Erlend Sogge Heggen, GameDev Series Expert for The Pragmatic Bookshelf, is an open product developer, designing and producing games and web applications as part of an overarching practice of openness. He has participated in long-lasting open source projects as both a hobbyist (jMonkeyEngine) and a professional (Discourse), and currently as an indie entrepreneur (Fish Fight). You can run into Erlend anywhere in the open gamedev community, especially in the realm of Rust.