Category Archives: Domain Driven Design

Are your streams noisy?

As event-driven platform take off ✈️ with modern integration practices such as data-in-motion, organisations are integrating significantly large number of data and event streams 📈 without deliberate and up front design these growing streams are contributing to noise, complexity and coupling leading to higher implementation (CAPEX) and operating (OPEX) costs. In this post we look…More

Strategic DDD Outcomes: Top Domain model to Team Topologies

Over the past couple of years, I have been working with architecture and engineering teams to teach and apply strategic and tactical domain driven design. I will come back with lessons learned in a future post, but this one covers the outcome of these teaching plus consulting engagements for strategic DDD Remember, strategic DDD is…More

Technology Service Modernization (Part I): 3 Approaches to Modernization

Welcome to 2022. While I was in a blogging hiatus, my time was spent closing out conversations with business and technology leaders looking to modernize their technology solutions as they were looking to adapt them new market needs and challenges. I thought Web3.0 was the big buzz word but it looks like Modernization is the…More

The Domain Stories Series: Search Story

A common story we often hear is related to searching for information. This is a powerful capability to provide through your technology services as the user is keen to interact with your offering and the richer and performant it is, the more value the consumer draws from this. Google it! When analysing the search story,…More

Domain Model != Data Model

One of the smells when practicing DDD (Domain Driven Design) is when you are presented with a Data Model (extracted from an existing set of tables or constructed through rigorous but confirmed hypotheses) and asked to consider this as your Domain Model Domain Model is not the same as a Data Model This is an…More

Business Services and APIs: 101

Business oriented service design and implementation is becoming increasing popular with organisations looking to move beyond traditional systems integration led services. This top-down approach needs to start with business domain owners and their processes, documenting the core and supporting business capabilities they present to their customers so that they can be analysed to produce technology…More

DDD Anti-patterns: 5 things we get wrong with Domain Driven Design in practice

As a software architect I have been using various design techniques including Domain Driven Design (DDD) which has been incredibly useful for building APIs and Microservices and for strategic architecture consulting engagements requiring discovery/mapping of socio-technical organisation structure and in documenting an API strategy I have also been training architects across organisations to understand and…More

Mapping Business Capabilities to Services

One of the key questions around API strategy we get asked is how do we map business capabilities to services. An approach is to use domain driven design and build domain services, in this post we will look at what this looks like Capabilities Businesses domains offer capabilities. Given domains are classified into core, supporting…More

Iterative Domain Model Design: How to stay autonomous

One key question that I hear with Domain Modelling is how do you know if you have your transaction boundary right (so that you build the right aggregate)?  Hidden in this is another question – what if we got our domain aggregate wrong? We can take this further and ask In an agile world, given change…More

Domain Driven Design (DDD): Core concepts and Enterprise Architecture

If you are building or designing APIs, Microservices or integrating systems then Domain Driven Design (DDD) offers a valuable design technique for mapping business domains to build software services of value Using DDD is incredibly useful when designing services because it helps you rationalise the granularity of your software, the ownership boundaries and model interactions…More

DDD Context Mapping By Example: Customer Management and Customer 360

In the continuation from the previous post, here we look at how to do context mapping from sample real-world examples. In this post we look at how to model Customer Management from a customer support perspective and how Customer 360 would look like as a context map With this post, I hope to give you…More

DDD Context Mapping by example: Policy Management

DDD context mapping can be confusing without real-world examples. In this post we will model sample implementations for two scenarios using bounded context maps and learn to analyse the relationships from the maps. With this post, I hope to give you a fair idea of how to do apply DDD into build good distributed features…More

User Journey, User Story vs Domain Story: What’s the difference?

While running DDD workshops with clients, I have had this question come up several times – “What is the difference between a Domain story vs a User Story?” Here is a quick look at differences: User journey story: Is a technique for describing how the user interacts with our business (and business systems) over time…More

Software Monoliths

Companies need to modernize software and engineering to scale to reach new customers. Many find it increasingly hard to deliver outcomes safer and faster in a rapidly changing business ecosystem because of internal complexity from existing practices, systems and integrations. One cause is “shared” collaboration of resources between teams and in this post we explore these monoliths and monolithic practices More

Domain Service Design and Patterns

Domain services implement core logic for a business domain and are a relied upon by experience and consumer services. Domain services can be self contained and store the business logic and state or rely on an external provider system (translating from a “raw system format” to a “canonical” domain format) In this post we look…More

From Project to Product Teams: Implementing the Inverse Conway Move for better Software

Modern software engineering techniques within organisations deliver “distributed features” using agile techniques. These features are distributed across different systems and integrated to provide an end-to-end experience. Traditional project delivery brings in  members from different system oriented teams to deliver these features in a loose and ad-hoc fashion and dis-bands the team after a project is…More