You will also find a variety of traditions that are categorised as "Vidyāpīṭha". The texts of the custom focus on worshipping goddesses generally known as Yoginīs or Ḍākinīs and include antinomian practices dealing with charnel grounds and sexuality. These early historical mentions are in passing and seem like Tantra-like https://youtu.be/1bdBE_QGcvU