Alpaca

Alpaca is an API-first brokerage platform designed for developers and algorithmic traders. It offers commission-free trading for stocks and ETFs, providing the infrastructure for live trading and custom AI integration. Users can build their own trading bots and integrate with various tools. The platform includes an AI-powered natural language trading feature via Alpaca's MCP Server. While it provides robust API access, users typically build components like backtesting engines or cloud IDEs themselves, often using Python libraries or third-party tools.