Performance isn't a luxury

Source: Dev.to

Why performance matters

When we talk about performance in software, most people think of speed — how fast an API responds, how quickly a page loads, how many requests a server can handle. But performance is more than a technical metric. It’s about efficiency, sustainability, and ultimately, craftsmanship.

Every line of code we write consumes CPU cycles somewhere — on your laptop, in the cloud, or on billions of phones around the world. Those cycles aren’t free; they cost time, energy, and money.

The impact of inefficiency

A single inefficient function may seem harmless, but when it runs across millions of requests per day, that “harmless” inefficiency becomes a large‑scale energy drain.

Consider this: if you save even 10 ms in a function that’s called a million times daily, you’re saving nearly three hours of global CPU time every single day. Multiply that by thousands of apps and services — and the collective waste becomes enormous.

Performance and readability

Writing performant code isn’t just about “premature optimization.” It’s about responsibility — respecting compute resources, the environment, and users’ time.

There’s a common misconception that performant code is hard to read or maintain. In reality, it’s the opposite. When you focus on performance, you naturally start simplifying logic: fewer database calls, smaller loops, leaner abstractions.

Good performance often emerges from clarity — not from complex tricks. A well‑thought‑out query, a well‑batched background job, or a single source of truth for data — these are small, readable, high‑impact decisions that make software better for everyone.

Scale of impact

Most engineers today aren’t building operating systems or graphics engines. We’re building web apps, internal tools, SaaS platforms — applications. That doesn’t mean performance is someone else’s problem. The scale of application development today means that even small gains made by everyday developers can lead to massive global improvements.

If millions of developers write slightly more efficient code, the compounded result is faster web experiences, reduced energy usage, and lower carbon impact from data centers. Small local wins turn into global progress.

Frameworks and languages

Writing performant code doesn’t mean abandoning the frameworks and languages we love. You can write efficient code in Ruby, Python, JavaScript, or Go — as long as you respect how your tools work and make intentional choices.

In the Ruby ecosystem, for example, you can achieve excellent performance by embracing Rails with Hotwire. Hotwire allows you to build dynamic, reactive front‑ends without heavy JavaScript frameworks, keeping apps fast, simple, and light on resources — both on the client and the server. You stay productive as a developer, users get snappy interactions, and the world saves a few trillion unnecessary CPU cycles.

Conclusion

Performance isn’t just a technical virtue. It’s a mindset. The next time you optimize a query, refactor a loop, or shave off a few milliseconds — remember: you’re not just speeding up your app. You’re participating in a quiet, global movement towards better, leaner, and more sustainable computing.

Performance is care. It’s empathy translated into code. Write like every cycle matters — because it does.