+dnl Better be verbose.
+AC_MSG_CHECKING([for the store directory])
+AC_MSG_RESULT([$storedir])
+
+AC_ARG_ENABLE([daemon],
+ [AS_HELP_STRING([--disable-daemon], [build the Nix daemon (C++)])],
+ [guix_build_daemon="$enableval"],
+ [guix_build_daemon="yes"])
+
+# Prepare a version of $localstatedir & co. that does not contain references
+# to shell variables.
+guix_prefix="`eval echo $prefix | sed -e"s|NONE|/usr/local|g"`"
+guix_localstatedir="`eval echo $localstatedir | sed -e "s|NONE|$guix_prefix|g"`"
+guix_sysconfdir="`eval echo $sysconfdir | sed -e "s|NONE|$guix_prefix|g"`"
+guix_sbindir="`eval echo $sbindir | sed -e "s|NONE|$guix_prefix|g"`"
+AC_SUBST([guix_localstatedir])
+AC_SUBST([guix_sysconfdir])
+AC_SUBST([guix_sbindir])
+
+dnl We require the pkg.m4 set of macros from pkg-config.
+dnl Make sure it's available.
+m4_pattern_forbid([PKG_CHECK_MODULES])
+
+PKG_CHECK_MODULES([GUILE], [guile-2.0 >= 2.0.5])