Why Software Engineers Prefer Clean Code

“Forget code quality, just move fast”. Never think or act like this as a SWE. It can ruin your whole career. You see, poor code isn’t speed. It’s a liability. Here’s what happens when you rush and cut corners: • 𝗖𝗼𝗱𝗲 𝗥𝗲𝘃𝗶𝗲𝘄𝘀 𝗗𝗿𝗮𝗴 𝗢𝗻: If your PR is messy, reviewers will take forever to understand it or miss bugs entirely. That’s not moving fast. That’s creating bottlenecks. • 𝗣𝗿𝗼𝗱𝘂𝗰𝘁𝗶𝗼𝗻 𝗕𝗿𝗲𝗮𝗸𝘀 𝗙𝗿𝗲𝗾𝘂𝗲𝗻𝘁𝗹𝘆: Quick fixes become time bombs. They might pass tests today, but tomorrow, they’ll blow up in production, leading to urgent firefighting and angry customers. • 𝗙𝘂𝘁𝘂𝗿𝗲 𝗖𝗵𝗮𝗻𝗴𝗲𝘀 𝗔𝗿𝗲 𝗮 𝗡𝗶𝗴𝗵𝘁𝗺𝗮𝗿𝗲: When you write bad code, the next time someone (maybe even future you) touches it, it’s hours of frustration just to figure out what’s going on. Now, let’s flip it. Writing high-quality code might take a bit longer upfront, but here’s what you get: • 𝗙𝗮𝘀𝘁 𝗥𝗲𝘃𝗶𝗲𝘄𝘀: Clean, readable code gets approved quicker because teammates actually understand it. • 𝗣𝗿𝗼𝗱𝘂𝗰𝘁𝗶𝗼𝗻 𝗦𝘁𝗮𝗯𝗶𝗹𝗶𝘁𝘆: Well-written code rarely breaks, meaning you’re not pulled into emergencies every other day. • 𝗘𝗮𝘀𝘆 𝘁𝗼 𝗕𝘂𝗶𝗹𝗱 𝗢𝗻: Good code is like a solid foundation: adding new features becomes quick and painless. Example:  Imagine you’re building a feature with hacky code to “save time.” Now it’s live, and the next week, your manager asks you to add a small tweak. Suddenly, that tweak turns into a three-day refactor because you didn’t plan the structure properly. What you thought was fast actually cost you more time and stress. As a good software engineer, your goal isn’t just to ship code fast but to write code that’s easy for your team to maintain and extend. You’re not just building for today; you’re building for tomorrow too.

I have seen more systems struggling because of wrong code than slower ones. The fact remains, most engineers optimise too early. About 8 years ago, my principal engineer once told me: Performance is almost always the last thing you should be thinking about. As an SDE-2, this did not make sense :) After a few follow-ups, I understood why he meant that. The order that actually matters is this. First, is the code correct? Does it do what it is supposed to do? Second, can someone maintain it six months from now without wanting to quit? Third, is it fast to read and write? Only after all three does performance even enter the conversation. The reason this order exists is simple. A fast, unmaintainable codebase is a liability. A performant-but-wrong system is worse than a slow, correct one. You cannot optimise your way out of a bug. Now, this is not universally true. Databases, high-frequency trading systems, and real-time embedded software are domains where performance is a first-class concern from day one. But those are the exceptions, not the default assumption you should bring to every PR. What is certainly true is that for most codebases, premature optimisation adds complexity, reduces readability, and solves a problem that does not exist yet. So, write correct code first. Then clean it. Then, only if the profiler gives you a reason, make it fast.

"Clean" code leads to horrible performance! Many programming "best practices" taught today are performance disasters waiting to happen. That’s according to a video and blog post by Casey Muratori a couple of years ago. He manages to be both right and wrong at the same time. In the video he demonstrates that the “clean” code example he’s taken from a text book is much slower than his code that ignores the clean code rules. If you’ve been around programming as long as he, or I have, that won’t surprise you. The abstractions that are promoted by clean code have a cost, no matter how hard the designers of programming languages and compilers work to minimise the cost. So yes, clean code is going to be slower in terms of raw computational performance. Where he’s wrong is thinking that computational performance always matters. For many software systems the CPU is largely idle. The system is sat waiting for something to happen so it can respond. That’s true whether its the accounting software your bookkeeper uses or the Amazon website, even though the Amazon website no doubt has a lot of traffic. Both are going to be IO bound not CPU bound. For many of these systems, it’s better to optimise for readable, maintainable code than performance. CPU time is cheaper than software engineer time or the cost of errors. If that’s what your team does and clean code helps you deliver quickly, then go with clean code. At the same time, please be careful not to overdo the “clean” code dogma which can make the code just as hard to follow. Focus on making it simple, clear and readable for your team. If you’re writing software for games, high-frequency trading or anything else where performance matters, where there is value in shaving nanoseconds off an operation, then the cost of developer time is often much less that the cost of not hitting a performance goal, so it makes sense to optimise for performance! The trouble with the whole clean code versus performance debate is that they’re two extremes and most of us work somewhere on the spectrum between them. So don’t blindly follow advice to write clean code and don’t blindly follow advice not to. Work out what you need to optimise for in your context and optimise for it! Note that the context includes the skillset and experience of your software engineers too.

I once spent days hunting a bug that existed in 7 different places in our codebase. Every single one was a copy-paste of the same function. That week taught me more about code quality than any course I'd taken. It came down to 4 principles. Simple ones. Ones most developers know and few consistently follow. 𝗗𝗥𝗬: 𝗗𝗼𝗻'𝘁 𝗥𝗲𝗽𝗲𝗮𝘁 𝗬𝗼𝘂𝗿𝘀𝗲𝗹𝗳. Write logic once. The moment you copy-paste, you're creating future pain. One bug becomes seven bugs. One fix becomes seven fixes you'll probably miss. 𝗬𝗔𝗚𝗡𝗜: 𝗬𝗼𝘂 𝗔𝗶𝗻'𝘁 𝗚𝗼𝗻𝗻𝗮 𝗡𝗲𝗲𝗱 𝗜𝘁. Don't build for the future you're imagining. I wasted months early in my career shipping features nobody asked for. Write what's needed now, design so it's easy to change later. 𝗞𝗜𝗦𝗦: 𝗞𝗲𝗲𝗽 𝗜𝘁 𝗦𝗶𝗺𝗽𝗹𝗲, 𝗦𝘁𝘂𝗽𝗶𝗱. If you can't explain how your code works to a colleague in 30 seconds, it's too complex. Simple code breaks less and gets fixed faster. 𝗦𝗜𝗡𝗘: 𝗦𝗶𝗺𝗽𝗹𝗲 𝗜𝘀 𝗡𝗼𝘁 𝗘𝗮𝘀𝘆. This is the one people skip. A 500-line function is easy to write. A clean, reusable 20-line function takes real discipline. Simplicity is the hardest thing to build. Ignore these four long enough and every feature takes longer, every bug takes longer, and your best engineers leave because the codebase has become a nightmare. Simple code isn't lazy code. It's the most disciplined work in engineering. Which of these 4 do you find hardest to apply consistently — and can you share one real example where ignoring it cost you time or sanity?

Every developer, at some point, falls into the same trap. You want to prove you’re smart. You want your peers to look at your code and think, “Wow, this person really knows what they’re doing.” So you add abstraction layers no one asked for. You sprinkle in clever design patterns because they make you feel sophisticated. And before long, what started as a clean, understandable project becomes a maze that even you struggle to navigate six months later. That’s the hidden cost of cleverness. That’s why the KISS principle isn’t just a cute acronym. It’s a survival strategy. “Keep It Simple and Smart” means designing systems that anyone on your team can pick up, reason about, and improve without first decoding your genius. Because when you minimize complexity: - Onboarding becomes easier. - Bugs decrease. - Maintenance stops feeling like archaeology. I often tell clients and engineers in my workshops: If an entry-level developer can’t understand your design, it’s too clever for its own good. As Brian W. Kernighan famously said: “Debugging is twice as hard as writing the code in the first place. Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it.” So the next time you’re tempted to overengineer, remember: Anyone can make something complicated. It takes real mastery to make it simple.

Clean code isn't just about readability —it's about creating maintainable, scalable solutions that stand the test of time. When we prioritize readability, simplicity, and thoughtful architecture, we're not just making our lives easier; we're creating value for our teams and organizations. A few principles that have made the most significant difference in my work over years: • Meaningful naming that reveals intent • Functions that do one thing exceptionally well • Tests that serve as documentation and safety nets • Consistent formatting that reduces cognitive load The greatest insight I've gained is that clean code is fundamentally an act of communication—with future developers, our teammates, and even our future selves. The time invested upfront pays dividends during maintenance, debugging, and onboarding. What clean code practices have transformed your development experience? I'd love to hear about the principles that guide your work. Image Credit - Keivan Damirchi

6+ years in software engineering, and I still fall for this ONE coding mistake. Every. Single. Time. ⏰ I overcomplicate things. Early in my career, I thought: ✔ More code = better solution ✔ Complex logic = impressive skills ✔ Clever hacks = smart engineering I was wrong. The best engineers I’ve worked with all follow one simple rule: Keep it simple. Here’s what I’ve learned the hard way: 1️⃣ Readable code > Clever code If your code needs an explanation every time someone reads it, you’ve already lost. 2️⃣ Premature optimization is a trap Make it work first, then make it fast. Not the other way around. 3️⃣ The simplest solution is often the best If your solution feels unnecessarily complex, take a step back - it probably is. 4️⃣ Future-you will thank present-you for writing clean code Your code isn’t just for you. It’s for your team, your future self, and anyone who maintains it. 6+ years in, and I still remind myself daily: Write less, do more. 👇 What’s a coding mistake you still fall for? ♻️ Find it insightful? Consider reposting for your network!