I’m building a secure, full-featured e-commerce solution that runs smoothly on iOS, Android, and the Web. The core stack can lean on Python for the API layer, with Java or C++ wherever high-performance modules make sense, but I’m open to a workflow you can justify that keeps code clean, well-documented, and easy to maintain. Core scope The first release must cover user account management (registration, login, password reset, profile editing) and end-to-end payment processing with major gateways. A responsive storefront, basic product catalogue, and an admin dashboard will round out the MVP. UX consistency across mobile and web is essential, and I’d like to see thoughtful error handling, secure data storage, and unit tests from day one. Deliverables for this milestone • iOS app build (ready for TestFlight) • Android app build (ready for internal track) • Web front-end deployed to a staging URL • REST or GraphQL API with documentation • Payment gateway integration (sandbox keys) • Brief setup guide and code walkthrough video Acceptance criteria 1. A new user can register, browse sample products, add one to cart, and complete a sandbox payment on all three platforms. 2. Source code passes automated tests and static analysis. 3. Deployment instructions reproduce the environment on a fresh machine in under 30 minutes. 4.Expert Coder Timelines are flexible enough to let you do things properly but tight enough to keep momentum; suggest a realistic schedule in your proposal along with any preferred frameworks or libraries.