Quentin Guislain

Led design across every product surface on web and in the app as buycycle became a leading European marketplace for pre-owned cycling equipment, including bikes and components, before expanding into equipment for other sports.

• Product scope. Discovery and purchase across the homepage, shop, product pages and checkout. Account access, user and seller profiles, and listing flows. Chat and negotiation, shipping, packing and claims.
• Product rebrand and design system. Led a complete product rebrand and built, evolved and maintained the design system across web and app.
• Designing in code. Built an AI framework that combined the design system with buycycle’s marketplace model. It let me prototype at production fidelity in Claude Code, using existing components and product rules. In September 2026, I began opening my own merge requests in both repositories.
• Design team. Managed two designers, an intern and a UX writer. Guided designers responsible for core product experiences from problem framing through review and handover.

Built the marketing function and directed global strategy and budgets across all channels and geos. Revenue grew 120% year on year.

Led a team of 10 and the global marketing of a portfolio of 10+ free-to-play games on web and mobile.

Grew user acquisition channels and led App Store Optimisation, lifting the download rate from 22% to 36%.

Designed Facebook apps for 10+ B2C clients, from prototype to project roadmap.

800+ hours across the design process, from user research to prototyping and visual design.