Design a social media feed system similar to Facebook's news feed that displays personalized content to users based on their interests, connections, and activity. The system should provide a dynamic and engaging user experience, presenting a mix of posts, photos, videos, and other content types from friends, followed pages, and recommended sources. Consider factors such as content ranking algorithms, content freshness, user engagement metrics, and privacy settings in your design. Discuss how you would handle content ingestion, storage, retrieval, and distribution efficiently. Additionally, address scalability, fault tolerance, and caching strategies to handle large volumes of user-generated content and ensure low latency. Provide insights into the technologies, data models, and architectural patterns you would employ to build and deploy this social media feed system effectively.