It seems like this is sufficient to make it compatible (works in my tests locally). Is there a more "official" package already available (for compatibility reasons)?
const multiformats = require("multiformats/basics.js");
const { Buffer } = require("buffer");
const { util: { serialize, deserialize } } = require("ipld-dag-pb");
const dagpb = {
encode: serialize,
decode: buffer => deserialize(Buffer.from(buffer)),
code: 0x70,
name: "dag-pb",
};
multiformats.multicodec.add(dagpb);