While in Calcutta, he stayed with the noted Bengali scholar and social reformer Ishwar Chandra Vidyasagar, who was a friend of Shastri's older brother Nandakumar Nyayachunchu.

[1][2] During the winter 1898–99, he assisted Dr. Cecil Bendall during research in Nepal, collecting information from the private Durbar Library of the Rana Prime Minister Bir Shumsher Jung Bahadur Rana, and the total registration of manuscripts was later published as A Catalogue of Palm-Leaf and selected Paper Manuscripts belonging to the Durbar Library, Nepal (Calcutta 1905) with a historical introduction by Cecil Bendall (including the description of Gopal Raj Vamshavali).

[1] Shastri wrote about this finding in a 1916 paper titled "হাজার বছরের পুরোনো বাংলা ভাষায় রচিত বৌদ্ধ গান ও দোঁহা” (Hajar bochhorer purono Bangla bhasay rochito Bouddho gan o doha) meaning "Buddhist songs and verses written in Bengali a thousand years ago".

[2][7] Shastri was the collector and publisher of many other old works, author of many research articles, a noted historiographer, and recipient of a number of awards and titles.

[1] Some of his notable works were: Balmikir jai, Meghdoot byakshya, Beneyer Meye (The Merchant's Daughter, a novel), Kancanmala (novel), Sachitra Ramayan, Prachin Banglar Gourab, and Bouddha dharma.

[2] His English works include: Magadhan Literature, Sanskrit Culture in Modern India, and Discovery of Living Buddhism in Bengal.