Security Software Development Portfolio Projects

I'm looking to expand my portfolio as a cybersecurity software developer. I had some ideas for projects.

I'm curious if anyone has built these before and can suggest whether to avoid particular projects as a solo dev or can recommend ones I haven't considered. If you've built one and have a repo you can share, it would be great to see how others go about this and what language/libraries I should use for which projects to reduce challenges.

I already …

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