Full-Stack Developer for a Collectible Card Pack-Opening App

We’re looking for an experienced full-stack developer or small team to build and launch a collectible card pack-opening app. Users will be able to browse and purchase packs, enjoy an animated opening experience, view the physical cards they receive, and choose to keep them in their collection, sell them back, or request shipping. We already have an interactive prototype demonstrating the intended design and user experience. How the platform will work A third-party provider will power the underlying pack-opening engine and operational services, including pack outcomes, card inventory, buyback, and fulfillment, through its APIs. Your responsibility is to deliver the complete, working application around that infrastructure: frontend, application backend, database, user accounts, secure API integrations, payment connectivity, deployment, and testing. This is a full-stack development project, not a frontend-only assignment. The provider supplies the core business infrastructure, but you will own the development and integration of our application from end to end. We will clarify the exact division of responsibilities after reviewing the provider’s API documentation together. Core features * User registration, login, and account management. * Pack catalog with pricing and relevant pack information. * Purchase flow, payment integration, and balance display. * Smooth pack-opening and card-reveal animations. * Personal collection with card details and values. * Sell-back and shipping requests through the provider. * Transaction and pack-opening history. * Basic administration and customer-support tools where not covered by the provider. * Basic analytics and error monitoring. The backend must securely handle API credentials, webhooks, transaction synchronization, and interrupted or failed requests. Purchases, balances, and card ownership must remain consistent, with protection against duplicate charges or openings. Design and scope The initial release will be a responsive web application optimized for mobile, with an app-like experience. We will provide the existing prototype as a design and interaction reference. You may assess whether any existing code is suitable for reuse. The initial scope focuses on the core experience. No tournaments, quests, daily rewards, or other live-ops features are required. What we expect * A deployed, functional application connected to the provider. * Testing of the complete user journey, including payments and failure scenarios. * Source code in our repository, with hosting and service accounts under our ownership. * Clear setup and handover documentation. * Regular progress updates and working demos. * An agreed post-launch bug-fix period. Relevant experience We’re particularly interested in developers who have worked on pack-opening, mystery-box, collectibles, or similar platforms. Strong experience with transactional applications, third-party APIs, payments, and polished mobile interfaces is essential. Please include in your proposal 1. Links to relevant live projects and an explanation of what you personally built. 2. Any previous experience with pack-opening or mystery-box platforms. 3. Your recommended technical approach, including the application backend. 4. Your estimated price and timeline, with assumptions and exclusions. 5. What documentation and access you would need from the third-party provider before confirming the scope. We value relevant experience, clear communication, and a practical delivery plan.