Aliyah debuted in WWE as part of Tyler Breeze's entrance at NXT Takeover: Unstoppable on May 20, 2015. She spent her early NXT appearances teaming with fellow babyface Liv Morgan; however, on the August 31, 2016 edition of NXT, Aliyah appeared as the villainous opponent for Liv Morgan, and was on the losing end of their singles contest. She would later make an appearance on SmackDown on January 3, 2017, competing in a losing effort against the villainous Carmella.
After spending most of 2017 as a babyface on the NXT program, Aliyah began turning heel on the October 3 episode of NXT, when she unleashed a more vicious side during her loss to inaugural Mae Young Classic winner Kairi Sane. Aliyah's heel persona continued three weeks later, when she competed in a #1 Contender's Battle Royal, which saw her eliminated by Sage Beckett. She also worked as a villainess on the March 21, 2018 edition of NXT, competing in a losing effort against then-NXT Women's Champion Ember Moon.
After spending months competing as a villainess at house shows (regularly teaming with Reina Gonzalez and Rhea Ripley), Aliyah turned heel on NXT TV on August 15, 2018, when she was shown accepting guidance from villainous NXT Women's Champion Shayna Baszler regarding Aliyah's match against Kairi Sane. Later in the evening, the evil Aliyah unleashed her vicious heel persona during her match, only to ended up submitting to Sane.