Why Linters Hate Unused Imports

If you’ve been writing Python code for long, you’ve run into one of the many tools that want to clean up your files. You know the type: black, ruff, isort, flake8. Some focus on formatting, others look for deeper issues in your code, but nearly all of them seem to share one opinion: unused imports must go.

At first, this might seem a little nitpicky. After all, what's the harm in a stray import os if you're not using it? Why are these tools so eager to delete code that isn’t even doing anything?

Turns out, there are good reasons to nuke unused imports. And while it starts with clean code, the reasons don’t end there.

Unused imports are a small issue that can cause big problems in Python.

They’re Not Just Harmless

Unused imports may not break your program, but they do add clutter. Clutter that makes your code harder to read, harder to maintain, and more error-prone over time.

Think of your codebase as a kitchen. If every tool you’ve ever used is sitting on the counter, it takes longer to find what you actually need. The same goes for reading code: when someone sees import pandas as pd, they’ll expect to see some data wrangling below. If that never comes, the reader is left wondering—did you forget something? Is something broken?

This kind of noise can lead to real problems, especially in larger projects where teams depend on each other’s code being predictable and clean.

Click to read more about how isort can improve your Python.

They Can Actually Cause Bugs

Here’s where it gets more interesting. Unused imports can introduce subtle bugs in a few ways:

• Namespace collisions: Let’s say you’re importing datetime and pandas, and then later switch to using from datetime import datetime. If you forget to remove the earlier import, you could accidentally shadow one with the other.

• Outdated references: Maybe a module used to depend on a third-party package, but doesn’t anymore. The old import sticks around, and one day someone decides to remove the package from requirements.txt… boom, import error.

• Initialization side effects: Some modules execute code just by being imported. Even if you’re not using them directly, they might open sockets, create temporary files, or do other things you don’t expect. This is rare, but it happens. And when it does, it’s a nightmare to debug.

You’re Probably Not the Only One Touching This Code

Code is communication. Whether you’re working in a small team or contributing to an open-source project, you’re writing for other people just as much as you’re writing for the computer. Tools like black and ruff aren’t just enforcing style; they’re enforcing clarity.

That’s especially important in DevOps environments, where scripts and infrastructure code tend to evolve quickly. It’s easy to accumulate little bits of cruft: one-off scripts, unused dependencies, commented-out experiments. A simple unused import might be the tip of the iceberg.

Keeping your code clean helps your future self, your teammates, and your automation tools all work a little better.

Caparra Tools Can Help

At Caparra, we think great software development starts with what we call brilliance in the basics. If you and your team define and enforce engineering standards around simple tools, you all get on the same page and can focus on making more progress. Simple tools like ruff and black help enforce standards so that team members can work together with less friction, and individual developers can work on their features without getting blocked by a teammate.

Our AI-powered tools handle repetitive, error-prone tasks: things like running linters, formatting code, and enforcing consistency across a fleet of services. Instead of every developer remembering to manually run cleanup commands, Caparra tools can spot and fix these issues automatically as part of your workflow.

This doesn’t just save time; it helps teams avoid the kind of small problems that snowball into big ones. We’ve seen how these little details like a forgotten import can lead to hours of debugging or missed deploys. That’s the kind of toil we want to eliminate.

A Cleaner Codebase Is Just the Beginning

Unused imports might not seem like a big deal, but cleaning them up is about more than tidying up your main.py. It’s about keeping your codebase lean, clear, and reliable. And it’s one of many ways Caparra tools can reduce the burden of maintenance, so developers can focus on building things that matter.

Want to learn more about how Caparra can help your team automate the basics and avoid burnout? Open a free Caparra account to get access to our tools, learn more about DevOps best practices, and see what our Agent can do for you.