An integrated architecture with autonomous domains and information sharing


Home Affairs is a very large organisation that includes Immigration, Customs, Policing and Intelligence. The department presents unique ICT challenges, including 1000+ distinct integrations between 200+ IT systems accessed by 30,000+ users.

In recognition of the demands of scaling such a complex framework, Home Affairs released a 2020 technology strategy that identified the need for autonomy/agility and quality centralised intelligence information for border risk decision making. It highlighted a new integration strategy as key to achieving both goals.

Based on a centralised enterprise service bus design and implementation function, most legacy integrations were established with ad-hoc project needs defined late in each project lifecycle. The result was a patchwork of tightly coupled systems where each service was designed for specific needs with little reuse.

Tight coupling between systems imposes complex dependencies and severely limits agility. With system integration previously considered as a purely technical activity, GoSource drove thought change across IT system teams and executive.


To begin, GoSource developed a high-level ‘Why What How’ slide deck to drive executive support, which led to senior approval and capital funding. They used tangible examples and prototypes to garner support from business domains and IT system owners for the integration strategy.

A top-down domain and resource architecture defined the required micro-service granularity. This called for teams to consider positioning their services for self-service consumption by other business units.

GoSource designed and prototyped shared technology platforms such as the API gateway and enterprise event hub using AWS platform services including API Gateway, Lambda, S3 and kinesis.


GoSource provided advice and support to each business domain, empowering them to design and implement REST microservices and events within the centrally governed high-level domain architecture.

Having engaged more than 20 business domains and analysed the current state, the team documented the integration architecture and produced both a detailed document and a compelling one-page poster to engage business areas throughout the department.

These changes have made significant progress in establishing an integrated technology environment for the department. Developing self-contained systems that focus on domain-specific business logic, rules and processes, while sharing common services, provide the flexibility the department needs to adapt systems to changes in their operating environment.

Department of Home Affairs
Six months
GoSource provided strategy and support through a senior architect plus a modeler and API developer
A new integration strategy for Home Affairs has empowered each business domain to design representational state transfer (REST) microservices
In brief


  • Capability building GoSource empowered IT teams by building their skill set in the decentralised delivery model for microservice design and implementation.
  • Reduced complexity The project reduced the more than 700 enterprise service bus transformations to 16 resources in five domains with enhanced autonomy.
"GoSource helped us sweep away a spider’s web of complexity by designing a new integration architecture that supports both agility and insights."
Lindsay Smith, Director of enterprise architecture,
Department of home affairs