code: function (node, cb) {
      var opts = {
        hash: node.key,
        log: node.log,
        seq: node.seq,
        identity: node.identity,
        signature: node.signature,
        valueEncoding: 'binary'
      }
      dag.add(node.links, node.value, opts, function (err) {
        if (!err) return afterAdd(cb)
        if (!err.notFound) return cb(err)
        incoming.push(node, cb)
      })
    }
docs: Add a received remote node to our local hyperlog. It is normal for the insertion to sometimes fail: we may have received a node that depends on another node from a log we haven't yet received. If so, enqueue it into 'incoming' and continue trying to re-insert it until its dependencies are also present.