I once had an experience where I was hired as a freelancer to work on a critical live app. At first, the task sounded simple: “We just need a small update.” But when I opened the project, I realized the codebase was far from simple. It was old, tangled, and every small change felt risky like pulling on one thread of a sweater and watching the whole thing unravel.
This reminds me of a time when I tried fixing an old piece of furniture. I thought tightening one screw would be easy, but as soon as I did, I discovered the whole frame was loose. That’s exactly how it felt working in that app: one change revealed another hidden issue.
This happened when I was asked to adjust a calculation that showed up in a report. What looked like a two-line fix turned into a journey across several files, with no comments and inconsistent logic. I felt the same way as when I tried to untangle a pair of headphones every time I pulled, the knot got worse.
So how did I deal with it without breaking the live system? Here’s what worked for me:
Put Safety Nets in Place
Before making any changes, I added tests around the existing behavior. This gave me confidence that if something broke, I’d know right away. It felt like setting up guardrails before driving down a dangerous road.
Work in small steps
Instead of trying to fix everything, I made small, safe improvements. If a function was too long, I split it into two. If a variable had a confusing name, I renamed it. These little wins kept the system stable while making the code easier to understand.
Leave it better than you found it
As a freelancer, I knew I wouldn’t always be around to explain my changes. So my personal rule was: never leave the code in a worse state. A clear comment or a small refactor might feel minor, but for the next developer, it could save hours.
Respect the legacy
It’s easy to get frustrated with old code, but I reminded myself that this system had been working for years. People depended on it every day. Legacy code may look messy, but it’s survived because it works. Respecting that helped me approach the job with patience rather than annoyance.
Looking back, that freelance job taught me a big lesson: dealing with legacy code in a live app isn’t about big rewrites or clever tricks. It’s about patience, safety, and steady improvements. You don’t bulldoze the old system you guide it into a better shape, one small step at a time.
It’s a bit like maintaining an old bridge. You can’t close it down because people still need to cross. Instead, you reinforce it piece by piece, until it’s stronger and safer than before.