• built on NixOS

• The tests defined in passthru.tests, if any, passed

• 0 of 0 passed binary check by having a zero exit code.

• 0 of 0 passed binary check by having the new version present in output.

• found 3.4.9 with grep in /nix/store/jgwn1rjv2klqvpgdzhh29nc46db6rhlk-postfix-3.4.9

• directory tree listing: https://gist.github.com/f21cba40e5b5b0f964b9c9a8c8edff3e

• du listing: https://gist.github.com/e60a87f87ad6a72b1c5f9585f1665792

23 total rebuild path(s)

6 package rebuild(s)

6 x86_64-linux rebuild(s)
6 i686-linux rebuild(s)
5 x86_64-darwin rebuild(s)
6 aarch64-linux rebuild(s)

First fifty rebuilds by attrpath
mailman
postfix
python37Packages.mailman
python37Packages.mailman-hyperkitty
python38Packages.mailman
python38Packages.mailman-hyperkitty

Either download from Cachix:

nix-store -r /nix/store/jgwn1rjv2klqvpgdzhh29nc46db6rhlk-postfix-3.4.9 \
  --option binary-caches 'https://cache.nixos.org/ https://r-ryantm.cachix.org/' \
  --option trusted-public-keys '
  r-ryantm.cachix.org-1:gkUbLkouDAyvBdpBX0JOdIiD2/DP1ldF3Z3Y6Gqcc4c=
  cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY=
  '

(r-ryantm's Cachix cache is only trusted for this store-path realization.)
For the Cachix download to work, your user must be in the trusted-users list or you can use sudo since root is effectively trusted.

Or, build yourself:

nix-build -A postfix https://github.com/r-ryantm/nixpkgs/archive/dc1a84cdcdaf2004c012fbf3b9a2fa90376227ee.tar.gz

After you've downloaded or built it, look at the files and if there are any, run the binaries:

ls -la /nix/store/jgwn1rjv2klqvpgdzhh29nc46db6rhlk-postfix-3.4.9
ls -la /nix/store/jgwn1rjv2klqvpgdzhh29nc46db6rhlk-postfix-3.4.9/bin