One huge problem with building microservices is how they are used in new solutions without gradually turning the shiny, separated, autonomous services into slow-to-change, hard-to-regression test, inter-dependent big balls of mud There is this temptation to wire things up and make changes to expand our services to fit a new solution, however this can quickly…More
Category Archives: Microservices
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
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
Understanding Error Handling in Integrated Solution: Making things robust
Integration engineering regardless of the architectural style (EAI, microservices, SOA, accident etc) must ensure the end solution is robust and reliable. These are two key attributes of any solution and rely on handling scenarios when things do not go exactly as planned when two systems talk to each other over a network Planning for unexpected…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
Capturing the essence of your software with diagrams: Techniques for the engineer, designer and architect
Pictures are “worth a a thousand words” and in the software industry they can save time and help inspire the collective imagination A good picture about a software system at right level can convey the right details. It is about what you leave out as much as what you put in and structure – there…More
Messaging, Events and Data-in-Motion: Asynchronous communication patterns
When integrating systems we often end-up writing asynchronous messaging interfaces for mostly system-to-system communications. This conversation technique is great because it does not require the sender and receiver to stay connected to each other in a session at the same instance in time, it is non-blocking and often brokered (like the post office which brokers…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
Building strategic public and partner API experience: The power of experience adapter and an abstraction layer
As organisations look to take their offerings to the world outside for specific customers, partners or general public and grow their business, they must balance the risk of opening the door to internal mission-critical systems vs value provided. These offerings also must deliver the right experience, requiring an abstraction over the internal organisation services to…More
Common Service Caching Patterns
Caché implies to hide something. In a technology context this is “some service hides some data for a period of time (minutes to years)” A cache is a bit of information we stash away to better serve the clients using our service. Some of the questions cache implementers face are: Cache expiry and invalidation Mechanism…More
Choosing the right tool for Stateful orchestration: Embedded Process Engines vs Serverless Step Functions
Just based on recent experience, I am going to put this out there – AWS Step Functions are great for technical state machines which move from one-activity to another but not really designed for stateful process orchestration and definitely not for implementing SAGA Serverless Step Functions from AWS or BPMN Engines? When building microservices, the…More
Single Entity, Multiple Master: Manage Complexity with Domain Services Integration Pattern
We often think of enterprise systems as the master systems for one or more enterprise data entities. We believe the lifecycle of the entity is contained and managed by users in a system in an encapsulated and convenient manner. However, there are scenarios where multiple systems master an entity and this is often because they…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
Domains, Sub-Domains and Bounded Contexts: Explained with example from industry
The Domain Driven Design (DDD) book and community use the language of Domains and Bounded Contexts. Often there is confusion around what is a Domain, Sub-Domain, Bounded Context and how do we tell the difference between one or other when we are in the trenches. This confusion can lead to poor design where our domain…More
A Pandemic, Open APIs and Citizen Science: Its 2020 baby!
Human societies have been hit by pandemics through the ages and relied on the central governing authorities to manage the crisis and disseminate information. I believe this time around with COVID-19, our societies have access to more information from our governments because we have the internet If this pandemic is an evolutionary challenge, then our…More
Coordinating Distributed Software: Choreography vs Orchestration
There are 2 ways of coordinating distributed systems and services to achieve an end-to-end outcome More
Observability in distributed systems: Monitoring, Logging, Auditing and Historical analysis
“Knowing the quality of your services at any given moment in time before your customers do and using this information to continuously improve customer experience is part of modern software delivery and critical to the success of organisations” In this post, we present why it is important to observe and manage our systems and solutions proactively and…More
De-mystifying the Enterprise Application Integration (EAI) landscape: Actors, terminology, cadence and protocols
Any form of Enterprise Application Integration (EAI) [1] work for data synchronization, digital transformation or customer self-service web implementation involves communication between the service providers and service consumers. A web of connections grows over time between systems, facilitated by tools specialising in “system-integration”; this article covers how the clients, services and integration tools communicate and…More
Tackling complexity: Using Process maps to improve visibility of integrated system features
“Entropy always increases “– second law of thermodynamics Enterprise systems are similar to isolated physical systems, where the entropy or hidden-information always increases. As the business grows, our technology footprint grows as new systems are implemented, new products and cross-functional features are imagined and an amazing network of integrations emerge Knowing how information flows and…More