I’m building a mobile-first, Web3-enabled logic-puzzle game and now need a backend that can handle both traditional game mechanics and on-chain interactions. Players will solve logic challenges through intuitive touch gestures, earning on-chain rewards and verifiable achievements as they progress. Here’s the flow I have in mind. A player opens the app, signs in with a Web3 wallet, and receives a daily procedurally generated puzzle pulled from the server. When the puzzle is solved, the backend triggers a smart-contract call that mints a non-transferable badge and updates a global leaderboard. All of this must feel instantaneous on mobile networks, so low-latency APIs and efficient data caching are crucial. Core tasks • Design and implement the API that serves puzzle data, records attempts, and manages leaderboards. • Write or integrate a puzzle generator that can produce endless logic puzzles of increasing difficulty. • Build and test the smart-contract layer (Solidity or similar) that handles badge minting and any token logic. • Connect the contract to the backend through Web3.js/Ethers.js so results are committed on-chain only when puzzles are successfully solved. • Set up secure wallet auth (WalletConnect or similar) and user-profile storage. • Provide clear documentation and Postman collections so my front-end team can plug in the mobile UI and touch-gesture controls without friction. Acceptance criteria 1. A user can register or log in with a wallet, request a puzzle, and receive the same puzzle ID across sessions until solved. 2. On correct submission, the contract mints a badge to the user’s wallet and the API returns updated leaderboard data in under 500 ms on a 4G connection. 3. Unit and integration tests cover puzzle validation, API endpoints, and contract functions, with ≥90 % coverage. 4. All code is delivered in a Git repo with a one-command deployment script to a testnet and a cloud host (AWS, GCP, or comparable).