When Vampire Weekend comes back with a new album, it's going to do so without one of its driving creative forces. Rostam Batmanglij announced he's no longer part of the band through his personal Twitter account this afternoon, writing "my identity as a songwriter and producer... needs to stand on its own." "I'm no longer a member of [Vampire Weekend]," wrote Batmanglij, "but... Ezra [Koenig, the band's lead singer and lyricist] and I will continue to collaborate on future projects and future VW songs."

Batmanglij wasn't as prominent a figure in the band as Koenig, but he had just as large an impact on its erudite, gentle sound. In addition to playing a variety of instruments and singing backing vocals, he helped to write some of the band's lyrics and much of its music; he produced the band's self-titled 2008 debut and 2010 followup Contra by himself. (He split production duties on 2013's Modern Vampires of the City with fellow superproducer Ariel Rechtshaid.) Batmanglij sculpted the space around Koenig's hyper-literate missives, and he gave the band's music a serene quality that sounds uniquely his.

Even though Vampire Weekend quickly became one of contemporary rock's most popular and acclaimed bands, Batmanglij worked as a producer, collaborator, and solo artist throughout its ascent. He formed one half of the alt-R&B duo Discovery, wrote and produced for Charli XCX and Carly Rae Jepsen, and worked on soundtracks and plays. His most recent solo single, "EOS," was released about a week ago.

While Batmanglij isn't totally leaving Koenig and his former bandmates behind, his statement suggests he's going to release and work on plenty of non-Vampire Weekend music this year. "There is so much amazing music — all of it dear to me — on its way to you," wrote Batmanglij. "It's an exciting time. And I feel lucky to share it with you." A recent interview with Pitchfork highlights Batmanglij's recent work with PC Music chief A.G. Cook and The Walkmen's Hamilton Leithauser, but it's safe to assume there's more in the pipeline. He talks about Vampire Weekend's next album in the same interview, an album with which he's no longer completely linked; it should be an interesting year for Batmanglij and his old band.