Connell

Different boundaries in a software system come with different trade-offs to consider. Let's zoom out from functions to distributed systems and look at what encapsulation means at each level.

The original Agile Manifesto lays out 4 simple values:

• Responding to change over following a plan
• Customer collaboration over contract negotiation
• Working software over comprehensive documentation
• Individuals and interactions over processes and tools

Communication over a message bus is often done with Commands and Events. But, what's the difference between them? Aren't they both just messages?

The Transactional Outbox Pattern ensures a message is always published to a message broker when making changes to a database, even if the message broker fails initially. This is essential for event-driven architecture to ensure consistency when other services are rebuilding state from your events.

The communication structures in your organisation influence your software architecture. We explore some examples of this and explain how it relates to Domain-Driven Design (DDD) and Microservices.

We explain the pros and cons of Event Sourcing compared to traditionally updating the current state in a database. We cover trade-offs with Eventual Consistency, problems with concurrency, and options to solve those with optimistic concurrency techniques.

Microservices, a Modular Monolith, or a Big Ball of Mud. This video explains the pros and cons of choosing a distributed system over one big monolith (whether that's a nicely structured Modular Monolith, or just a jumble of spaghetti code).

Bounded Contexts, subdomains and strategic design from Domain-Driven Design explained.

Explaining Aggregate Roots, Domain Events, Entities, Value Objects and Repositories - the building blocks in Domain-Driven Design.

Command-Query Separation and Command-Query Responsibility Segregation. Two design principles explained.

You're probably familiar with the N-tier architecture. This video explains the Hexagonal, Onion and Clean architectures, and how they relate to each other.