David Lumen is an accomplished iOS Developer with extensive experience in Retail, Banking, and E-commerce industries, having worked for top big tech companies. Lumen is highly skilled in iOS SDK, Swift, Objective-C, debugging, ARC, Unit-Testing, and GCD. He has a Postgraduate Degree in Computer Science from Bauman Moscow State Technical University and a Bachelor's degree in Marketing/Marketing Management, General from Russian State Agrarian University. As a public speaker, contributor, and T-shape advocate, Lumen is highly admired in the tech community. He currently holds the Senior iOS Developer position at OZON.ru and has previously worked as a Senior iOS Developer at Sberbank, iOS Developer at King Bird Studio, and Software Engineer Intern at Paragon Software. Lumen is approachable and openly invites inquiries from peers and recruiters.