Leon Bolier (Dutch pronunciation: ; born Leendert Wouter Bolier on October 21, 1980) is a Dutch classically trained trance composer, DJ, and record producer. His career began to flourish in 2008 with a number of successful song releases including the hit song "Ocean Drive Boulevard". He placed #95 on the DJMag's 2008 list of the top 100 DJ's in the world, and moved up 32 places in 2009, and rests at #68 in 2010. He has had his songs played by top DJs like Tiësto and Armin van Buuren as well as his tracks appearing on famous trance compilations such as In Search of Sunrise 4: Latin America and A State of Trance 2006. Two of his albums were released during the span of 2008 and 2010, called Pictures and Phantasma, respectively. By the following year, which coincided with his complete dropping out of the DJMag's list of the top 100 DJ's, the first signs of his change of heart in the musical style began to flourish, which had become more apparent over the course of time since and transformed into the new representative standard of his current works, as depicted in "Disco Davai" among such, which bear no resemblance to what he originally was recognized for.

At the end of 2014, Leon started working on his third album under his new alias WSTLNDR. The 12-track work, called Atmostopia, features his complete return to his original creative roots which were not seen in his repertoire since the release of Phantasma. The album was released on Black Hole on September 14, 2015.