Help with a derivation/package

I have been trying to add Jebtrains Toolbox as a package to Nix and here is my copy-pasta attempt https://github.com/amanjeev/nixpkgs/blob/amanjeev/jetbrains-toolbox/pkgs/applications/editors/jetbrains/toolbox/default.nix

The issue I am facing is that it installs ok (using nix-env -f . -iA jetbrains-toolbox);
but running jetbrains-toolbox gives error

dlopen(): error loading libfuse.so.2

AppImages require FUSE to run. 
You might still be able to extract the contents of this AppImage 
if you run it with the --appimage-extract option. 
See https://github.com/AppImage/AppImageKit/wiki/FUSE 
for more information

When I add fuse as a dependency then it gives error

This doesn't look like a squashfs image.

Cannot mount AppImage, please check your FUSE setup.
You might still be able to extract the contents of this AppImage 
if you run it with the --appimage-extract option. 
See https://github.com/AppImage/AppImageKit/wiki/FUSE 
for more information
open dir error: No such file or directory

Any help on what I am doing wrong will be great! Thank you!