dnl Determine the appropriate default list of substitute URLs (GnuTLS
dnl is required so we can default to 'https'.)
- guix_substitute_urls="https://mirror.hydra.gnu.org"
+ case "x$host_cpu" in
+ xaarch64)
+ # Currently only berlin.guixsd.org provides aarch64 binaries.
+ guix_substitute_urls="https://berlin.guixsd.org"
+ ;;
+ *)
+ guix_substitute_urls="https://mirror.hydra.gnu.org"
+ ;;
+ esac
AC_MSG_CHECKING([for default substitute URLs])
AC_MSG_RESULT([$guix_substitute_urls])