public Builder addRegistry(final IoRegistry registry) {
            if (null == registry) throw new IllegalArgumentException("The registry cannot be null");

            final List<Pair<Class, CustomTypeSerializer>> classSerializers = registry.find(GraphBinaryIo.class, CustomTypeSerializer.class);
            for (Pair<Class,CustomTypeSerializer> cs : classSerializers) {
                addCustomType(cs.getValue0(), cs.getValue1());
            }

            return this;
        }
Add {@link CustomTypeSerializer} by way of an {@link IoRegistry}. The registry entries should be bound to
{@link GraphBinaryIo}.
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/structure/io/binary/TypeSerializerRegistry.java