One of the challenges of designing distributed systems is balancing the local and global complexity. In some cases, we might want to reduce the local complexity (and cognitive load) by splitting a single system into multiple smaller ones, that are going to be loosely coupled.
That often brings a problem of managing the specification of behaviours of the subsystems in the context of the whole system. Usually, we want to have the specification consistent between the subsystems, but at the same time keep them loosely coupled and independent.
Read moreThere is quite a lot of confusion in the community with regards to EventStoreDB and Kafka - especially when it comes to event sourcing. Developers not familiar with both products are having a hard time deciding which technology they should use, how do they compare and what are the trade-offs that they will have to make.
In this article, you will learn what the two solutions offer, how to use them effectively, and when to use one over the other. In order to do that, we first need to agree on the definition of event sourcing and requirements that the solution should meet.
Read moreIn an Event Sourced system, the current state of an aggregate is usually reconstituted from the full history of events. It means that before handling a command we need to do a full read of a single fine-grained stream and transport the events over the network. For a well-designed aggregate, it’s usually not a problem as it’s lifecycle is bounded to a specific time period and the number of events doesn’t grow indefinitely. But what if our design isn’t optimal, or we have some outliers that are requiring thousands of events to be transported every time we want to handle a command?
Read moreOne of the topics that came up a few times (and I noticed quite a number of searches for it) is how the Aggregates and Projections differ or relate to each other. The reason for this confusion is that some parts of the implementation logic are very similar - in particular, the current state of an Aggregate derived from the event log. In this blog post, we will explore the differences and look at some examples.
Read moreSome of you found yourself in a situation, where your company asked you to start working remotely very suddenly. Some of you were already working partially or mostly remotely for some time and found ways of dealing with the challenges it presents. No matter which group you are identifying with - remote communication and modelling isn’t always easy, and each day brings new ideas, tools, discoveries, and challenges.
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