gistfile1.txt

bash-3.2$ cat test.nix
{ pkgs ? import <nixpkgs> {} }:
with pkgs;

mkShell {
  buildInputs = [
    sphinxsearch
  ];

  env = buildEnv {
    name = "unprefixed-sphinx";
    paths = [ sphinxsearch ];
    postBuild = "ls -la $out; ln -s $out/bin/sphinxsearch-searchd $out/bin/searchd";
  };
}

bash-3.2$ nix-shell test.nix
these derivations will be built:
  /nix/store/ii2rprxx8gc9wwi4f15k1miaxa2lay0z-unprefixed-sphinx.drv
building '/nix/store/ii2rprxx8gc9wwi4f15k1miaxa2lay0z-unprefixed-sphinx.drv'...
created 4 symlinks in user environment
total 0
drwxr-xr-x    6 jon wheel    192 Mar 19 10:35 .
drwxr-xr-x 4490 jon wheel 143680 Mar 19 10:35 ..
lrwxr-xr-x    1 jon wheel     67 Mar 19 10:35 bin -> /nix/store/w3sv2nyky8sk9hkyrvazvgkfmd0j9zv5-sphinxsearch-2.2.11/bin
lrwxr-xr-x    1 jon wheel     67 Mar 19 10:35 etc -> /nix/store/w3sv2nyky8sk9hkyrvazvgkfmd0j9zv5-sphinxsearch-2.2.11/etc
lrwxr-xr-x    1 jon wheel     69 Mar 19 10:35 share -> /nix/store/w3sv2nyky8sk9hkyrvazvgkfmd0j9zv5-sphinxsearch-2.2.11/share
lrwxr-xr-x    1 jon wheel     67 Mar 19 10:35 var -> /nix/store/w3sv2nyky8sk9hkyrvazvgkfmd0j9zv5-sphinxsearch-2.2.11/var
ln: failed to create symbolic link '/nix/store/qn27acr7rkg6rqcf3xfgnv22v49cbafy-unprefixed-sphinx/bin/searchd': Permission denied
builder for '/nix/store/ii2rprxx8gc9wwi4f15k1miaxa2lay0z-unprefixed-sphinx.drv' failed with exit code 1
error: build of '/nix/store/ii2rprxx8gc9wwi4f15k1miaxa2lay0z-unprefixed-sphinx.drv' failed