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Posted 12 days ago · 43,294 reads

Legacy code is called legacy for a reason. It works. It's been tested in production. It's often the most reliable code in your system, even if it doesn't follow modern conventions.

Readability is not about clever code or terse syntax. It's about making the intent of the code obvious to the next person who reads it—which might be you, six months later, having forgotten everything.

The best code is often the code you don't write.

Legacy code is called legacy for a reason. It works. It's been tested in production. It's often the most reliable code in your system, even if it doesn't follow modern conventions.

The most important insight I've had in the last few years is that constraints are a feature, not a bug. When you have unlimited resources, you can solve any problem in a hundred different ways. When you have constraints—limited memory, limited time, limited developers—you're forced to think more clearly.

The most important insight I've had in the last few years is that constraints are a feature, not a bug. When you have unlimited resources, you can solve any problem in a hundred different ways. When you have constraints—limited memory, limited time, limited developers—you're forced to think more clearly.

Legacy code is called legacy for a reason. It works. It's been tested in production. It's often the most reliable code in your system, even if it doesn't follow modern conventions.

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APIs are contracts. Once you publish one, changing it becomes expensive for everyone who depends on it. The cost of breaking changes compounds over time, which is why the boring, conservative choice is usually the right one.

Systems thinking matters.

Type systems don't prevent bugs—they just catch certain categories of bugs earlier. The real benefit is the documentation they provide about what a function is supposed to do.

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