structuredAttrs is enabled

trying https://github.com/raine/aven/archive/refs/tags/v0.1.21.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
100  3.34M   0  3.34M   0      0  4.39M      0                              0
unpacking source archive /nix/var/nix/builds/nix-34111-1806932455/download.tar.gz