Projections are one of the core patterns used in Event Sourcing. What we understand by ES is persisting changes that are happening in the application as a sequence of events (also called an event stream). With this context in mind we can define a projection as an answer to a question: what is the current state derived from the event stream?
Read moreConference Talk: How a large corporation used DDD to replace a loyalty system
In this talk Kacper will take you on a journey during which he will reflect on his experience with replacing a complex loyalty system and challenges the project faced. He will share with the audience his thoughts on what worked, what could have been done differently and what caused problems. You will learn how to make best use of Domain Experts and explain why consistency is a business problem. Try to answer if it’s possible to stay sane in the Microservice world and discuss challenges arising when trying to migrate from CRUD persistence to Event Sourcing.
Read moreEvent Sourcing patterns: Replay side effect handling
During the event stream processing sometimes it is desired to perform side effects. The challenge we address in this post is how to perform a replay of an event stream and don't retrigger already performed side effects. It turns out there are a couple of alternatives that can help us solve this problem and the specific solution will depend on needs and the type of event store in use.
Read moreEventStorming Modelling Tips to Facilitate Microservice Design →
Some easy-to-learn techniques to help you get the most out of EventStorming and start designing more domain-aligned software systems!
Team Topologies - Training Report
On 26th of September 2019 I had an opportunity to attend Team Topologies Fundamentals training in Leeds - the session was delivered by Matthew Skelton. Together with Manuel Pais he wrote a book called Team Topologies that discusses how to "build the best team organization for your specific goals, culture, and needs".
The training was organised into 4 sections:
Teams and Conway’s Law
Fundamental Toplogies
Team Interaction Patterns
Evolving Team Topologies
Both the book and content of the training are based on 5 years of research across 30+ organisation in multiple industries and various countries / cultures. The authors focused on distilling underlying principles, patterns and topologies. This allowed them to focus on the essence of team design, rather than on more specific challenges related to a particular industry.
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