Field (@NotNull YamlMetaClass metaClass) { return metaClass.addFeature(new Field("anything:<any-key>", getInstance())) .withAnyName() .withRelationSpecificType(Field.Relation.SEQUENCE_ITEM, getInstance()) .withRelationSpecificType(Field.Relation.SCALAR_VALUE, YamlAnyScalarType.getInstance()) .withEmptyValueAllowed(true); }