Wilayat-e-Ali is Wajib

قال امام صادق علیه السلام : اذا قال احدكم لا اله الا الله محمد رسول الله فلیقل علی امیر المومنین ولی الله.

Imam Jafar Sadiq (as) says: “When any one from you says ‘La ilaha illa Allah, Muhammadan Rasool Allah” then he must say ‘Alian Wali Allah’.

[Ref: Al-Ehtejaaj Vol: 1 Pg: 230 / Bihar Al Anwar Vol: 27 Hadees: 1]