structuredAttrs is enabled

trying https://github.com/activeing123/mcptoon/archive/refs/tags/v0.8.19.tar.gz
  % Total    % Received % Xferd  Average Speed  Time    Time    Time   Current
                                 Dload  Upload  Total   Spent   Left   Speed

  0      0   0      0   0      0      0      0                              0
  0      0   0      0   0      0      0      0                              0
  0      0   0      0   0      0      0      0                              0

  0      0   0      0   0      0      0      0                              0
100 13.51M   0 13.51M   0      0  9.68M      0           00:01         13.51M
100 13.76M   0 13.76M   0      0  9.83M      0           00:01         13.51M
100 13.76M   0 13.76M   0      0  9.83M      0           00:01         13.51M
100 13.76M   0 13.76M   0      0  9.83M      0           00:01         13.51M
unpacking source archive /nix/var/nix/builds/nix-2873881-1218687904/download.tar.gz