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Waruni Manike
Waruni Manike

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The Hidden Dockerfile Mistakes That Waste Hours (Thinking of Building a Tool for This)

Developers love to pretend their Dockerfiles are perfect until a build takes eight minutes and the image balloons bigger than a AAA game update. Most of the time, the cause is embarrassingly simple stuff: missing version pins, unnecessary layers, or copying half the universe into the image.

Example mistakes I keep seeing:

"RUN apt-get install python
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No version pin. Enjoy the surprise upgrades later.

COPY . .

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Congrats, you just shoved your entire repo and node_modules into the image because why not.

RUN pip install --upgrade pip
RUN pip install -r requirements.txt
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Two separate layers doing what one should handle.

I’m exploring a small, focused tool that analyzes Dockerfiles and built images to catch these issues quickly. No AI circus, just rule checks and clear suggestions.

I’m curious how common this pain actually is.
Would something like this be useful in your workflow, or do you already rely on another tool?

Feel free to comment your thoughts or examples of Dockerfile mistakes you’ve faced

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