Who is upper caste Nair or Vishwakarma?

Nairs are a branch of Nagavanshi Kshatriyas found in the Indian state of kerala. They are similar to the Bands , Nagavanshi Rajputs and Jats. Vishwakarmas are supposed to be engaged in the construction jobs . But, they fall under the Brahmin caste. Regarding who is upper , the Brahmins or the Kshatriyas is tricky question . According to the indian constitution no one is upper or lower , all are equal before law and of course same in the eyes of God !