Software Architecture - Metrics and Alarms Monitoring System

In this system-design, we will build a multi-component highly-distributed solution for monitoring, alerting, and dashboarding. These are critical services for maintaining high quality, highly available, fault-tolerant software. This solution will need to operate at a massive scale with potentially billions of requests per day. We will leverage a micro-service architecture to handle the very high volume and high availability requirements. For the metrics, we will separate areas of concern between data-collection, data-ingestion, data-processing, alerting, and dashboarding.

Software Architecture - Payments System

In this system design architecture post we will design a payments system. Payments systems are found across the internet for (1) maintaining a ledger of accounts, balances, and transactions; and (2) the processing of financial transactions between individuals, businesses, and banks. Though simple on the surface to customers, payment systems are complex with many failure scenarios, edge cases, and critical customer and business impact if things go wrong. These systems are critical to each party’s financial interests and their trust in a software platform.

When designing such a complex system where data consistency is of utmost importance we will emphasis designing for (1) data consistency and durability, (2) double-entry accounting (every transaction between two parties is zero-sum), (3) idempotency and exactly-once processing, and (4) immutability.

Software Architecture - Hotel Reservation Booking System

In this article, we will design and implement an online hotel reservation booking system. A similar solution with minor changes could also be used for flight reservations, concerts and events, or reserving unique Airbnb/Vrbo stays. We will start with user requirements and functional edge cases to consider. We will then dig into the backend services and APIs, persistence, transactionality, user and backend flows, the two frontend web applications for users and hotel managers respectively, and conclude with performance and scaling optimizations.

HTTP/3 with QUIC and TLS-1.3

The Internet (IP), Transmission Control (TCP), Hypertext Transfer (HTTP), and Transport Layer Security (TLS and SSL) protocols have long under-pinned the World Wide Web. Each provides a layer of abstraction focusing on specific concerns. Over time enhancements have been made to improve performance, security, and privacy, as well as extend functionality as the web has evolved. HTTP/3 with QUIC generally available in 2019 and TLS-1.3 generally available in 2018 are the latest broadly adopted protocols for web traffic providing enhancements over HTTP/1.1, HTTP/2, and TLS-1.2.

In this article we will dive into the details of HTTP/3 with QUIC and TLS-1.3, including HTTP/2, after first building up to these new technologies layer by layer.