I have been trying to figure out the preferred way of doing "Event Sourcing" while using the NestJS CQRS recipe (https://docs.nestjs.com/recipes/cqrs). I've been looking at the NestJS fra...

I am using Kafka for Event Sourcing and I am interested in implementing sagas using Kafka. Any best practices on how to do this? The Commander pattern mentioned here seems close to the architecture...

What is the difference between CQRS (Command Query Responsibility Segregation) and Event Sourcing? I believe Event Sourcing is a type of CQRS. What distinguishes each, and what makes Event Sourcin...

I was looking in to event base architecture and came to know about two architecture Event Sourcing & Event Driven Architecture. My understanding is following Event driven : used for distribute...

I'm working with event sourced data where all of the important fields are combined to a JSONB column and many of the keys are missing from most of the database rows. I would want to get: Aggregate...

I know that CQRS can be implemented with or without event sourcing, but does it work the other side? Does event sourcing without CQRS make sense? If so, how it should be implemented?

I am trying to learn about microservices, and am confused about which approach is better between service orchestration and event sourcing ( service choreography) . There seems to be very few framew...

OpenAPI is good for RESTful services and at the moment, I'm hacking it to do it for asynchronous messaging system (specifically Kafka) by using POST to a /topic so that I can use redoc do create a ...

I'm currently evaluating options for designing/implementing Event Sourcing + CQRS architectural approach to system design. Since we want to use Apache Kafka for other aspects (normal pub-sub messag...

I am trying to implement event sourcing/CQRS/DDD for the first time, mostly for learning purposes, where there is the idea of an event store and a message queue such as Apache Kafka, and you have e...

Although I've come across Kafka before, I just recently realized Kafka may perhaps be used as (the basis of) a CQRS, eventstore. One of the main points that Kafka supports: Event capturing/storing...

I'm working on an application for managing bank credit cards. CQRS and Event Sourcing architecture was chosen for the app. The most important aggregate in the app is CreditCard which controls the c...

When we talk about sourcing events, we have a simple dual write architecture where we can write to database and then write the events to a queue like Kafka. Other downstream systems can read those ...

I am interested in how others have handled a Read Side DB update failure in CQRS/Event Sourcing eventually consistent systems. I have such a system that could append an event to my event store, an...

I am just starting with the CQRS, Event Sourcing. While examining many frameworks, I have realized that one of the thing most of the frameworks assumed that our application is modelled based on the...

So we have a couple of lambdas that listen to changes on the db, in every lambda we had to filter in the beginning because this particular lambda don't care about all changes just a particular one....

I am currently working on a monolithic system which I would like to bring into the modern day and incorporate DDD and CQRS. I have been presented with a request to re-write the importing mechanism ...

As a software project built on an event sourcing architecture evolves, the event schema (or event types) are among the things most likely to change over time. One of the benefits event sourcing arc...

Could any one explain why there are 2 actual versions of EventStore (20.6.1 and 5.0.9)? What is the difference between them ? What version for what goals should we use?

As far as my little current experience allows me to understand, one of the core concepts about "microservice" is that it relies on its own database which is independent from other microservices. D...

The situation is as follows. There are three services, one service is event sourced and publishes integration or notification events (outbox pattern) to the other two services (subscribers) using a...

I am playing with EventStore. As a .NET user I prefer Windows as OS, only that I have home edition. In order to install Docker I need Windows Proffessional Edition - and I don't have it ... it's ou...

Presumably we could resurrect state by applying the same set of commands, so why not simply store commands rather than events?

I've read this nice post from Jonathan Oliver about handling out of order events. http://blog.jonathanoliver.com/cqrs-out-of-sequence-messages-and-read-models/ The solution that we use is to de...

I'm creating a tiny event-sourcing-style function app, where every invocation of a function will write an event to table storage. An example of such an event would be: +------------+--------------...