Nick Milo is a US note-taking and personal-knowledge-management educator focused on Obsidian — the popular markdown-based knowledge graph application — as a deliberate thinking and writing tool. He runs Linking Your Thinking (LYT), one of the more influential brands in the personal-knowledge-management space.
His CourseFlix listing carries Obsidian Flight School — a structured introduction to Obsidian as a thinking and writing system, covering the linking patterns, the markdown / plugin ecosystem, and the workflow for building a real second brain rather than just a note dump.
Material is paid and aimed at knowledge workers (including engineers) ready to make note-taking a deliberate productivity tool. For broader content, see CourseFlix's Developer Productivity category page.