Btop
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btop is a very popular system monitor application, it is the third iteration of the program which initially started as bashtop before bpytop before finally btop. It is currently written in C++.
When using btop on any system with binaries in the Nix store the processes show the full hash which can clutter the screen, there exist patches which you can apply to btop to trim the paths and improve readability. You can find one such example created by NotAShelf. For information on how to apply it to your system read Overlays#Adding_patches.