structuredAttrs is enabled

trying https://github.com/activeing123/mcptoon/archive/refs/tags/v0.6.1.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  1.10M   0  1.10M   0      0  1.56M      0                              0
100  1.10M   0  1.10M   0      0  1.56M      0                              0
100  1.10M   0  1.10M   0      0  1.56M      0                              0
unpacking source archive /nix/var/nix/builds/nix-902870-1367943202/download.tar.gz