We are seeking a Senior UX Interface Designer with a genuine, discerning visual sensibility who can recognize the difference between a screen that merely functions and one that commands attention, builds trust, and makes an athlete want to keep coming back. This is not a role for someone who executes a design system without aesthetic judgment. We need a designer who has a point of view, can defend it, and can elevate our product visually while remaining disciplined within our design constraints. This role owns the Presentation Layer — how the product is formatted in terms of fonts, graphics, and animation, along with intuitive navigation. Key focus areas include innate visual design sensibility applied to a premium dark-surface consumer product; identity-driven, personalized experiences that adapt to each user's performance profile; high-quality motion and interaction design that communicates performance and progress; and action-oriented workflows that eliminate passive data consumption. This is a startup environment where the ideal candidate thrives building from 0->1, is comfortable with ambiguity, and takes ownership rather than waiting for direction. We move fast, hold a high visual standard, and ship against hard dates. We also leverage modern AI-assisted development tools to accelerate delivery; comfort in these environments is a must.