Ruurtjan Pul is a software engineer and educator focused on the foundational networking knowledge underneath modern software — particularly DNS as a system that most developers treat as opaque magic.
His CourseFlix listing carries DNS Course for Developers — a structured treatment of how DNS actually works: the resolution flow, the record types, the operational concerns (caching, propagation, the nameserver hierarchy), and the engineering patterns for reasoning about DNS as part of production system design.
Material is paid and aimed at developers ready to fill the DNS-fundamentals gap that most CS curricula skip. For broader content, see CourseFlix's Networking & Protocols category page.
