SmartAPI Trading Web App Development

I’m building a full-stack trading platform that taps into Angel One’s SmartAPI for real-time market feeds. The vision is a responsive React front-end paired with a Python back-end that can:

• Stream live equity and derivatives data, cache it efficiently, and keep charts in sync to the second.
• Apply technical analysis on the incoming feed and surface actionable stock and option plays.
• Offer a strategy builder where users write their own Python-based logic—no drag-and-drop blocks or prefabricated templates, just clean custom coding in a browser editor with syntax highlighting and versioning.
• Back-test those strategies against historical data, display key performance metrics, and let users tweak parameters on the fly.
• Switch seamlessly between paper trading and live order placement through SmartAPI, with clear safeguards so real orders never fire by accident.

I already have an Angel One developer account; you’ll get immediate access to the keys once we outline the architecture. Preferred stack is FastAPI (or Django REST) with WebSockets for pushes, PostgreSQL for storage, and React + TypeScript on the client, but I’m open to your suggestions as long as the core remains Python and React.

Acceptance criteria
– Live price stream visible in the UI with <300 ms lag.
– User-written strategy scripts compile, run, and generate signals without server restarts.
– Back-test results show P&L, drawdown, Sharpe, and win rate charts.
– “Trade” button respects the paper/live toggle and logs every transaction.
– Codebase fully containerised and runnable via Docker-compose, with README.

If you’ve previously integrated SmartAPI (or similar broker APIs) and have examples of custom strategy engines, let’s talk timelines and milestones.