Eventually Inconsistent

The question isn’t whether you are ready for AI. It’s whether your data is. Because some organizations have been recording their history for years — and others are still only keeping snapshots. The difference doesn’t show much today, but it soon will. Where AI meets Event Sourcing Last week I attended the AXONIQ Conference in Amsterdam, where the main theme was  “Where AI meets Event Sourcing.” It wasn’t my first time at that conference — but this time I joined literal round-table discussions . Architects, C-level leaders, and AI specialists sitting together, finally having the kind of conversations that felt overdue. Those discussions were eye-opening — not because of any new revelation about AI itself, but because it became clear what Event Sourcing has quietly been preparing us for all along. Decades of recording intent, state changes, and causality — and only now the world is catching up to why that matters. The gap is already here I’m not an AI expert. But I am a...

 Almost three weeks ago, I participated in an internal AI hackathon. The idea was simple: one day to work on any work-related project, with one constraint — rely almost entirely on AI to do the work. Code generation, design help, scaffolding, naming things, documentation, the works. Naturally, I didn’t pick something easy. I decided to refactor a core part of our system — something foundational, messy, and grown over time. You know me — if there’s domain complexity, some bounded context hairball, or a little #DDDesign chaos to untangle, I’m in. It was the first time I leaned this heavily on AI in one go. Here’s what I learned. If someone tells you AI is writing ALL their code — be skeptical. In some corners of the internet, it sounds like AI can just build entire systems from scratch. In reality? If AI is writing everything for someone, either the task is trivial, or they’re cutting corners you probably don’t want to cut. In my case, the domain was non-trivial, the logic...

💥  Krótkie ogłoszenie: Powoli pracuję nad swoim kursem online o nazwie: DDD/CQRS/ES Applied on JVM with Axon Framework Jeśli jesteś Programistą, Team Leaderem, lub Architektem i chcesz W KOŃCU wprowadzić Domain-Driven Design , Command Query Responsibility Segragation , Event Sourcing do Twojego systemu opartego o platformę JVM - zarówno legacy , jak i greenfield - to na pewno będzie to coś dla Ciebie ! Kurs będzie startował w języku polskim niebawem, a tymczasem... Dołącz już dziś do listy oczekujących, a następnie pobierz darmowy Ebook " 4 narzędzia do DDD/CQRS/ES na platformie Java " (* Plus jedno, błędnie za takie postrzegane - BONUS!) Sprawdź:  cqrsapplied.pl Do zobaczenia niebawem!

At the beginning of this year, I launched my personal website patternapplied.com (for English version patternapplied.com/en ).  I specialize in Domain-Driven Design, Command Query Responsibility Segregation, Event Sourcing on the JVM platform and with 10 years of experience in that field and the knowledge gathered over this time, I finally feel prepared and ready to share it with a broader audience . I should have done this a gazillion years ago, but hey… better late than never.  The story I’ve been doing Domain-Driven Design since 2011. During this time I was able to truly dig deep into this topic, since I was working mainly on a single product in an extremely complex and dynamic domain. Our team was responsible for delivering a new solution (next to the existing one) in the Core Domain of this product. One might say that this was a rewrite of a Legacy System, but it wasn’t. The other part of the system was still profitable. It was just doing things in a less automated and l...

It's been 3,5 years since I gave the last public talk... Way... too... long... So it has to change. And it will! I invite you to a really  innovative conference  for software architects:  SegFault Wrocław . Let's get back to the basics again. I'm going to be speaking about " Using Domain-Driven Design in legacy systems ". There will be some other experienced speakers, with a lot of knowledge gathered while working on  production systems  (not read from a book), so the event is quite unique. I'm looking forward to meeting you there! PS. I will have another announcement soon, so stay tuned...

Last week, I attended the Software Craftsmanship Kraków meetup, where we discussed "Life beyond Distributed Transactions: an Apostate’s Opinion" article by Pat Helland. Author tries to tackle the problem of almost-infinite scaling of applications. He ignores such issues like high availability on purpose and focuses only on scalability alone. That makes the essay easier to read – even for junior developer. Although the author does not say it explicitly, there are a lot of similarities between presented concepts and Aggregates from Domain-Driven Design . Pat's paper was written in 2007, so my wild guess is that he might have been familiar with Eric's book, which was published in 2004. Since there are still a lot of questions regarding Aggregate's boundaries (and technical difficulties arising around them) in DDD world, I recommend Pat's article as a complementary reading, which takes more infrastructure-oriented approach and may clarify some things.