Mark Johnson is a seasoned iOS engineer with over a decade of experience building and modernizing mobile products, currently contributing to iOS Foundation at Square. His career spans startups and established companies—leading mobile teams at Supersapiens, rebuilding clients in Swift at Proscape, and shipping iOS features at Block.one and Doximity—demonstrating deep expertise in Swift, Objective-C, encryption, sync, and media rendering. He has a strong background in systems-level engineering from earlier C/C++ and .NET roles, which informs pragmatic, performance-minded mobile architecture decisions. Known for taking sole ownership of substantial rewrites and mission-critical features, he blends hands-on implementation with cross-functional leadership. Based in Blacksburg, Virginia, he brings a long arc of product-focused engineering that pairs legacy-system fluency with modern iOS best practices.
Find and Hire Top DevelopersWe’ve analyzed the programming source code of over 60 million software developers on GitHub and scored them by 50,000 skills. Sign-up on Prog,AI to search for software developers.