Architectural decisions have some of the largest potential influences on software carbon intensity. They are also some of the most fundamental choices and hardest to back out of at a later point.
These decisions significantly affect the amount of hardware you use, how efficiently you utilise that hardware, and the amount of data you store or send over networks when operating software.
To ensure that you can make decisions with energy use and emissions in mind, architects must learn about sustainability concepts and take the time to understand how they can apply them to their designs.
As discussed, the industry is early in the green software development journey. While green principles are essential for any architect, there is limited implementation information about good patterns and practices.
Given this, architects will need to put effort into assessing the potential emissions impact of different options. You may need to undertake spike work where differences are not evident on paper. You can use the eight green principles to help support this process, as well as the three categories of actions that can reduce emissions, as defined by the Green Software Foundation:
Taking these into account will support greener decision making. But it’s an inexact science when the scale of emissions resulting from a decision is often difficult to quantify, especially when software is not live and measurable.
To create a green architecture culture, you should include references to sustainability motivations, assumptions, and implications in your key design decision (KDD) or architecture decision record (ADR) templates – prompting architects to include these aspects as part of their decision making.