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

Consistent or not that’s the question

My last post about CQRS has lead to a lively discussion around eventual consistent read models. First let me clarify what eventual consistency in the context of a read model means. A read model that needs some time to get … Continue reading 

Posted in asynchronous, CQRS, Event sourcing, patterns, Read model | 6 Comments

CQRS revisited

Introduction In my opinion Command Query Responsibility Segregation (CQRS) is one of the most useful architectural patterns when used in the context of a complex line of business application (LOB). Martin Fowler writes … At its heart is a simple … Continue reading 

Posted in architecture, CQRS, How To, learning, patterns | 54 Comments

Creating an Angular application end-2-end – Part 3

Introduction In the last two posts of this series which you can find here and here I started to implement the server side of a complete Angular JS application that uses CQRS and Event Sourcing as architectural patterns and stores … Continue reading 

Posted in Event sourcing, GetEventStore, How To, introduction, MongoDB, Read model, Ubuntu | 2 Comments

Starting a new adventure

Looking back I’ve been working as an architect and chief architect for TOPAZ Technologies LLC more than 6 years. It has been an exciting time and I have learned a lot. In 2009 I inherited an enterprise application that, let’s … Continue reading 

Posted in hiring, job, learning, personal | 3 Comments

Writing an Angular JS application end-2-end–Part 2

Introduction In the previous post I showed how we can use Yeoman to scaffold a new ASP.NET vNext application on Ubuntu. I then implemented a simple RESTful API and also started to implement the basics of a domain model. In … Continue reading 

Posted in ASP.NET vNext, CQRS, Event sourcing, GetEventStore, How To, introduction, REST, Ubuntu | 5 Comments