Arduino is a toy/prototyping platform that you really shouldn’t use for productive solutions (it’s got terribly bad code quality, bugs that have been open for over a decade, it’s basically unmaintained by now). 1k lines is a micro project. It’s really small. All that’s on a level where if this is just an internal solution that isn’t sold to customers it’s ok if the code is shit as long as it works. If you are actually selling it to customers or you rely on it performing a critical function, you should urgently move away from Arduino anyway.