation is not working

Question

I am trying to initialise AppWarp as follows:

AppWarp::Client::initialize(APPWARP_APP_KEY, APPWARP_SECRET_KEY);

Unfortunately, I am getting the following error:

Undefined symbols for architecture x86_64:
"AppWarp::Client::initialize(std::__1::basic_string, std::__1::allocator >, std::__1::basic_string, std::__1::allocator >, std::__1::basic_string, std::__1::allocator >)", referenced from: AppDelegate::applicationDidFinishLaunching() in AppDelegate.o ld: symbol(s) not found for architecture x86_64 clang: error: linker command failed with exit code 1 (use -v to see invocation)