AC_ARG_WITH(nix, AC_HELP_STRING([--with-nix=PATH],
  [prefix of nix]),
  nix=$withval, nix=/nix-missing)
AC_SUBST(nix)
PATH="$nix/bin:$PATH"
export PATH

old_CPPFLAGS="$CPPFLAGS"
old_LIBS="$LIBS"

PKG_CHECK_MODULES([NIX], [nix-main nix-expr nix-store])

CPPFLAGS="$CPPFLAGS -I$nix/include/nix"
LDFLAGS="$LDFLAGS -L$nix/lib"
AC_CHECK_HEADER([store-api.hh], [:],
  [AC_MSG_ERROR([Nix headers not found; please install Nix or check the `--with-nix' option.])])
AC_CHECK_LIB([nixexpr], [_ZN3nix9EvalStateC1ERKSt4listISsSaISsEE], [:],
  [AC_MSG_ERROR([Nix library not found; please install Nix or check the `--with-nix' option.])])
CPPFLAGS="$old_CPPFLAGS"
LIBS="$old_LIBS"
PKG_CHECK_MODULES([BDW_GC], [bdw-gc])

        [ perl libxslt dblatex tetex nukeReferences pkgconfig boehmgc git openssl ];

        [ perl libxslt dblatex tetex nukeReferences pkgconfig nixUnstable git openssl ];

        [ "--with-nix=${nixUnstable}"
          "--with-docbook-xsl=${docbook_xsl}/xml/xsl/docbook"
        ];

        [ "--with-docbook-xsl=${docbook_xsl}/xml/xsl/docbook" ];

      configureFlags = "--with-nix=${nix}";

        [ makeWrapper libtool unzip nukeReferences pkgconfig boehmgc sqlite

        [ makeWrapper libtool unzip nukeReferences pkgconfig sqlite

hydra_eval_jobs_LDADD = -lnixmain -lnixexpr -L$(nix)/lib/nix $(BDW_GC_LIBS)

hydra_eval_jobs_LDADD = $(NIX_LIBS)

AM_CXXFLAGS =					\
 -I$(nix)/include/nix				\
  $(BDW_GC_CFLAGS)

AM_CXXFLAGS = $(NIX_CFLAGS)