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5 Myths About Legacy Code You Should Stop Believing

Sylwia Laskowska on November 20, 2025

If you’ve ever opened a codebase and immediately whispered “oh no…”, this article is for you. Over the years I’ve had countless conversations with ...
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David Bruchmann

Beside learning about the strangler pattern I looked up about strangler figs, which taught me about often seen and special trees in Indonesia with the long and visible roots approaching the ground from top of another tree.

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Sylwia Laskowska

Haha yes, the real strangler figs are wild! 😄
And honestly… the analogy between them and the strangler pattern is so good that it might actually deserve its own post someday.
Those trees are both beautiful and slightly terrifying - perfect metaphor for legacy migrations!

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David Bruchmann

Fully agree!
I'd be quite interested in that article, I suspect it might make much work with many different sub-patterns perhaps.

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Sylwia Laskowska

It really depends 😄
The strangler pattern is funny that way - you can talk about it for hours with all the sub-patterns, edge cases and architectural rabbit holes… or you can explain it in a clean 3-minute version that covers 90% of what people actually need.

Maybe I should try both someday!

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Cesar Aguirre

I'd challenge #1 even further: legacy code is convoluted code nobody wants to touch, code we don't understand and want to stay away from it...and we don't need a dead language or an old version of a framework to meet that definition.

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Sylwia Laskowska

Yes, I totally agree! A friend of mine recently told me about refactoring some code that wasn’t even particularly old-it was just written with a slightly older tech stack (I think it was redux-forms) and had become the source of tons of bugs. She also pointed out that if she had started writing that module a few years earlier, she probably would have used the exact same stack…

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shemith mohanan

Really enjoyed this breakdown. Developers often blame “legacy” like it’s some cursed artifact, but you nailed it — most of the pain comes from assumptions, not the code itself.
The reminder that mismatch (not age) is the real culprit is spot on. Also loved the part about choosing the right migration strategy instead of blindly following strangler or big-bang rules.

Simple, practical, and honestly comforting for anyone inheriting messy systems. Great read.

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Sylwia Laskowska

Thank you so much - really appreciate this! 🙌
Totally agree: “legacy” gets treated like a cursed object when most of the frustration actually comes from the stories we tell about it.
Once you frame it as mismatch + normal system evolution, things suddenly feel way less scary.

Glad the migration strategy part resonated too - there’s no one-true-path, just trade-offs.
Really happy you enjoyed the read! 😊

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Ramkumar L

Rewarding Tech debt solvers is a great option so that people stop seeing it as a hurdle .. For a car to run you need to replace old parts as well as sometimes repair and give new upgraded parts . That's something part of any building process and not to be actually given the scary tag of debt .

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Sylwia Laskowska

Totally agree! Tech debt is just normal maintenance - like replacing parts in a car so it keeps running. It shouldn’t be treated as something scary or shameful.
And yes, rewarding people who tackle it is a great way to make it feel like valuable engineering work, not a burden.

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Benjamin Nguyen

hahah! It is so true

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Sylwia Laskowska

Haha right? 😄 Thanks for reading!

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Benjamin Nguyen • Edited

You are welcome! Hahah. It is :). I can't wait for your next reading!

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Aaron Rose

👍💯✨

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Amir Saleem

its very interesting to write code with full technique for learning and developing websites through update libraries also customization.

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Sylwia Laskowska

Thanks for sharing! 😄 Updating libraries and customizing code is definitely a big part of learning and growing as a developer.

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GirlCode Official

Great article!

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Sylwia Laskowska

Thank you! Glad you enjoyed it 😄

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G.O. Brents

How does a developer write code that has in mind that one day it might have to be updated and upgraded?
Or can they?

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Sylwia Laskowska

Great question! I think the honest answer is: we can try - but we can’t predict everything.
The best we can do is write code that’s clear, decoupled, and easy to change later.
Eventually every codebase will still need updates anyway, and that’s totally normal. 😄