Marco Efraín Masís Fernández (born August 9, 1989), known professionally as Tainy, is a Puerto Rican record producer, songwriter and record engineer. Born and raised in San Juan, Puerto Rico, he entered the world of reggaeton with his work on Mas Flow 2.

Leading a new wave of Latin music for over a decade, Tainy has been the producer of some of the biggest reggaeton hits. A repeated Grammy and BMI Award winner, Tainy has produced for countless artists, including reggaeton pioneers like Daddy Yankee, Wisin & Yandel, Don Omar and others. Recently, he has contributed to global hits like "I Like It" by Cardi B featuring Bad Bunny and J Balvin and "No Es Justo" by Balvin featuring Zion & Lennox.

Tainy produced Oasis with Bad Bunny and Balvin, which dominated global charts and helped Tainy position himself as the number one Latin producer on the Billboard charts for 27 consecutive weeks. Tainy also collaborated with Bad Bunny on the song "Callaíta" which had massive success. He released his global hit "Adicto" alongside Anuel AA and Ozuna which went on to receive multiple Platinum and Gold certification in eight countries and accumulated over 450 million streams and 550 million views on YouTube. Tainy produced the 2019 hit "China" by Anuel AA, Daddy Yankee, and Karol G featuring Ozuna and J Balvin that peaked at number one in 6 countries and reached the top 10 in nine others.

Tainy has produced songs like Lauren Jauregui's debut Latin single "Lento", "Feel It Too" featuring Jessie Reyez and Tory Lanez and Justin Bieber's "Habitual". He released his debut EP titled Neon16 Tape: The Kids That Grew Up on Reggaeton which consists of tracks with several other artists. The single "Nada" featuring Jauregui and C. Tangana was released on February 21, 2020.