these 19 derivations will be built:
  /nix/store/13if0hygir0fcjcbfkjkmm8gjk8w11wa-unit-niks3.service.drv
  /nix/store/jhqjl20c8cr9sxz16nk5ajm5ai5kysbi-system-path.drv
  /nix/store/clv3qcnykssvr2z89z3l1173dcqlmy4l-dbus-1.drv
  /nix/store/wmc1sbnj1xwil7lraihcdh0nihs2hxgx-X-Restart-Triggers-dbus-broker.drv
  /nix/store/lw8qksq8565yl6bi527n5x4ay35nc3fh-unit-dbus-broker.service.drv
  /nix/store/3jpryzd6rn6r916rqxbcpz4rxy6cn35f-user-units.drv
  /nix/store/k8mmnhq7fvj1bn7g7674cdd9irbrwy3q-unit-niks3-gc.service.drv
  /nix/store/qxlm4m1kq7qhc5hjmz4kyrl7zl55gj8n-unit-dbus-broker.service.drv
  /nix/store/mwyaxsw5cnynyzgf0ar3r57v9m9fi7w5-system-units.drv
  /nix/store/qyl1fx7xv1n58cq283y6mclpdfv93pln-etc.drv
  /nix/store/4ljra1bxxj0b4n7xpp7dnhqlrjdbz73c-activate.drv
  /nix/store/a64gz8lasxcp9pn0g95b0hy050v8cdal-nixos-system-server-test.drv
  /nix/store/xpyx4v95iildq1z7w0mwszhlg2x7j7z7-closure-info.drv
  /nix/store/sfsxr5kz1yi1r36r1ffl350c0fm1kapr-run-nixos-vm.drv
  /nix/store/js23hwp5m9gj6p7yy2aavdz2kwssm5xz-nixos-vm.drv
  /nix/store/zcy9yvmkwj56bn7d64dndn05mnj8ha5m-test-script.drv
  /nix/store/a43g5n4f7nc86d32hq0hsblw8a7yngin-driverConfiguration.json.drv
  /nix/store/dai9nk1v6qp8s6ijr4vbawhc201qgyx2-nixos-test-driver-nixos-test-external-signer.drv
  /nix/store/582n7idc6zsxyd6mkxgj1n2ngia46y7z-vm-test-run-nixos-test-external-signer.drv
Failed to find a machine for remote build!
derivation: 582n7idc6zsxyd6mkxgj1n2ngia46y7z-vm-test-run-nixos-test-external-signer.drv
required (system, features): (aarch64-linux, [kvm, nixos-test])
1 available machines:
(systems, maxjobs, supportedFeatures, mandatoryFeatures)
([aarch64-darwin, x86_64-darwin], 8, [big-parallel, recursive-nix], [])