these 2 derivations will be built:
  /nix/store/6633aqg7jzwd4y71sxynvz87js9w8d2s-elemental_demo.zip.drv
  /nix/store/wvik87gl0vxx3qqdzwi8wbjp39ihzcf6-ue4demos-elemental_demo.drv
building '/nix/store/x7xiych8cbjsp4yv7idl5ac3r3baj7yx-elemental_demo.zip.drv'
elemental_demo.zip> 
elemental_demo.zip> trying https://ludios.org/mirror/ue4demos/elemental_demo.zip
elemental_demo.zip>   % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
elemental_demo.zip>                                  Dload  Upload   Total   Spent    Left  Speed
elemental_demo.zip> 100 1077M  100 1077M    0     0  27.6M      0  0:00:38  0:00:38 --:--:-- 25.2M
building '/nix/store/wvik87gl0vxx3qqdzwi8wbjp39ihzcf6-ue4demos-elemental_demo.drv'
ue4demos-elemental_demo> Archive:  /nix/store/c4r1naqyf9ydb1gz6mbqga7skm5nvyg3-elemental_demo.zip
ue4demos-elemental_demo>    creating: Elemental Demo/
ue4demos-elemental_demo>    creating: Elemental Demo/Elemental/
ue4demos-elemental_demo>  extracting: Elemental Demo/Elemental.png  
ue4demos-elemental_demo>    creating: Elemental Demo/Elemental/Content/
ue4demos-elemental_demo>    creating: Elemental Demo/Elemental/Content/Paks/
ue4demos-elemental_demo>   inflating: Elemental Demo/Elemental/Content/Paks/Elemental-LinuxNoEditor.pak  
ue4demos-elemental_demo>    creating: Elemental Demo/Elemental/Saved/
ue4demos-elemental_demo>    creating: Elemental Demo/Elemental/Saved/Config/
ue4demos-elemental_demo>   inflating: Elemental Demo/Elemental/Saved/Config/controller.vdf  
ue4demos-elemental_demo>    creating: Elemental Demo/Engine/
ue4demos-elemental_demo>    creating: Elemental Demo/Engine/Binaries/
ue4demos-elemental_demo>    creating: Elemental Demo/Engine/Binaries/Linux/
ue4demos-elemental_demo>   inflating: Elemental Demo/Engine/Binaries/Linux/Elemental  
ue4demos-elemental_demo>   inflating: Elemental Demo/Engine/Binaries/Linux/libicudata.so  
ue4demos-elemental_demo>   inflating: Elemental Demo/Engine/Binaries/Linux/libicui18n.so  
ue4demos-elemental_demo>   inflating: Elemental Demo/Engine/Binaries/Linux/libicuio.so  
ue4demos-elemental_demo>   inflating: Elemental Demo/Engine/Binaries/Linux/libicule.so  
ue4demos-elemental_demo>   inflating: Elemental Demo/Engine/Binaries/Linux/libiculx.so  
ue4demos-elemental_demo>   inflating: Elemental Demo/Engine/Binaries/Linux/libicutu.so  
ue4demos-elemental_demo>   inflating: Elemental Demo/Engine/Binaries/Linux/libicuuc.so  
ue4demos-elemental_demo>   inflating: Elemental Demo/Engine/Binaries/Linux/libopenal.so.1  
ue4demos-elemental_demo> Elemental Demo

upload niks3: ok