Question: Sirappuli Nayanar is described to have served the devotees of a Hindu god who is the Supreme Being within what tradition?
Context: Sirappuli Nayanar, also known as Sirappuli (also spelled as Cirappuli, Chirappuli), Sirapuli Nayanar, Sirappuliyar (Chirappuliyar), was a Nayanar saint, venerated in the Hindu sect of Shaivism.  He is generally counted as the thirty-fifth in the list of 63 Nayanars.  Sirappuli Nayanar is described to have served the devotees of the god Shiva and worshipped the god with various ritual practices. Muruga Nayanar or Muruka Nayanar is the 15th Nayanar saint.  Traditional hagiographies like "Periya Puranam" (13th century CE) and "Thiruthondar Thogai" (10th century CE) describe him as a great devotee of the Hindu god Shiva.  He is described to have lived an ascetic life, filled with austerity and selfless devotion to Shiva, spending his time in collecting flowers from woodlands and decorating the Shiva Lingam with garlands and coronets. Satti Nayanar (Shatti Nayanar, Chaththi Nayanar), also known as Satti (Sathi), Sathiyar, Shakti Nayanar, Shakti, Shaktiyar (Saktiyar), Sattiyandar and Thiru-Saththi Nayanar, is a Nayanar saint, venerated in the Hindu sect of Shaivism.  He is generally counted as the forty-fifth in the list of 63 Nayanars.  Satti Nayanar is described to cut off the tongue of whoever talked ill of his patron god Shiva or Shiva's devotees. Viralminda Nayanar, also known as Viranmindar (Viranmintar), Viranmintan and Viranminda Nayanar (Viranminta Nayanar), is a Nayanar saint, venerated in the Hindu sect of Shaivism.  He is generally counted as the sixth in the list of 63 Nayanars.  He was a contemporary of Sundarar (8th-9th century CE).  It is sometimes described as the only Nayanar from Kerala.  Viralminda Nayanar is described in legends as the reason Sundarar composed to a hymn to the Nayanar saints, which became the first compilation of the list. Nesa Nayanar (Tamil: நேச நாயனார் ), also known as Sivanesa Nayanar, Neca Nayanar (Necha nayanar), Nesanar, Nesar and Nesan (Necan), was a Nayanar saint, venerated in the Hindu sect of Shaivism.  He is generally counted as the fifty-ninth in the list of 63 Nayanars.  Nesa Nayanar is described to be a weaver, who was always engrossed in remembering his patron god Shiva and gifting clothes he knit to devotees of the deity. Rudra Pasupathi Nayanar is the 16th Nayanar saint.  Traditional hagiographies like "Periya Puranam" (13th century CE) and "Thiruthondar Thogai" (10th century CE) detail his legendary life and services to the Hindu god Shiva.  Pasupathi Nayanar was a learned Brahmin devotee who practised chanting of the Shri Rudram Chamakam, a Vedic hymn dedicated to Rudra (a form of Shiva).  Therefore, he is known by the name Rudra Pasupathi Nayanar. Shiva ( ; Sanskrit: शिव, IAST: Śiva, lit.  "the auspicious one") is one of the principal deities of Hinduism.  He is the Supreme Being within Shaivism, one of the major traditions within contemporary Hinduism. Kari Nayanar is the 47th Nayanar saint.  Traditional hagiographies like "Periya Puranam" (13th century CE) and "Thiruthondar Thogai" (10th century CE) detail his legendary life and services to the Hindu god Shiva.  Kari Nayanar was a vedic Brahmin devotee as well as a Tamil poet with an understanding of Sanskrit.  The poet-saint compiled the vedic truths in "Kovai"(Anthology), a Tamil composition titled "Karikkovai".  Therefore the saint got the name as Kari Nayanar. Arivattaya Nayanar or Thayanar (Tamil: அரிவட்டாய நாயனார்) was the 12th Nayanar, a group of 63 Shaivite saints, venerated as great devotees of the Hindu god Shiva.  Nayanars lived before or during the lifetime of Sundaramurthy Nayanar (8th Century). Manakanchara Nayanar, also known as Manakkanychaara Nayanar, Manakkancharar, Manakanjara Nayanar, Mankkanjara Nayanar and Manakkanjarar, was a Nayanar saint, venerated in the Hindu sect of Shaivism.  He is generally counted as the twelfth in the list of 63 Nayanars.  Like other Nayanars, he was a fervent devotee of the god Shiva.  Manakanchara Nayanar is dated to the 8th century and was a contemporary of Eyarkon Kalikkama Nayanar, a Nayanar saint and his son-in-law as well as Sundarar.  He is described to have cut his daughter's hair and given it to Shiva disguised as a Shaiva ascetic, on her wedding day.
Answer: Shaivism