this derivation will be built:
  /nix/store/g91sasgf5cyg16vva0gbpyyiibhaxiq7-hax-0.4.0.drv
this path will be fetched (7.7 KiB download, 30.5 KiB unpacked):
  /nix/store/lfws0wmi7bgvdy09gdrc9w10m0zkqi9i-jansson-2.15.0-dev