Sooner or later, most teams working on long-standing products hit the same wall: “Do we try to clean up what we have, or just rebuild it from the ground up?“. Even well-designed apps eventually start to feel heavy. Things slow down, libraries get out of date, parts of the code turn into black boxes no one wants to deal with. It’s not necessarily anyone’s fault — just the result of growth, deadlines, and years of quick fixes.
And here’s the tricky part: choosing between refactoring and rebuilding isn’t only about tech. It’s a bigger, strategic decision that affects time, cost, team morale, and user experience. There’s no silver bullet, but there are patterns — and learning from them can help you make a smarter call when the moment comes.
Spoiler: there’s no universal answer. But there are tradeoffs. And if you’ve been through it (or you’re in the middle of it now), you know it’s as much about people and product as it is about code.
Refactoring: Clean it up, bit by bit
Refactoring means you keep the current system, but gradually improve how it works under the hood. You change how the code is structured without changing what it does. Think of it like cleaning your kitchen — you’re not building a new one, but you are pulling out the drawers, getting rid of junk, and maybe fixing a few hinges.
When refactoring makes sense:
The product still works — it’s just messy inside
The core architecture still makes sense
Bugs are manageable, but tech debt is slowing you down
The team understands the logic, even if it’s ugly
You don’t want to pause feature development for too long
The product is live and users are happy (or at least not screaming 🙂)
Refactoring is safer. You don’t throw away everything and hope the rewrite catches up. Instead, you work in slices: untangling logic, isolating components, adding tests. You might be stuck with some old architecture. But you can keep shipping. You’re not gambling the whole product on one big rewrite.
Example: Facebook did this. Instead of rewriting everything, they created tools like HHVM and Hack to optimize their existing PHP codebase. They invested in tooling to refactor and transform code at scale. This allowed Facebook to maintain continuity, support billions of users, and evolve their platform — all without starting over.
Rebuilding: Burn it down and start fresh
Rebuilding means throwing out the old system (or most of it) and building something new from the ground up. Clean architecture. Modern stack. No legacy hacks. Tempting, right?
When rebuilding makes sense:
The current code is beyond saving
Supporting the old code is more expensive than replacing it
It’s hard to onboard new developers
You’re spending more time patching than building
There’s no proper test coverage, and every update feels risky
The product has changed significantly since it was first built
But rewrites are risky. You’ll need to reimplement a lot of hidden behavior. You’ll hit edge cases you forgot existed. You’ll have to maintain the old app while building the new one. And if you underestimate the effort, the whole thing can drag on for months — or worse, get scrapped halfway.
Example: Basecamp went this route. The team rebuilt their app multiple times (Basecamp 2, Basecamp 3, Basecamp 4), each version designed from scratch and reflected new ideas, technologies, and product goals. They had a clear product philosophy and weren’t afraid to start over. And since they kept the team small and the scope tight, it worked. The main reasons for their specific “starts from scratch” in different versions were: outdated code, large technical debt, desire for radical changes to UX, problems with scaling.
In their book Rework, 37signals (now Basecamp) argues that starting from scratch is often a more effective approach than trying to retrofit an existing system. Personally, these complete rewrites often demonstrate why minimalism in product design matters: building fewer but higher-quality features simplifies maintenance and reduces the need for radical rebuilds.
The Hybrid Path
In real life, many teams don’t fully refactor or rebuild. They do both.
You isolate a broken piece of the system, rewrite it properly, and integrate it back. Or you slowly extract parts into microservices. Or you build a new UI while keeping the backend. This hybrid approach gives you the best of both worlds: less risk than a full rewrite, and better code than just refactoring.
Example: Gmail evolved this way. Google gradually updated parts of Gmail (GWT → Closure → Angular) — while the core product kept running. At one point, users could even switch between old and new layouts. The key reasons for choosing a hybrid approach over a full rewrite of Gmail were: the enormous scale of the codebase and user base, the risks of “outages”, incremental improvements were cheaper than taking the service offline for an extended period.
So… What should You do?
There’s no checklist, but here are a few questions that can help:
What’s actually broken? The tech, the product, or the team?
Can we keep the lights on while we clean things up?
Do we understand the old system well enough to rewrite it?
What happens if we try and fail?
Do we have the people to pull this off?
And maybe the most important one: Are we solving a real problem, or just chasing something shiny?
Final Thoughts
Refactoring is boring, but safer. Rebuilding is exciting, but risky. Somewhere in between is usually where most teams land. Just be honest about your goals, and your limits. At the end of the day, your users don’t care how beautiful the code is. They just want the app to work. So whether you’re rewriting or just cleaning house — make sure you’re fixing the things that matter.
And from own experience at IT-Dimension, we’d like to add: Don’t chase feature quantity or excessive product scale. Focus on quality first. Build less, but build it better. This approach makes technical maintenance easier and reduces the risk of hitting a wall where a full rebuild becomes the only solution.
Contact us for a product consultation or audit—we’ll help you make efficient, future-proof decisions.
