these 20 derivations will be built:
  /nix/store/fmavrpcncfiyjz7dx9y94n2yl841i2yl-unit-postgresql.service.drv
  /nix/store/qf2mp1x7az3vnlixwraaxqpab7v0zj4g-system-units.drv
  /nix/store/4yjvfksd7vap7rcjwbsyv2w6bjghw2fk-etc.drv
  /nix/store/g360b484zw0sw12wbcn41g0pmqrvznrb-activate.drv
  /nix/store/13dlay2v7vgqnrz8fpz1dmxwbms48jb7-nixos-system-server-test.drv
  /nix/store/pv6lj32c3vq1pq9d97wajapkf7ddfsvj-unit-postgresql.service.drv
  /nix/store/mfz61agjbs98ijqlpb2fmbw9121a7n8x-system-units.drv
  /nix/store/2nf8hhf5p3sq2hll16q0zyarbg89bdia-etc.drv
  /nix/store/n5rxyqwamj3wyv3x44ijqnqbmxsi2ysk-unit-postgresql.service.drv
  /nix/store/52lg2z63halh259z7130l6m2all0vbkn-system-units.drv
  /nix/store/jxyrda1vvggcx2hbx3ilx072dldvj378-etc.drv
  /nix/store/1r8034wwr93y9sf42b32qbr0zkh58av6-activate.drv
  /nix/store/dfq5z5676wprvaq0axps05x2377xyln0-nixos-system-server-test.drv
  /nix/store/fd09axj8nbmahxmgw6mmanxdajzc778m-activate.drv
  /nix/store/y5bhy0xrmpd2vgmabz7dsp5mf5rvixgk-nixos-system-server-test.drv
  /nix/store/vfvynp4bdp0hflm0im0ny3zvvkra6lqm-closure-info.drv
  /nix/store/a4sk8j0lrkg6bpd68k3jdhsvxhbnmb5j-run-nixos-vm.drv
  /nix/store/hnix4pimnq00ahv1jx1g76v913wrjsxv-nixos-vm.drv
  /nix/store/1d5b4yaqsrya9ba3zy8zf0f2ff82bcb3-nixos-test-driver-pgroonga.drv
  /nix/store/ax0j1688k7apasn87pnny02hqw7fyhpf-vm-test-run-pgroonga.drv