Marvellex presents itself as a blockchain ecosystem aiming to make value creation and exchange “secure, efficient, and economical,” positioning blockchain as the backbone of digital economies and tackling adoption issues like volatility and usability. Its public site highlights community programs, listings news, and an all-in-one “digital family” experience. DeFi Portfolio & NFT Dashboard (React/Next + Web3) I built a production-ready dApp that lets users connect wallets (MetaMask/WalletConnect), track DeFi positions, and mint/gate NFTs—all in one interface. The app uses Next.js (App Router) + TypeScript with SSR/ISR for fast, SEO-friendly pages, and Wagmi + viem/Ethers for secure contract reads/writes (ERC-20/721/1155). Users can view real-time balances, yields, and PnL via on-chain calls and The Graph/GraphQL indexing, with charts and alerts for price and gas changes. NFT creators get an admin panel for allowlists, signature-based claims (SIWE), and role-based content gating. I designed a reusable component system with Tailwind + shadcn/ui, enforced a11y, and added end-to-end tests (Jest/Playwright) and CI/CD (GitHub Actions → Vercel). The codebase follows feature-based architecture, typed APIs, and rigorous error handling/analytics for reliability. Outcome: sub-1s perceived loads, >95 Lighthouse scores, and a measurable lift in activation and repeat usage.