Design a brokerage system.

Focus on the core components of a brokerage system, including user account management, trade execution, and transaction processing. Consider how to handle different asset classes (stocks, bonds, options) and the user interface for both retail and institutional clients. Discuss security measures, compliance with regulations, and how to ensure real-time data accuracy. Be prepared to outline the architecture, including backend services, databases, and APIs, while also addressing scalability and performance challenges.