#eventsourcing — Public Fediverse posts

Reminder that tonight I'm speaking in Hamburg (at the Microservices Meetup) about #EventSourcing! I know it's short-notice, but if you're around, come on by and let me share with you my passion on the topic! https://www.meetup.com/microservices-meetup-hamburg/events/316350578/

Me and #EventSourcing a year ago

[edit: added that this turned into an obsession for me about a year ago]

Hey folks, guess what? I'm speaking on Thursday (3 Sept) in Hamburg (at the Microservices Meetup) about #EventSourcing! I know it's short-notice, but if you're around, come on by and let me share with you my passion on the topic. https://www.meetup.com/microservices-meetup-hamburg/events/316350578/

Tested an idea I had for teaching aspects of #EventSourcing by having folks role-play as different components (read model, processor) and I think it worked! Thanks to my SoCraTes Germany guinea pigs for participating, I hope it helped you understand things better.

My book club is reading Designing Data-Intensive Applications (by Chris Riccomini and @martin) and today we went over the bulk of Chapter 13 and all I can say is WOW!

Dataflow-oriented systems, of which #eventsourcing is very much in line with those ideas, give up a bit in "timeliness" (aka consistency lag, aka eventual consistency), but give you solid integrity and can help sidestep coordination, making distributed systems easier to reason about and perform better than overcomplicated transactions and consensus systems.

I can't wait to add some of the insights from this chapter into my Ted Talk on Event Sourcing.

I wrote a small blog post about the new release of patchlevel/event-sourcing-phpstan-extension, 1.3.0 adds three new rules.

They report aggregate properties that no event ever fills, state that nothing ever reads, and state that changes outside an apply method.

Also, every rule can be turned off individually.

Feel free to check it out!

https://patchlevel.dev/blog/what-is-new-in-the-event-sourcing-phpstan-extension-1-3-0

#TechBlog #PHP #DDD #EventSourcing #PHPStan #StaticAnalysis

In this #InfoQ podcast, Johannes Schickling explains why he moved beyond the traditional three-tier web stack to a local-first architecture while building Overtone.

Learn how client-side event sourcing with SQLite compares to CRDTs, and the trade-offs architects should consider.

🎧 Listen now (transcript included) 👉 https://bit.ly/4pIHM6N

#LocalFirst #SQLite #EventSourcing #SoftwareArchitecture

CQRS, async with retries and dead-lettering, event sourcing, projections, workflows. That feature list usually means a platform team.

I built it as an e-commerce shop on Tempest + Ecotone. The entire messaging layer: about a dozen small classes of business logic. No worker command, no repository, no queue wiring.

The Order aggregate IS the Tempest database model. One class, both frameworks.

https://github.com/ecotoneframework/tempest-ecotone-demo

#PHP #CQRS #EventSourcing

Requirements change, but your events are immutable and your history lives forever. So how do you evolve them without breaking anything?

I just published the second and final part of my two-part series on event design: "Evolving Your Events Over Time." It walks through the whole toolbox of event evolution, from a free rename to rebuilding the whole store.

Feel free to check it out!

https://patchlevel.dev/blog/evolving-your-events-over-time

#TechBlog #PHP #DDD #EventSourcing #EventDesign

We released 3.17.1 of event-sourcing-bundle! See here for the changelog: https://github.com/patchlevel/event-sourcing-bundle/releases/tag/3.17.1
#PHP #DDD #EventSourcing #Symfony

RE: https://floss.social/@monospace/116923591603748773

We (should) do this for configuration, why not for the application data, too? #EventSourcing

In part 13 of my event sourcing series, we take a look at how to undo bi-temporal events (why and how):

https://www.planetgeek.ch/2026/07/14/event-sourcing-undo-set-remove-based-bi-temporal-events-because-we-must/

After this post, there will be a summer break.

#EventSourcing #fsharp

We just published *Cutting Your Events the Right Way*, the first part of a two-part series on event design.

It takes the same customer data, models it as one big event and as several small ones, and works out when each cut is the right call.

Read it here: https://patchlevel.dev/blog/cutting-your-events-the-right-way

#EventSourcing #DDD #PHP #SoftwareArchitecture #EventDriven #TechBlog

Back to bi-temporal events in part 12 of my event sourcing blog post series: https://www.planetgeek.ch/2026/07/07/event-sourcing-set-and-remove-based-bi-temporal-events/

This time, we look at set-and-remove-based bi-temporal events - the second variant of bi-temporal events in our system. You'll see why they are needed, and what additional problems this kind of event brings to the table.

#EventSourcing #dotnet #fsharp

Version 3.20.0 of patchlevel/event-sourcing is out! You can now keep reading old messages whose header classes were removed, and the destructive CLI commands accept a `--force` flag so you can run them from scripts and pipelines.

I wrote a blog post about the release, feel free to check it out!

https://patchlevel.dev/blog/what-is-new-in-php-event-sourcing-3-20

#TechBlog #PHP #DDD #EventSourcing

We launched patchlevel.dev a couple of weeks ago! Our open source PHP event-sourcing ecosystem was scattered across
separate MkDocs sites, a blog on our consultancy site, and GitHub READMEs.

Now everything lives in one place: the event-sourcing library, the Symfony and Laravel integrations, and all supporting
libraries side by side. Plus unified search across docs and blog, and docs that stay in sync with every release.

Have a look: https://patchlevel.dev

#PHP #EventSourcing #OpenSource

This is coming up soon! Join me on Monday for my Ted Talk at OpenValue in Munich:
https://www.meetup.com/openvaluemuenchen/events/315218662

And you can check out my event-sourced travel app at http://jittertravel.com/calendar

#EventSourcing

My answer to a lot of questions I get about #EventSourcing seems to be “well, what do you do now?” And then I add, “with event-sourcing, it’s probably easier to fix/recover/adapt/etc.”

We released 3.19.2 of event-sourcing! See here for the changelog: https://github.com/patchlevel/event-sourcing/releases/tag/3.19.2
#PHP #DDD #EventSourcing

In part 11 of my event sourcing series, I discuss consistency and why we don't use aggregates or dynamic consistency boundaries to solve it:

https://www.planetgeek.ch/2026/06/23/event-sourcing-aggregates-dynamic-consistency-boundaries-or-what/

#EventSourcing #dotnet #fsharp

A lot has happened since our last release post: eight minor releases for patchlevel/event-sourcing, from 3.12 to 3.19.

Instant retry command bus, subscription cleanup, auto initialized aggregates, PHP 8.5 and Symfony 8 support and much more.

Feel free to check it out!

https://patchlevel.dev/blog/what-is-new-in-php-event-sourcing-3-12-to-3-19?utm_source=mastodon&utm_medium=social&utm_campaign=blog

#TechBlog #PHP #DDD #EventSourcing

Event sourcing is easy. Just store what happened to a thing as events, and when you need the thing's state, project the events. Unless it is not because there are misplaced or duplicated events in the event stream. In the tenth part of my event sourcing series, we'll look at why events can be misplaced and how to handle them.
https://www.planetgeek.ch/2026/06/16/event-sourcing-temporally-misplaced-or-duplicated-events/

#EventSourcing #dotnet #fsharp

Part nine in my event sourcing post series is about mixing bi-temporal and uni-temporal events in the same event stream. Why, how, and the trade-offs.

https://www.planetgeek.ch/2026/06/09/event-sourcing-non-bi-temporal-events-in-a-bi-temporal-stream/

#EventSourcing #dotnet #fsharp

If you're following my ongoing blog post series on event sourcing and have any questions, feel free to ask here or in the post comments.
The question does not have to be about event sourcing. I'm especially happy to answer questions about the F# samples.

https://www.planetgeek.ch/tag/event-sourcing/

#EventSourcing #fsharp #dotnet

Join me in Gembloux, Belgium on 9 June at the Belgian #Java User Group for my Ted Talk on #EventSourcing! Gonna squeeze a year of learnings into 45 minutes (we'll see how that goes).

Details here: https://www.meetup.com/belgian-java-user-group/events/314996280/

We released 3.17.0 of event-sourcing-bundle! See here for the changelog: https://github.com/patchlevel/event-sourcing-bundle/releases/tag/3.17.0
#PHP #DDD #EventSourcing #Symfony

In part eight of my event sourcing blog post series, it's time to look at bi-temporal event sourcing. At least we start with the very basics. Why we need it and how it works.
https://www.planetgeek.ch/2026/06/02/event-sourcing-the-not-so-simple-bi-temporal-basics/

#EventSourcing #dotnet #fsharp

New blog post: My Work in Progress Ruby stack ismaelcelis.com/posts/2026-0... #eventsourcing #cqrs

My WIP Ruby stack

I have been iterating on Event Sourcing and CQRS architectures for nearly a decade. When I first started with this pattern around 2016 and 2017, the implementation was considerably more complex. Over the years I have stripped it back again and again, and what I have arrived at now is something I'm genuinely happy with: a small, focused TypeScript library backed by DynamoDB that does exactly what it needs to and nothing more: https://coderbyheart.com/es-and-cqrs-on-aws-simplified #eventsourcing #cqrs #aws

RE: https://mastodon.social/@venkats/116568410481331830

I’m not only presenting two talks (one is a game, guess what it is), but also thrilled to do a workshop on my current passion: #EventSourcing and #DomainDrivenDesign #Java

Your customer received €50. The notification on their phone says "New balance: €100." Should be €150 — the notification queried the read model before the projection committed.

That race lives in most CQRS systems. Wrote up how to close it for good in PHP — by emitting derived events from inside the projection.

https://blog.ecotone.tech/stop-subscribing-to-domain-events

#PHP #EventSourcing #CQRS #Ecotone

Next week I will speak at BASTA! Conference in Frankfurt, about #SoftwareArchitecture, #CSharp, #LLM use in #CQRS and #EventSourcing systems, and much else. 🌎 Bring your thinking hat for my #BASTAllionaire game show 🎉! Say hello if you see me, or come talk about #DevExpress. 🚀 https://basta.net/frankfurt/

I've developed #Ecotone Framework based on the principle that we should fully focus on business features, not the technical infrastructure part.

However, in some cases where optimization of requests is critical, auto-initialization may come with a performance penalty.

For this #Ecotone provides now migrations, that can help optimize this process:

https://docs.ecotone.tech/modelling/migrations-storage

#PHP #Messaging #CQRS #EventSourcing #DDD #SoftwareArchitecture

I broke down Event Sourcing in Quarkus using Java records, sealed types, pure functions, and a clean CQRS split.

Fully hands-on. No magic. Just data, folds, and clear architecture.
If you want to understand event sourcing without the hype, this one is for you.

👉 https://www.the-main-thread.com/p/event-sourcing-quarkus-java-records-cqrs-tutorial

#Java #Quarkus #EventSourcing #CQRS #DataOrientedDesign

1) Understand the domain
2) Domain modelling (#ModelInCode)
3) Let a test drive us (#TDD)
4) Implement the controller
5) Drive the core implementation by a test (TDD again)
6) Extend the business logic facade (#HexagonalArchitecture)
7) Implement the command
8) Implement the event projection (#EventSourcing)
9) Implement the database access (#OnionArchitecture)
10) Release it (#CI_CD)
11) See your changes at work (#REPL #FSI)

With code samples in #dotnet