anchor.diff:      # do not use "''${qemu_kvm}/bin/qemu-kvm" to avoid bound VMs to particular qemu derivations
       substituteInPlace src/lxc/lxc_conf.c \
         --replace 'lxc_path,' '"/run/libvirt/nix-emulators/libvirt_lxc",'
  -    patchShebangs . # fixes /usr/bin/python references
  +    patchShebangs .
     ''
     + (lib.concatStringsSep "\n" (lib.mapAttrsToList patchBuilder overrides));
   
  
positive.code: 
    buildInputs = [
      bash-completion pkg-config
      libxml2 gnutls perl python2 readline gettext libtasn1 libgcrypt yajl
      libxslt xhtml1 perlPackages.XMLXPath curl libpcap glib dbus
    ] ++ optionals stdenv.isLinux [
      audit libpciaccess lvm2 util-linux systemd libnl numad zfs
  
negative.code: { lib, stdenv, fetchurl, fetchgit
  , makeWrapper, autoreconfHook, fetchpatch
  , coreutils, libxml2, gnutls, perl, python3, attr, glib, docutils
  , iproute, readline, lvm2, util-linux, systemd, libpciaccess, gettext
  , libtasn1, iptables, ebtables, libgcrypt, yajl, pmutils, libcap_ng, libapparmor
  , dnsmasq, libnl, libpcap, libxslt, xhtml1, numad, numactl, perlPackages
  