She graduated with a bachelor's degree in Industrial Engineering from University of Puerto Rico at Mayagüez.
After graduation, Alvarez visited a friend in Texas, where she discovered the Deep Ellum music scene in Dallas. She became active in the local club scene and signed a record deal with Brando Records. She recorded her debut album Ruleta in Spanish with producer Javier Willis. She wrote and performed all the songs on the album. A few months later, Kevin Lawrie at Sony Norte heard the tracks and signed her to the Miami-based label. Alvarez continued to work in the Latin music scene, getting airplay for her debut single "Hoy" on stations throughout Puerto Rico and the US. Picky Talarico directed the video for "Hoy", which was shot on location in Buenos Aires, Argentina. The program director for Entravision Communications "Super Estrella" network happened upon her while she was performing at the Grove in Los Angeles. The following week "Hoy" was added to the playlist for all of the "Super Estrella" network across the US. This led Sony Norte to release a second single "Cada Momento". The video was directed by Nory Niven.
While touring and performing in Texas, Alvarez became close friends with her Brando Records label mates Blue October, who invited her to sing on two songs: "Come in Closer" off of their album History for Sale and "Into the Ocean" from their platinum-selling album Foiled.
Alvarez also starred in the independent film "Lycanthrope". The movie features one of her original songs, "This Is Love", which can be found on the re-release of her album "Ruleta".
Alvarez landed a spot on the CBS TV show Rockstar: Supernova in 2006. Her outrageous costumes and creative spin on the songs she performed were both praised and derided by the media. Los Angeles Times pop music critic Ann Powers stated that "Rockstar's most intriguing contestant, the Puerto Rican punk chanteuse Zayra Alvarez" while her hometown paper, the Dallas Observer, referred to her "serious, possibly fatal, pitch deficiency". During her tenure, she covered many well-known songs, including "Call Me", "867-5309/Jenny", and "Everybody Hurts". On week 7, Alvarez took a huge risk by singing her own original song, ""Lluvia de Mar,"" in Spanish on Prime Time TV, and while Supernova (Tommy Lee, Gilby Clarke and Jason Newstead) could not help but like it they still wanted her to sing a more traditional rock song. She was eliminated from the show on August 16. Shortly after her departure from Rockstar:Supernova, the Los Angeles Times ran a feature article on her. In it, the writer Josh Kun stated, "Zayra Alvarez, an aspiring arena goddess born and raised in Puerto Rico, makes it deep into the prime-time CBS-TV competition of "Rock Star: Supernova." She prances around ... in peekaboo cosmic blue cat suits like she's Ziggy Stardust's long lost Caribbean cousin."
After the show Alvarez returned to Texas and moved to Austin. She decided it was time for her to record her songs in English in a style that took her far beyond traditional Latin music. She also dropped her last name and became known simply as Zayra. Her latest album, Baby Likes To Bang, was released on September 14, 2010 by Brando Records. This album represents Zayra's transition into dance music, featuring remixes by top DJs from around the world. Two singles have been released from the album, "V.I.P." and "Baby Likes To Bang."
"V.I.P.", the first single from the album and a Top 5 Billboard Dance Club Hit, was remixed by Dave Audé, Mike Rizzo, DJ Paulo & Alain Jackinsky, Steph Seroussi, and Adrian Benavides. After the release of the single, the blogger Arjan wrote "every summer needs a dance queen and Zayra is turning out to be this season's club royalty."
The second single "Baby Likes To Bang" was released November 8, 2010. It was declared the #1 Dance Breakout by Billboard and was the #3 most added song by DJ's behind Katy Perry and Rihanna. The single features remixes from DJ Escape & Tony Coluccio, Razor N Guido, Mixin Marc & Tony Svejda and Steph Seroussi & Nam. The music videos for "Baby Likes to Bang" and "V.I.P." were composed by Merritt Fields of Rainmaker Artists.
Zayra has been performing around the country in support of the record, including Austin Fashion Week, Atlanta Pride 2010, TigerHeat, and multiple performances in Los Angeles and New York.