diff --git a/unixfs/ipld-merkledag/hamt/hamt.go b/unixfs/ipld-merkledag/hamt/hamt.go
index 6887a148d..4d3bd3b8e 100644
--- a/unixfs/ipld-merkledag/hamt/hamt.go
+++ b/unixfs/ipld-merkledag/hamt/hamt.go
@@ -52,7 +52,7 @@ type Shard struct {
 	tableSize    int
 	tableSizeLg2 int
 
-	prefix   *cid.Prefix
+	builder  cid.Builder
 	hashFunc uint64
 
 	prefixPadStr string
@@ -124,25 +124,25 @@ func NewHamtFromDag(dserv ipld.DAGService, nd ipld.Node) (*Shard, error) {
 	ds.children = make([]child, len(pbnd.Links()))
 	ds.bitfield.SetBytes(pbd.GetData())
 	ds.hashFunc = pbd.GetHashType()
-	ds.prefix = &ds.nd.Prefix
+	ds.builder = ds.nd.CidBuilder()
 
 	return ds, nil
 }
 
-// SetPrefix sets the CID Prefix
-func (ds *Shard) SetPrefix(prefix *cid.Prefix) {
-	ds.prefix = prefix
+// SetCidBuilder sets the CID Builder
+func (ds *Shard) SetCidBuilder(builder cid.Builder) {
+	ds.builder = builder
 }
 
-// Prefix gets the CID Prefix, may be nil if unset
-func (ds *Shard) Prefix() *cid.Prefix {
-	return ds.prefix
+// CidBuilder gets the CID Builder, may be nil if unset
+func (ds *Shard) CidBuilder() cid.Builder {
+	return ds.builder
 }
 
 // Node serializes the HAMT structure into a merkledag node with unixfs formatting
 func (ds *Shard) Node() (ipld.Node, error) {
 	out := new(dag.ProtoNode)
-	out.SetPrefix(ds.prefix)
+	out.SetCidBuilder(ds.builder)
 
 	cindex := 0
 	// TODO: optimized 'for each set bit'
@@ -494,7 +494,7 @@ func (ds *Shard) modifyValue(ctx context.Context, hv *hashBits, key string, val
 		if err != nil {
 			return err
 		}
-		ns.prefix = ds.prefix
+		ns.builder = ds.builder
 		chhv := &hashBits{
 			b:        hash([]byte(child.key)),
 			consumed: hv.consumed,
diff --git a/unixfs/ipld-merkledag/importer/helpers/dagbuilder.go b/unixfs/ipld-merkledag/importer/helpers/dagbuilder.go
index 387b26304..4c897fd48 100644
--- a/unixfs/ipld-merkledag/importer/helpers/dagbuilder.go
+++ b/unixfs/ipld-merkledag/importer/helpers/dagbuilder.go
@@ -19,14 +19,14 @@ import (
 // DagBuilderHelper wraps together a bunch of objects needed to
 // efficiently create unixfs dag trees
 type DagBuilderHelper struct {
-	dserv     ipld.DAGService
-	spl       chunker.Splitter
-	recvdErr  error
-	rawLeaves bool
-	nextData  []byte // the next item to return.
-	maxlinks  int
-	batch     *ipld.Batch
-	prefix    *cid.Prefix
+	dserv      ipld.DAGService
+	spl        chunker.Splitter
+	recvdErr   error
+	rawLeaves  bool
+	nextData   []byte // the next item to return.
+	maxlinks   int
+	batch      *ipld.Batch
+	cidBuilder cid.Builder
 
 	// Filestore support variables.
 	// ----------------------------
@@ -53,8 +53,8 @@ type DagBuilderParams struct {
 	// instead of using the unixfs TRaw type
 	RawLeaves bool
 
-	// CID Prefix to use if set
-	Prefix *cid.Prefix
+	// CID Builder to use if set
+	CidBuilder cid.Builder
 
 	// DAGService to write blocks to (required)
 	Dagserv ipld.DAGService
@@ -73,12 +73,12 @@ type DagBuilderParams struct {
 // chunker.Splitter as data source.
 func (dbp *DagBuilderParams) New(spl chunker.Splitter) *DagBuilderHelper {
 	db := &DagBuilderHelper{
-		dserv:     dbp.Dagserv,
-		spl:       spl,
-		rawLeaves: dbp.RawLeaves,
-		prefix:    dbp.Prefix,
-		maxlinks:  dbp.Maxlinks,
-		batch:     ipld.NewBatch(context.TODO(), dbp.Dagserv),
+		dserv:      dbp.Dagserv,
+		spl:        spl,
+		rawLeaves:  dbp.RawLeaves,
+		cidBuilder: dbp.CidBuilder,
+		maxlinks:   dbp.Maxlinks,
+		batch:      ipld.NewBatch(context.TODO(), dbp.Dagserv),
 	}
 	if fi, ok := spl.Reader().(files.FileInfo); dbp.NoCopy && ok {
 		db.fullPath = fi.AbsPath()
@@ -141,13 +141,13 @@ func (db *DagBuilderHelper) NewUnixfsNode() *UnixfsNode {
 		node: new(dag.ProtoNode),
 		ufmt: ft.NewFSNode(ft.TFile),
 	}
-	n.SetPrefix(db.prefix)
+	n.SetCidBuilder(db.cidBuilder)
 	return n
 }
 
-// GetPrefix returns the internal `cid.Prefix` set in the builder.
-func (db *DagBuilderHelper) GetPrefix() *cid.Prefix {
-	return db.prefix
+// GetCidBuilder returns the internal `cid.CidBuilder` set in the builder.
+func (db *DagBuilderHelper) GetCidBuilder() cid.Builder {
+	return db.cidBuilder
 }
 
 // NewLeaf creates a leaf node filled with data.  If rawLeaves is
@@ -160,13 +160,13 @@ func (db *DagBuilderHelper) NewLeaf(data []byte) (*UnixfsNode, error) {
 	}
 
 	if db.rawLeaves {
-		if db.prefix == nil {
+		if db.cidBuilder == nil {
 			return &UnixfsNode{
 				rawnode: dag.NewRawNode(data),
 				raw:     true,
 			}, nil
 		}
-		rawnode, err := dag.NewRawNodeWPrefix(data, *db.prefix)
+		rawnode, err := dag.NewRawNodeWPrefix(data, db.cidBuilder)
 		if err != nil {
 			return nil, err
 		}
@@ -194,10 +194,10 @@ func (db *DagBuilderHelper) NewLeafNode(data []byte) (ipld.Node, error) {
 
 	if db.rawLeaves {
 		// Encapsulate the data in a raw node.
-		if db.prefix == nil {
+		if db.cidBuilder == nil {
 			return dag.NewRawNode(data), nil
 		}
-		rawnode, err := dag.NewRawNodeWPrefix(data, *db.prefix)
+		rawnode, err := dag.NewRawNodeWPrefix(data, db.cidBuilder)
 		if err != nil {
 			return nil, err
 		}
@@ -229,7 +229,7 @@ func (db *DagBuilderHelper) newUnixfsBlock() *UnixfsNode {
 		node: new(dag.ProtoNode),
 		ufmt: ft.NewFSNode(ft.TRaw),
 	}
-	n.SetPrefix(db.prefix)
+	n.SetCidBuilder(db.cidBuilder)
 	return n
 }
 
@@ -401,7 +401,7 @@ type FSNodeOverDag struct {
 func (db *DagBuilderHelper) NewFSNodeOverDag(fsNodeType pb.Data_DataType) *FSNodeOverDag {
 	node := new(FSNodeOverDag)
 	node.dag = new(dag.ProtoNode)
-	node.dag.SetPrefix(db.GetPrefix())
+	node.dag.SetCidBuilder(db.GetCidBuilder())
 
 	node.file = ft.NewFSNode(fsNodeType)
 
diff --git a/unixfs/ipld-merkledag/importer/helpers/helpers.go b/unixfs/ipld-merkledag/importer/helpers/helpers.go
index 6fb0f83c8..a2e443ea3 100644
--- a/unixfs/ipld-merkledag/importer/helpers/helpers.go
+++ b/unixfs/ipld-merkledag/importer/helpers/helpers.go
@@ -60,9 +60,9 @@ func NewUnixfsNodeFromDag(nd *dag.ProtoNode) (*UnixfsNode, error) {
 	}, nil
 }
 
-// SetPrefix sets the CID Prefix
-func (n *UnixfsNode) SetPrefix(prefix *cid.Prefix) {
-	n.node.SetPrefix(prefix)
+// SetCidBuilder sets the CID Builder
+func (n *UnixfsNode) SetCidBuilder(builder cid.Builder) {
+	n.node.SetCidBuilder(builder)
 }
 
 // NumChildren returns the number of children referenced by this UnixfsNode.
diff --git a/unixfs/ipld-merkledag/importer/importer_test.go b/unixfs/ipld-merkledag/importer/importer_test.go
index 823abaa4b..b39aff57d 100644
--- a/unixfs/ipld-merkledag/importer/importer_test.go
+++ b/unixfs/ipld-merkledag/importer/importer_test.go
@@ -38,7 +38,7 @@ func getTrickleDag(t testing.TB, size int64, blksize int64) (ipld.Node, ipld.DAG
 
 func TestStableCid(t *testing.T) {
 	ds := mdtest.Mock()
-	buf := make([]byte, 10 * 1024 * 1024)
+	buf := make([]byte, 10*1024*1024)
 	u.NewSeededRand(0xdeadbeef).Read(buf)
 	r := bytes.NewReader(buf)
 
diff --git a/unixfs/ipld-merkledag/io/directory.go b/unixfs/ipld-merkledag/io/directory.go
index 89864566e..aa1ec8de7 100644
--- a/unixfs/ipld-merkledag/io/directory.go
+++ b/unixfs/ipld-merkledag/io/directory.go
@@ -29,8 +29,8 @@ var DefaultShardWidth = 256
 // (which is the main consumer of this interface).
 type Directory interface {
 
-	// SetPrefix sets the CID prefix of the root node.
-	SetPrefix(*cid.Prefix)
+	// SetCidBuilder sets the CID Builder of the root node.
+	SetCidBuilder(cid.Builder)
 
 	// AddChild adds a (name, key) pair to the root node.
 	AddChild(context.Context, string, ipld.Node) error
@@ -51,8 +51,8 @@ type Directory interface {
 	// GetNode returns the root of this directory.
 	GetNode() (ipld.Node, error)
 
-	// GetPrefix returns the CID Prefix used.
-	GetPrefix() *cid.Prefix
+	// GetCidBuilder returns the CID Builder used.
+	GetCidBuilder() cid.Builder
 }
 
 // TODO: Evaluate removing `dserv` from this layer and providing it in MFS.
@@ -127,9 +127,9 @@ func NewDirectoryFromNode(dserv ipld.DAGService, node ipld.Node) (Directory, err
 	return nil, ErrNotADir
 }
 
-// SetPrefix implements the `Directory` interface.
-func (d *BasicDirectory) SetPrefix(prefix *cid.Prefix) {
-	d.node.SetPrefix(prefix)
+// SetCidBuilder implements the `Directory` interface.
+func (d *BasicDirectory) SetCidBuilder(builder cid.Builder) {
+	d.node.SetCidBuilder(builder)
 }
 
 // AddChild implements the `Directory` interface. It adds (or replaces)
@@ -179,9 +179,9 @@ func (d *BasicDirectory) GetNode() (ipld.Node, error) {
 	return d.node, nil
 }
 
-// GetPrefix implements the `Directory` interface.
-func (d *BasicDirectory) GetPrefix() *cid.Prefix {
-	return &d.node.Prefix
+// GetCidBuilder implements the `Directory` interface.
+func (d *BasicDirectory) GetCidBuilder() cid.Builder {
+	return d.node.CidBuilder()
 }
 
 // SwitchToSharding returns a HAMT implementation of this directory.
@@ -193,7 +193,7 @@ func (d *BasicDirectory) SwitchToSharding(ctx context.Context) (Directory, error
 	if err != nil {
 		return nil, err
 	}
-	shard.SetPrefix(&d.node.Prefix)
+	shard.SetCidBuilder(d.node.CidBuilder())
 	hamtDir.shard = shard
 
 	for _, lnk := range d.node.Links() {
@@ -211,9 +211,9 @@ func (d *BasicDirectory) SwitchToSharding(ctx context.Context) (Directory, error
 	return hamtDir, nil
 }
 
-// SetPrefix implements the `Directory` interface.
-func (d *HAMTDirectory) SetPrefix(prefix *cid.Prefix) {
-	d.shard.SetPrefix(prefix)
+// SetCidBuilder implements the `Directory` interface.
+func (d *HAMTDirectory) SetCidBuilder(builder cid.Builder) {
+	d.shard.SetCidBuilder(builder)
 }
 
 // AddChild implements the `Directory` interface.
@@ -251,7 +251,7 @@ func (d *HAMTDirectory) GetNode() (ipld.Node, error) {
 	return d.shard.Node()
 }
 
-// GetPrefix implements the `Directory` interface.
-func (d *HAMTDirectory) GetPrefix() *cid.Prefix {
-	return d.shard.Prefix()
+// GetCidBuilder implements the `Directory` interface.
+func (d *HAMTDirectory) GetCidBuilder() cid.Builder {
+	return d.shard.CidBuilder()
 }
diff --git a/unixfs/ipld-merkledag/mod/dagmodifier.go b/unixfs/ipld-merkledag/mod/dagmodifier.go
index 09665b80c..f6e5f4820 100644
--- a/unixfs/ipld-merkledag/mod/dagmodifier.go
+++ b/unixfs/ipld-merkledag/mod/dagmodifier.go
@@ -256,7 +256,7 @@ func (dm *DagModifier) modifyDag(n ipld.Node, offset uint64) (*cid.Cid, error) {
 
 			nd := new(mdag.ProtoNode)
 			nd.SetData(b)
-			nd.SetPrefix(&nd0.Prefix)
+			nd.SetCidBuilder(nd0.CidBuilder())
 			err = dm.dagserv.Add(dm.ctx, nd)
 			if err != nil {
 				return nil, err
@@ -345,10 +345,10 @@ func (dm *DagModifier) appendData(nd ipld.Node, spl chunker.Splitter) (ipld.Node
 	switch nd := nd.(type) {
 	case *mdag.ProtoNode, *mdag.RawNode:
 		dbp := &help.DagBuilderParams{
-			Dagserv:   dm.dagserv,
-			Maxlinks:  help.DefaultLinksPerBlock,
-			Prefix:    &dm.Prefix,
-			RawLeaves: dm.RawLeaves,
+			Dagserv:    dm.dagserv,
+			Maxlinks:   help.DefaultLinksPerBlock,
+			CidBuilder: dm.Prefix,
+			RawLeaves:  dm.RawLeaves,
 		}
 		return trickle.Append(dm.ctx, nd, dbp.New(spl))
 	default:
diff --git a/unixfs/ipld-merkledag/test/utils.go b/unixfs/ipld-merkledag/test/utils.go
index cc8fe4dd0..fdd307c56 100644
--- a/unixfs/ipld-merkledag/test/utils.go
+++ b/unixfs/ipld-merkledag/test/utils.go
@@ -61,10 +61,10 @@ func GetNode(t testing.TB, dserv ipld.DAGService, data []byte, opts NodeOpts) ip
 	in := bytes.NewReader(data)
 
 	dbp := h.DagBuilderParams{
-		Dagserv:   dserv,
-		Maxlinks:  h.DefaultLinksPerBlock,
-		Prefix:    &opts.Prefix,
-		RawLeaves: opts.RawLeavesUsed,
+		Dagserv:    dserv,
+		Maxlinks:   h.DefaultLinksPerBlock,
+		CidBuilder: opts.Prefix,
+		RawLeaves:  opts.RawLeavesUsed,
 	}
 
 	node, err := trickle.Layout(dbp.New(SizeSplitterGen(500)(in)))