Jimmy Koppel is the founder of Mirdin — the software-design teaching company behind the Advanced Software Design Course — and an MIT-trained programming-language theorist whose course material is unusually rigorous about the theoretical underpinnings of software-design decisions: type theory, algebraic data structures, and the lambda-calculus foundations underneath modern languages.
His CourseFlix listing carries the Advanced Software Design Course by Mirdin — a treatment of software design that approaches the discipline at a much deeper level than framework-or-pattern tutorials.
Material is paid and aimed at experienced software engineers ready to study software design from a theoretical-foundations angle. For broader content, see CourseFlix's System Design & Architecture category page.