structuredAttrs is enabled

trying https://github.com/quietpublish/mardi-gras/archive/refs/tags/v0.34.0.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  8.32M   0  8.32M   0      0  9.86M      0                              0
100  8.32M   0  8.32M   0      0  9.85M      0                              0
100  8.32M   0  8.32M   0      0  9.85M      0                              0
unpacking source archive /nix/var/nix/builds/nix-50606-122395162/download.tar.gz