Three Key Design Decisions Behind a Small Python CLI File-Sorting Tool

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A developer building a Python CLI tool that scans and sorts files into folders by type documented three design choices made during development. They chose pathlib over os.path because it offers explicit, typed methods like .suffix and .suffixes, making compound extensions such as .tar.gz easier to handle correctly. A dry-run mode was implemented so that file classification logic runs identically in both preview and live modes, with only the final move step differing. File-type mappings were stored in a dictionary rather than an if/elif chain, separating data from logic and making it easier to extend or move to an external config file. The author noted that the value lay not in the novelty of each choice, but in the habit of questioning the default approach before writing code that works short-term but carries hidden long-term costs.

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