try fix script

lib.nix

@@ -1,8 +1,7 @@
 { pkgs }:
 let
   inherit (pkgs) lib;
-  pwd = builtins.getEnv "PWD";
-  runtime = "${pwd}/.compose";
+  runtime = ".compose";
 in
 {
   mkWrapper =
@@ -144,6 +143,7 @@ in
         text = ''
             set -euo pipefail
             export PGDATA=${data_dir} PGHOST=${runtimeDir} PGPORT=${builtins.toString port}
+          pwd
             mkdir -p ${lib.escapeShellArg runtimeDir}
             ${setupScript}/bin/setup-postgres
             exec ${package}/bin/postgres