Ryan Koepke is a Canadian guitarist, composer, multi-instrumentalist, and producer from Kelowna, British Columbia, best known as the creative force behind the progressive metal project Cepheidae Variable. With more than 15 years of experience as a musician and producer, Koepke independently writes, performs, mixes, and produces his music. His work blends technical, riff-driven composition with melodic leads, odd time signatures, orchestral textures, and evocative soundscapes that convey narrative and emotion.

Cepheidae Variable’s debut album Primordial Reverie (released November 7, 2025) is a fully instrumental, three-act concept record that guides listeners from symphonic fantasy landscapes into intricate, sci-fi-inspired progressive metal, with recurring motifs and evolving themes crafted to reward repeat listens. Critics have praised the project’s emotional depth and compositional ambition; Prog Magazine called it “genuinely exciting,” while Rock Hard Italy highlighted its “harmony of sounds and atmosphere… a blend of technique and inspiration pushed to high qualitative levels.”

Beyond his work with Cepheidae Variable, Koepke also offers professional production services, including mixing, mastering, and session work, helping other artists realize their creative visions. He continues to push the boundaries of storytelling in metal and progressive music, with upcoming releases that aim to further evolve his sound and artistic identity.