warning: ignoring untrusted flake configuration setting 'extra-substituters'.
Pass '--accept-flake-config' to trust it
warning: ignoring untrusted flake configuration setting 'extra-trusted-public-keys'.
Pass '--accept-flake-config' to trust it
trace: evaluation warning: buildDepsOnly will ignore `src` when `dummySrc` is specified
these 2 paths will be fetched (0.00 MiB download, 62.63 MiB unpacked):
  /nix/store/gvansmk5pwxjyziz7v8fkzh0wilb9wcr-ucs00-pingpong-deps-1.0.0
  /nix/store/kn26ykx7ymw73d386ka058s05pc355a8-ucs00-pingpong-test-1.0.0
these 2 paths will be fetched (0.00 MiB download, 62.63 MiB unpacked):
  /nix/store/gvansmk5pwxjyziz7v8fkzh0wilb9wcr-ucs00-pingpong-deps-1.0.0
  /nix/store/kn26ykx7ymw73d386ka058s05pc355a8-ucs00-pingpong-test-1.0.0