this derivation will be built:
  /nix/store/mh13qckdyxmmqz4jpsi40f5iqha586h9-check-letta-code.drv
building '/nix/store/mh13qckdyxmmqz4jpsi40f5iqha586h9-check-letta-code.drv' on 'ssh-ng://customer@mac02.m.ntd.one'
building '/nix/store/mh13qckdyxmmqz4jpsi40f5iqha586h9-check-letta-code.drv'

upload niks3: ok