As developers, we always value interesting challenges, especially those related to sustainability and sustainable software development. However, we rarely ask ourselves during the development process whether the final product we are building is truly sustainable.
Every line of code we write, every build we upload, every test we run, everything related to data centers... everything has an impact that often goes unnoticed.
On a personal level, every time I am about to add a new line of code or upload a new build for testing, I question how efficient I am being. I may worry more than usual, but one of my principles as a developer is “prevention before cure”, so I always try to anticipate possible unforeseen events or identify weaknesses from the early stages of a project.
A few weeks ago I had the opportunity to attend Try Swift, an event where a talk was given that left a great impression on me - and never better said.
During the conference, I was able to speak personally with Noah Martin, founder of Emerge Tools, who raised an issue that I consider crucial: the cost of compilations and their impact on the environment.
Part of the content of his talk is also included in his article “The Cost of a Byte”where he addresses several key points that I would like to highlight and which are thought-provoking:
- Application size: Larger applications mean slower installation times, higher failure and uninstall rates, as well as negatively affecting runtime performance and increasing memory consumption.
- Environmental impact: although an installation file may seem insignificant, increasing the size of an app by just 1 MB can mean tons of CO₂ emissions per month when we are talking about millions of downloads.
- Cost to the user and to the planet: beyond performance, each additional byte represents a data transfer cost to the user, and contributes to the energy expenditure and environmental impact of Internet infrastructures.
In fact, the article notes that the Internet's carbon footprint is around 3 % of global emissions, a figure comparable to that of the airline industry.
Through different studies and estimates, Noah demonstrates how seemingly small decisions can be greatly amplified on a global scale, turning them into major opportunities for improvement.
You can read the full article here:
And you can also watch the full Try Swift conference talk here:
What could we do for sustainable software?
As developers, we tend to focus mainly on aspects such as the functionality or performance of our applications. However, it is worth stopping to think about their environmental impact as well.
Every decision we make-optimizing code, reducing unnecessary compilations, minimizing external dependencies, and approaching architecture reviews with efficiency in mind-can make a significant difference, not only in the user experience, but also in the sustainability of the software we create.
Actions such as:
- Avoid adding redundant code.
- Opt for really necessary and light libraries.
- Plan deployments well so as not to generate unnecessary builds and updates.
- Reduce the size of assets and optimize resources.
These are small gestures that, multiplied by millions of devices and users, have a real impact.
Final reflection
We may not be able to change the world by optimizing the size of our applications alone, but every small gesture counts, especially when our products reach millions of people.
Digital sustainability is a shared challenge, and each of us can consciously contribute.
I invite you to reflect: what small actions could we incorporate in our daily lives to build a more efficient and more respectful software for our planet?
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