How to crop a photo on the server to keep the aspect ratio?

Question

linux

After uploading a photo to the server that is larger than 1000px, maybe even 4000px, you need to crop it to get a photo of different sizes - thunbnail, medium, slightly larger, etc.
The implementation language is not important. You need one that has good libraries. Or you can use Linux utilities through the command line, then any language will do.
1) How to choose the language and library? What will be the cropping algorithm? After all, you also need to consider size and orientation.
2) Or how to do it using Linux tools, or out of the box, or through popular utilities?

Answer 1

ImageMagic in any form.

Answer 2

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