Five minutes in: not all nodes are serializable.

Hopefully if we come up with a good way to flip one node impl into another,
we'll be able to come up with an easy interface for "this is referencing
an in-memory structure type of mine, but hashed as CBOR native standard".

.gitmodules

+[submodule ".gopath/src/github.com/polydawn/refmt"]
+	path = .gopath/src/github.com/polydawn/refmt
+	url = https://github.com/polydawn/refmt

refmt @ e22c00b5

+Subproject commit e22c00b5cd9b3c32666b21d623a0d2b6fdcbc39e

impl/bind/boundNode.go

+package ipldbind
+
+import (
+	"reflect"
+
+	"github.com/ipld/go-ipld-prime"
+	"github.com/polydawn/refmt/obj/atlas"
+)
+
+var (
+	_ ipld.Node = &Node{}
+)
+
+/*
+	Node binds to some Go object in memory, using the definitions provided
+	by refmt's object atlasing tools.
+
+	This binding does not provide a serialization valid for hashing; to
+	compute a CID, you'll have to convert to another kind of node.
+	If you're not sure which kind serializable node to use, try `ipldcbor.Node`.
+*/
+type Node struct {
+	bound reflect.Value
+	atlas atlas.Atlas
+}

impl/cbor/cborNode.go

@@ -4,7 +4,13 @@ import (
 	"github.com/ipld/go-ipld-prime"
 )
 
-var _ ipld.Node = &Node{}
+var (
+	_ ipld.Node             = &Node{}
+	_ ipld.SerializableNode = &Node{}
+)
 
+/*
+	Node in ipldcbor is implemented // ... if you want to hash it or write it: both are better streamed (especially the former)
+*/
 type Node struct {
 }

node.go

@@ -2,3 +2,9 @@ package ipld
 
 type Node interface {
 }
+
+type SerializableNode interface {
+}
+
+type MutableNode interface {
+}