Gst applicability for working remotely

I am a freelance software developer located in Haryana. I am working remotely through a company based out of Maharashtra for a US based client. I work directly with the US client on a day to day basis but get monthly payments against invoices, from the Indian company. My gross annual receipts would be less than 20L.

Is it mandatory for me to register with GST because of "Businesses involving inter-state supply of goods and services" clause or since I am working remotely I may be exempted?