An XR Developer designs and develops immersive applications using augmented reality (AR), virtual reality (VR), and mixed reality (MR) technologies. They work with game engines like Unity or Unreal Engine, programming languages like C# or C++, and hardware such as VR headsets or AR glasses. Their role includes creating interactive experiences, optimizing performance, and integrating 3D assets. XR Developers are commonly employed in gaming, training simulations, healthcare, and other industries exploring immersive technology.