diff --git a/nix/libpq.nix b/nix/libpq.nix
index c45956cbc..247bd2ec6 100644
--- a/nix/libpq.nix
+++ b/nix/libpq.nix
@@ -28,6 +28,7 @@ stdenv.mkDerivation {
     "--with-gssapi"
     "--with-openssl"
     "--with-system-tzdata=${tzdata}/share/zoneinfo"
+    "--sysconfdir=/etc/postgresql"
   ];
 
   nativeBuildInputs = [ pkg-config tzdata ];