śruti smṛti

In this verse, there is a statement of fact: Sri Sankara is srutismrtipurananam alayam. A shrine, a temple, is called alaya. Also any place where a sacred thing is kept is an alaya. Books are sacred, so a library is called pustakalaya. Sri Sankaracarya is an alaya of sruti-smrti-puranas. Sruti is all the Vedas, the karmakanda as well as the last portion of the Vedas known as Vedanta. Since sruti has come down to us through the rishis, there is no authorship (apaurusheyatvam), whereas, smrti has authorship. The kalpa-sutras are a development of the statements of the smrti, written by people who had a status similar to the one the rishis enjoyed. They knew about rituals, values, dharma, etc.