diff -Naur autogen-5.18.16/agen5/guile-iface.h autogen-5.18.16.new/agen5/guile-iface.h
--- autogen-5.18.16/agen5/guile-iface.h	2018-08-26 19:44:48.000000000 +0200
+++ autogen-5.18.16.new/agen5/guile-iface.h	2020-01-19 22:13:10.699222979 +0100
@@ -9,16 +9,13 @@
 # error AutoGen does not work with this version of Guile
   choke me.
 
-#elif GUILE_VERSION < 203000
+# else
 # define AG_SCM_IS_PROC(_p)           scm_is_true( scm_procedure_p(_p))
 # define AG_SCM_LIST_P(_l)            scm_is_true( scm_list_p(_l))
 # define AG_SCM_PAIR_P(_p)            scm_is_true( scm_pair_p(_p))
 # define AG_SCM_TO_LONG(_v)           scm_to_long(_v)
 # define AG_SCM_TO_ULONG(_v)          ((unsigned long)scm_to_ulong(_v))
 
-#else
-# error unknown GUILE_VERSION
-  choke me.
 #endif
 
 #endif /* MUTATING_GUILE_IFACE_H_GUARD */
diff -Naur autogen-5.18.16/configure autogen-5.18.16.new/configure
--- autogen-5.18.16/configure	2018-08-26 19:44:54.000000000 +0200
+++ autogen-5.18.16.new/configure	2020-01-19 22:03:28.943298624 +0100
@@ -14799,7 +14799,7 @@
 		PKG_CONFIG=""
 	fi
 fi
-  _guile_versions_to_search="2.2 2.0 1.8"
+  _guile_versions_to_search="3.0 2.2 2.0 1.8"
   if test -n "$GUILE_EFFECTIVE_VERSION"; then
     _guile_tmp=""
     for v in $_guile_versions_to_search; do