Event Sourcing applied – the Aggregate

This is my 100th post – I have to open a good bottle of wine tonight! In my last post I was presenting my thoughts about event sourcing (ES) as an architectural pattern. In this post I want to show in … Continue reading 

Posted in Uncategorized | 7 Comments

Event sourcing revisited

Event Sourcing (ES) over the last few years has become one of my favorite architectural patterns when implementing a complex line of business (LOB) application or a complex component making part of a LOB application. Attention – paradigm change! It … Continue reading 

Posted in architecture, DDD, design, Event sourcing, How To | 26 Comments

DDD – The aggregate

In my last posts I revisited domain driven design (DDD), applied it to a concrete domain and shed some light onto special scenarios (here and here) and how one could possibly solve them using DDD. In this post I want … Continue reading 

Posted in architecture, DDD, design, How To, patterns, TDD | 22 Comments

DDD – Special scenarios, part 2

In my last post I discussed possible solutions for two specific problems when using DDD. In this post I want to analyze more Collaboration of aggregates Aggregates in DDD are very self centric or self focused. An aggregate does not … Continue reading 

Posted in architecture, DDD, design, How To, practices | 15 Comments

DDD – Special scenarios, part 1

Introduction In the last two posts (here and here) I first revisited domain driven design (DDD) in general and then I showed how we apply DDD on a realistic sample domain. For most people DDD sounds very compelling but as … Continue reading 

Posted in DDD, design, How To, practices | 29 Comments

DDD applied

Introduction In my last post DDD revisited I talked about what is important when using domain driven design (DDD) as an architectural pattern. I have had the pleasant surprise that this post was event mentioned on InfoQ. Today I want … Continue reading 

Posted in architecture, DDD, How To | 24 Comments

CQRS Workshop – Retrospective

Introduction Today I had the honor of leading the first of a series of workshops at ClearMeasure. The topic of this workshop was CQRS. After a brief introduction into the topic the attendees were working in teams of 2 to … Continue reading 

Posted in architecture, CQRS, design, How To, introduction, learning, practices, workshop | 6 Comments

DDD revisited

Introduction Way too many times I encounter applications that claim to have a domain (model) and that domain driven design has been used to develop it, but in reality what I find is a collection of entities or shall I … Continue reading 

Posted in DDD, design, How To, practices | 10 Comments

Welcome Andrew Siemer

It is a pleasure to me to welcome Andrew Siemer as a new member of LosTechies. Andy is my coworker and chief architect at ClearMeasure. Before joining ClearMeasure he was chief architect at Dell. Andy is an ASP.NET Insider and … Continue reading 

Posted in Uncategorized | 1 Comment

CQRS applied

In this post I have discussed CQRS, an architectural pattern from a high level perspective. CQRS is one of my favorite patterns when it comes to complex line of business applications. Let’s discuss CQRS on a specific sample. Imagine we … Continue reading 

Posted in architecture, commands, CQRS, design, queries, Read model, REST | 31 Comments