[1][2][3] Rivera performed extensively at New York City Opera early in her career, performing such roles as Hansel Hansel and Gretel (2002), Lazuli in Chabrier's L'étoile (2002), Meg in Mark Adamo's Little Women (2003), Cherubino in The Marriage of Figaro (2004), Rosina in The Barber of Seville (2005), Myrrhine in Adamo's Lysistrata (2006), and Nerone in Handel's Agrippina (2007).
[15][16] In 2013 Rivera performed Kurt Weill’s Mahagonny Songspiel and portrayed the Nanny in Ernst Toch’s Princess and the Pea at the Gotham Chamber Opera.
[23] In 2011 she performed the role of Nerone on a recording of Handel's Agrippina with the Akademie für Alte Musik Berlin under conductor René Jacobs for Harmonia Mundi.
Rivera was a regular contributor to The Huffington Post Arts and Culture Section and, in 2015, was named the Center for Contemporary Opera's first Director for Artistic Development.
[1] An internal review found that these problems arose not as a result of diversity and inclusion lapses but because of bad management, which Rivera took responsibility for.