The Server Room That Changed How I Think About Sustainability

I’ll never forget the first time I walked into Rocket Money’s old server room in 2019. The temperature hit you like a wall, it had to be close to 35°C (95°F) in there. The air conditioning was running full blast, 24/7, just to keep those servers from melting down.

That’s when it clicked for me: every line of code I write, every database query that runs, every user interaction, it all translates to actual electricity being consumed somewhere. Real heat being generated. Real environmental impact.

Up until that moment, sustainability was kind of an abstract concept for me. Sure, I recycled and tried to be mindful, but software felt clean, somehow. Digital. Disconnected from the physical world.

Standing in that furnace of a server room, listening to the constant hum of cooling fans, I realized how wrong I was.

The Numbers Game

Here’s something that’ll surprise you: the tech industry is responsible for about 4% of global carbon emissions. That’s roughly the same as the airline industry. And it’s growing fast.

Most of that comes from data centers. Every time someone uploads a photo to Instagram, streams a Netflix show, or backs up their phone to the cloud, there’s a physical server somewhere doing work. And that work requires energy.

A lot of that energy gets wasted. I’ve seen applications that make hundreds of unnecessary database calls because nobody thought to optimize them. Code that runs complex calculations every time instead of caching results. Servers sitting at 5% utilization because it was easier than right-sizing them.

What We Started Doing Differently

After that server room wake-up call, I became a bit obsessed with writing more efficient code. Not just for performance reasons, but because inefficient code literally burns more fuel somewhere.

At Toki Labs, we’ve started looking at energy efficiency as a design constraint, just like security or scalability. Some examples:

Database optimization: We had one client whose dashboard was making 200+ queries to load a single page. Took us two days to refactor it down to 5 queries. Same functionality, 40x less server work.

Smart caching: Instead of regenerating reports every time someone views them, we cache them and only update when the underlying data changes. Sounds obvious, but you’d be amazed how many applications don’t do this.

Right-sizing infrastructure: Why run a server that can handle 1000 concurrent users when you typically have 50? Cloud services make it easy to scale up when needed and scale down when you don’t.

The Bigger Picture

But here’s what I’ve learned: individual efficiency improvements, while important, aren’t enough. The real change happens when you start thinking about sustainability from the architecture level.

Take our work with Cleanify (a startup I worked with before Toki Labs). Instead of building separate mobile and web apps that would require different backend services, we designed a single API that could serve both. Less code to maintain, fewer servers to run, lower energy footprint.

Or consider how we approach microservices. Yes, they’re great for scalability and team autonomy, but every microservice needs its own infrastructure. Sometimes a well-designed monolith is actually the more sustainable choice.

The Real Challenge

The hardest part isn’t the technical stuff, it’s changing how we think about trade-offs.

We’re used to optimizing for speed of development, or user experience, or cost. Adding environmental impact to that equation makes decisions more complex. Sometimes the greenest solution isn’t the cheapest or the fastest to build.

But I’ve found that constraints often lead to better solutions. When you have to think about energy efficiency, you end up writing cleaner, more purposeful code. When you consider the environmental cost of data storage, you become more thoughtful about what you actually need to keep.

What’s Next

I’m not going to pretend that one software consultancy is going to solve climate change. But I do think we have a responsibility to understand the impact of what we build and try to minimize it where we can.

Maybe that means choosing a cloud provider that runs on renewable energy. Or designing systems that gracefully degrade instead of crashing and burning CPU cycles. Or just thinking twice before adding that cool but unnecessary animation.

Small changes, sure. But when you multiply them across millions of applications and billions of users, they start to add up.

Plus, in my experience, sustainable code is usually better code anyway. More efficient, more maintainable, more thoughtful about resources. Win-win.

The server room at Rocket Money has since been upgraded with better cooling and more efficient hardware. But I still think about it sometimes when I’m architecting a new system. It’s a good reminder that everything we build in the digital world has a footprint in the physical one.

The question is: what kind of footprint do we want to leave?