I need a production-ready, online hot wallet that lets end-users store, send, and receive multiple cryptocurrencies from a single, intuitive interface. The build must cover both the user-facing application and the back-end services that interact with the relevant blockchain networks. Key requirements • Support for at least Bitcoin, Ethereum, and any additional major coins you can integrate without licensing hurdles. • Secure key management: encrypted private keys on the server side, optional 2FA before any outbound transfer, and clear separation between hot funds and fee wallets. • Standard wallet functions: address generation, QR code display, balance fetch, transaction history with on-chain links, and adjustable fee selection. • Real-time blockchain monitoring so deposits appear as pending instantly and confirm automatically. • Clean, responsive UI that can be embedded later into mobile apps. • REST or WebSocket API endpoints documented for future third-party integrations. • Deployment scripts (Docker or similar) plus a concise tech manual that allows my team to reproduce the environment from scratch. Acceptance criteria 1. I can spin up the stack on a fresh VPS, create a user account, and carry out a BTC and ETH round-trip (deposit → confirmation → withdrawal) without manual node intervention. 2. All secrets remain encrypted at rest and never leave the server unencrypted. 3. Code passes a brief security review for common web vulnerabilities (SQLi, XSS, CSRF, etc.). 4. Full source code, database schema, and configuration files are delivered in a private repository. Indicate the frameworks, libraries, or SDKs you propose—whether that’s Node.js with Express, Django, Go, Rust, or another stack you’re experienced with—and provide a rough time frame for each milestone so I can align our internal schedule.