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Posted 10 days ago · 39,559 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.

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.

Your future self will thank you.

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.

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.

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.

I've noticed that the best technical decisions come from understanding not just what works, but why it works. The deeper your intuition about a system, the better your architectural choices become.

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

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.