Last month, I published an article that sought to introduce sustainability as another quality attribute architects consider when evaluating stakeholder needs to produce software solutions. Sustainability’s importance should require no emphasis or justification. I choose to believe the scientific method has spoken. The evidence is empirical. Our abode is in trouble, and the time to act is about to lapse. As such, I speculated that AWS would soon recognise its significance by incorporating sustainability as an evaluation perspective within the AWS Well-Architected Framework.

The annual AWS re:Invent conference took place in early December, and with it came the welcomed news of a sixth pillar in the AWS Well-Architected Framework. Yes, partner-led AWS architecture assessments will now cover sustainability. So, the announcement presents an opportune moment to revisit the topic and reflect on this exciting development.

AWS’ guided approach to sustainability is to understand and qualify the environmental impacts of service adoption on the entire workload lifecycle and seek to reduce the extent by applying design principles and best practices.

“AWS has taken a similarly balanced approach to sustainability.”

The AWS ‘Shared Responsibility Model for Security’ is well known. The model delineates the security aspects that AWS manages on behalf of customers and the parts that remain a customer’s obligation. For example, a benefit of public cloud adoption originates from the operational burden taken on by providers through their management and securing of cloud infrastructure and services. This position refocuses customer attention to ensuring the integrity of workloads placed on top of this footing. AWS has taken a similarly balanced approach to sustainability. AWS contributes by allowing customers to reduce workload energy consumption by approximately 80% compared to traditional on-premises environments. This benefit stems from optimal server utilisation rates with efficient cooling and the advancement towards fully leveraging renewable power by 2025. Customers must comprehend their workload state, track sustainability targets, and manipulate behaviour and resource usage to improve efficiency.

The new pillar delivers design principles, operational guidance and best-practices patterns for architecture and design.

A summary of the principles that promote good design are:

  • Measure the sustainability impact of business outcomes.
  • Establish long-term workload sustainability goals and compensate for growth.
  • Maximise resource utilisation through workload ‘right-sizing’ and appropriate hardware selection.
  • Adopt alternative hardware or software offerings that are more efficient.
  • Leverage managed services to reduce infrastructure usage further.
  • Reduce the energy and resources consumed on end-user devices.

Examples of complementary architectural best practices include:

  • Refactor code areas that consume excessive execution time and resources.
  • Relocate workloads geographically closer to end-users.
  • Remove excess data using lifecycle policies.
  • Reduce data transversal distances.
  • Increase build environment utilisation.
  • Justify the use of inefficient resources such as GPUs.
  • Optimise ‘downstream’ energy consumption on user equipment.
  • Incorporate development and testing strategies that support sustainability improvements.

“Anything less would have been akin to paying ‘lip-service’ to such a critical subject.”

AWS acknowledged the topic’s importance by embodying it as a pillar and not a lens within the framework. Anything less would have been akin to paying ‘lip-service’ to such a critical subject. Framework lenses are better suited for recalibrating assessments for domain-specific requirements. For example, a lens for customers within the financial services sector adjusts the review for this area. Consider how aspects like security and availability were traditionally dealt with haphazardly to emphasise the significance further. We no longer have the luxury to assume that approach. There are no second chances to re-imagine habitat conservation while remaining a single planetary species.

“They have moved beyond mere virtue signals and empty promises.”

Where to from here? Consider the evolution of security’s treatment as a design factor over the past few years. It has progressed from an afterthought to a primary concern. The myriad new roles addressing cybersecurity defence reflect this shift. Tool support has evolved, and security is now tightly integrated throughout the software development lifecycle. Similar advances have emerged in other areas like availability, reliability and, more recently, cost management. One can easily presume that sustainability will follow a similar pattern.

It is inspiring that providers like AWS make concrete advances in this space. They have moved beyond mere virtue signals and empty promises. It is time for customers to follow suit and share the effort.

The duty of care remains with us all.