Base rules: a function should do only one thing, use descriptive variable names that make sense, document your code (explain WHY the code is there, not WHAT it does).
Write your code so it can easily be expanded and refactored. Loosely coupled modules come to mind. You could use a boolean for a function parameter, but maybe a string/enum might be better if you foresee a binary parameter won't be enough in the near future.
Don't try to be "smart" by overengineering the solution. This often leads to pointless abstractions for edge cases that may never happen. Premature optimization is a cardinal sin. "You Aren't Gonna Need It" (YAGNI)
The bigger the project/feature you're building, the more upfront design you should do. If you intend to maintain the project for a very long time, spending some time on architecture design is worth it. If it is just a quick proof-of-concept kinda thing, why bother?
An app that is never shipped does not exist. You can spend ages writing beautiful code, but your users won't care how the app looks on the inside. I don't mean you should rush writing code and take shortcuts all the time. At some point your code is just "good enough".
Sometimes you create a suboptimal implementation and decide to take on the technical debt (probably because of a deadline), while the software works as intended. If you don't intend on expanding the software, why would you touch the code again? Maybe you can leave it as is. Sometimes, a change in requirements can make the tech debt go away and the problem basically solved itself!
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Sometimes you create a suboptimal implementation and decide to take on the technical debt (probably because of a deadline), while the software works as intended. If you don't intend on expanding the software, why would you touch the code again? Maybe you can leave it as is. Sometimes, a change in requirements can make the tech debt go away and the problem basically solved itself!