Artist Digital Trading Card Marketplace
Developed a marketplace for selling artist digital trading cards.
Challenge
Music fans had limited ways to maintain connections with artists. There was a lack of digital content that fans could "own" beyond live events and merchandise, creating demand for new fan engagement mechanisms.
Solution
Built a mobile-first marketplace for selling artist digital trading cards using Next.js 16 + React 19. Implemented rarity-based CSS effects (hologram, sparkle) and buyer-exclusive content features.
Result
Launched an MVP with near-zero fixed costs and a 3-tier rarity card creation flow.
Team
1 member, 2 months
Design, implementation, operations
Role
Handled product design, admin screens, payment, inventory, and buyer-facing screens.
Led visual/frame dual-layer design, Stripe payment integration, and RLS-based security architecture.
Tech Stack
Key Features
Dual-layer card structure (visual + frame): one visual registered in the admin panel can be expanded into 3 rarity tiers (NORMAL / RARE / SUPER_RARE)
Rarity-specific CSS effects: Hologram and sparkle effects implemented in pure CSS without external libraries
Buyer-exclusive content: Live footage, unreleased tracks, etc. available only to purchasers
Stripe Checkout payments: Secure transactions with webhook signature verification, server-side amount determination, and idempotency guarantees
Atomic inventory management with PostgreSQL FOR UPDATE locks to prevent serial number duplication
Mobile-first UI: 3:4 aspect ratio for real trading card feel, fixed BottomNav, 44x44px touch targets
Technical Highlights
Visual × Frame Separation Design
Separated content (artist images, track names) from design (frame borders, effects), enabling flexible frame additions and seasonal limited cards through code-side management.
Data Protection via RLS
Enabled Row Level Security on all tables, enforcing policies at the DB layer that only purchasers can view exclusive content.
Zero Fixed-Cost Architecture
Achieved near-zero initial fixed costs for MVP operations using Vercel + Supabase Free + Stripe usage-based billing.