diff --git a/clients/music/mp3_importer/mp3_importer.go b/clients/music/mp3_importer/mp3_importer.go
index 7846b3dbb2..82cc07ed95 100644
--- a/clients/music/mp3_importer/mp3_importer.go
+++ b/clients/music/mp3_importer/mp3_importer.go
@@ -31,7 +31,7 @@ func addMp3(ds *dataset.Dataset, filename string) {
 	}
 	defer mp3_file.Close()
 
-	mp3_data, err := types.NewBlob(bufio.NewReader(mp3_file))
+	mp3_data, err := types.NewBlob(bufio.NewReader(mp3_file), ds.Store())
 	if err != nil {
 		log.Fatalf("Failed to read mp3 data from %s: %s\n", filename, err)
 	}
diff --git a/marshal/marshal.go b/marshal/marshal.go
index 7e948e03cd..279be27426 100644
--- a/marshal/marshal.go
+++ b/marshal/marshal.go
@@ -317,7 +317,7 @@ func isNilPtrOrNilInterface(v reflect.Value) bool {
 
 func readerEncoder(v reflect.Value) types.Value {
 	d.Chk.True(v.Type().Implements(readerType))
-	blob, err := types.NewBlob(v.Interface().(io.Reader))
+	blob, err := types.NewMemoryBlob(v.Interface().(io.Reader))
 	d.Exp.NoError(err, "Failed to marshal reader into blob")
 	return blob
 }
@@ -398,10 +398,10 @@ func newMapEncoder(t reflect.Type) encoderFunc {
 
 func encodeByteSlice(v reflect.Value) types.Value {
 	if v.IsNil() {
-		nom, _ := types.NewBlob(&bytes.Buffer{})
+		nom, _ := types.NewMemoryBlob(&bytes.Buffer{})
 		return nom
 	}
-	nom, err := types.NewBlob(bytes.NewReader(v.Bytes()))
+	nom, err := types.NewMemoryBlob(bytes.NewReader(v.Bytes()))
 	if err != nil {
 		panic(err)
 	}
diff --git a/marshal/marshal_test.go b/marshal/marshal_test.go
index c66e6bf72b..423b1862c3 100644
--- a/marshal/marshal_test.go
+++ b/marshal/marshal_test.go
@@ -462,7 +462,7 @@ var pallValue = All{
 
 // Used in creating canned marshaled values below.
 func makeNewBlob(b []byte) types.Blob {
-	blob, err := types.NewBlob(bytes.NewBuffer(b))
+	blob, err := types.NewMemoryBlob(bytes.NewBuffer(b))
 	if err != nil {
 		panic(err) // Sigh
 	}
diff --git a/marshal/unmarshal_test.go b/marshal/unmarshal_test.go
index e08fc82c0b..ac4d92be0e 100644
--- a/marshal/unmarshal_test.go
+++ b/marshal/unmarshal_test.go
@@ -411,7 +411,7 @@ func byteSlice(b byte, times int) (out []byte) {
 }
 
 func blob(b ...byte) types.Blob {
-	blob, err := types.NewBlob(bytes.NewReader(b))
+	blob, err := types.NewMemoryBlob(bytes.NewReader(b))
 	if err != nil {
 		panic(err)
 	}
diff --git a/nomdl/codegen/test/struct_primitives_test.go b/nomdl/codegen/test/struct_primitives_test.go
index c7931e10d2..59f8674b0c 100644
--- a/nomdl/codegen/test/struct_primitives_test.go
+++ b/nomdl/codegen/test/struct_primitives_test.go
@@ -104,7 +104,7 @@ func TestAccessors(t *testing.T) {
 	assert.Equal("bye", st.String())
 
 	assert.True(st.Blob().Equals(types.NewEmptyBlob()))
-	b, err := types.NewBlob(strings.NewReader("hello"))
+	b, err := types.NewMemoryBlob(strings.NewReader("hello"))
 	assert.NoError(err)
 	st.SetBlob(b)
 	assert.True(st.Blob().Equals(types.NewEmptyBlob()))
diff --git a/types/blob.go b/types/blob.go
index 6f58bb4621..5f7fe8b503 100644
--- a/types/blob.go
+++ b/types/blob.go
@@ -5,6 +5,7 @@ import (
 	"io"
 
 	"github.com/attic-labs/noms/Godeps/_workspace/src/github.com/attic-labs/buzhash"
+	"github.com/attic-labs/noms/chunks"
 	"github.com/attic-labs/noms/ref"
 )
 
@@ -31,7 +32,11 @@ func NewEmptyBlob() Blob {
 	return newBlobLeaf([]byte{})
 }
 
-func NewBlob(r io.Reader) (Blob, error) {
+func NewMemoryBlob(r io.Reader) (Blob, error) {
+	return NewBlob(r, chunks.NewMemoryStore())
+}
+
+func NewBlob(r io.Reader, cs chunks.ChunkStore) (Blob, error) {
 	length := uint64(0)
 	offsets := []uint64{}
 	blobs := []Future{}
@@ -51,7 +56,7 @@ func NewBlob(r io.Reader) (Blob, error) {
 		length += n
 		offsets = append(offsets, length)
 		blob = newBlobLeaf(buf.Bytes())
-		blobs = append(blobs, futureFromValue(blob))
+		blobs = append(blobs, futureFromRef(WriteValue(blob, cs)))
 
 		if err == io.EOF {
 			break
@@ -66,7 +71,7 @@ func NewBlob(r io.Reader) (Blob, error) {
 		return blob, nil
 	}
 
-	co := compoundObject{offsets, blobs, &ref.Ref{}, nil}
+	co := compoundObject{offsets, blobs, &ref.Ref{}, cs}
 	co = splitCompoundObject(co, compoundObjectToBlobFuture)
 	return compoundBlob{co}, nil
 }
diff --git a/types/blob_test.go b/types/blob_test.go
index 250143b585..4878cbdb8e 100644
--- a/types/blob_test.go
+++ b/types/blob_test.go
@@ -20,21 +20,21 @@ func AssertSymNe(assert *assert.Assertions, a, b Value) {
 
 func TestBlobLen(t *testing.T) {
 	assert := assert.New(t)
-	b, err := NewBlob(&bytes.Buffer{})
+	b, err := NewMemoryBlob(&bytes.Buffer{})
 	assert.NoError(err)
 	assert.Equal(uint64(0), b.Len())
-	b, err = NewBlob(bytes.NewBuffer([]byte{0x01}))
+	b, err = NewMemoryBlob(bytes.NewBuffer([]byte{0x01}))
 	assert.NoError(err)
 	assert.Equal(uint64(1), b.Len())
 }
 
 func TestBlobEquals(t *testing.T) {
 	assert := assert.New(t)
-	b1, _ := NewBlob(bytes.NewBuffer([]byte{0x01}))
+	b1, _ := NewMemoryBlob(bytes.NewBuffer([]byte{0x01}))
 	b11 := b1
-	b12, _ := NewBlob(bytes.NewBuffer([]byte{0x01}))
-	b2, _ := NewBlob(bytes.NewBuffer([]byte{0x02}))
-	b3, _ := NewBlob(bytes.NewBuffer([]byte{0x02, 0x03}))
+	b12, _ := NewMemoryBlob(bytes.NewBuffer([]byte{0x01}))
+	b2, _ := NewMemoryBlob(bytes.NewBuffer([]byte{0x02}))
+	b3, _ := NewMemoryBlob(bytes.NewBuffer([]byte{0x02, 0x03}))
 	AssertSymEq(assert, b1, b11)
 	AssertSymEq(assert, b1, b12)
 	AssertSymNe(assert, b1, b2)
@@ -72,7 +72,7 @@ func TestBlobFromReaderThatReturnsDataAndError(t *testing.T) {
 	assert := assert.New(t)
 	tr := &testReader{buf: &bytes.Buffer{}}
 
-	b, err := NewBlob(tr)
+	b, err := NewMemoryBlob(tr)
 	assert.NoError(err)
 
 	actual := &bytes.Buffer{}
diff --git a/types/compound_blob_test.go b/types/compound_blob_test.go
index 76bee3cb1b..c5110fa7c3 100644
--- a/types/compound_blob_test.go
+++ b/types/compound_blob_test.go
@@ -17,13 +17,14 @@ func getTestCompoundBlob(datas ...string) compoundBlob {
 	blobs := make([]Future, len(datas))
 	offsets := make([]uint64, len(datas))
 	length := uint64(0)
+	ms := chunks.NewMemoryStore()
 	for i, s := range datas {
-		b, _ := NewBlob(bytes.NewBufferString(s))
+		b, _ := NewBlob(bytes.NewBufferString(s), ms)
 		blobs[i] = futureFromValue(b)
 		length += uint64(len(s))
 		offsets[i] = length
 	}
-	return newCompoundBlob(offsets, blobs, nil)
+	return newCompoundBlob(offsets, blobs, ms)
 }
 
 type randReader struct {
@@ -53,7 +54,7 @@ func getRandomBlob(t *testing.T) compoundBlob {
 		t.Skip("Skipping test in short mode.")
 	}
 	r := getRandomReader()
-	b, err := NewBlob(r)
+	b, err := NewMemoryBlob(r)
 	assert.NoError(t, err)
 	return b.(compoundBlob)
 }
@@ -266,7 +267,7 @@ func TestCompoundBlobSameChunksWithPrefix(t *testing.T) {
 	buf := bytes.NewBufferString("prefix")
 	r := io.MultiReader(buf, rr)
 
-	b, err := NewBlob(r)
+	b, err := NewMemoryBlob(r)
 	assert.NoError(err)
 	cb2 := b.(compoundBlob)
 
@@ -299,7 +300,7 @@ func TestCompoundBlobSameChunksWithSuffix(t *testing.T) {
 	buf := bytes.NewBufferString("suffix")
 	r := io.MultiReader(rr, buf)
 
-	b, err := NewBlob(r)
+	b, err := NewMemoryBlob(r)
 	assert.NoError(err)
 	cb2 := b.(compoundBlob)
 
diff --git a/types/decode_noms_value.go b/types/decode_noms_value.go
index 270d0849a6..106845f9de 100644
--- a/types/decode_noms_value.go
+++ b/types/decode_noms_value.go
@@ -2,6 +2,7 @@ package types
 
 import (
 	"encoding/base64"
+	"io/ioutil"
 	"strings"
 
 	"github.com/attic-labs/noms/chunks"
@@ -97,9 +98,9 @@ func (r *jsonArrayReader) readTypeRefAsTag() TypeRef {
 func (r *jsonArrayReader) readBlob(t TypeRef) Value {
 	s := r.readString()
 	decoder := base64.NewDecoder(base64.StdEncoding, strings.NewReader(s))
-	b, err := NewBlob(decoder)
+	b, err := ioutil.ReadAll(decoder)
 	d.Exp.NoError(err)
-	return b
+	return newBlobLeaf(b)
 }
 
 func (r *jsonArrayReader) readList(t TypeRef, pkg *Package) Value {
diff --git a/types/decode_noms_value_test.go b/types/decode_noms_value_test.go
index 97f18b1ca4..d0bb3680a9 100644
--- a/types/decode_noms_value_test.go
+++ b/types/decode_noms_value_test.go
@@ -83,7 +83,7 @@ func TestReadPrimitives(t *testing.T) {
 
 	test(NewString("hi"), `[%d, "hi"]`, StringKind)
 
-	blob, err := NewBlob(bytes.NewBuffer([]byte{0x00, 0x01}))
+	blob, err := NewMemoryBlob(bytes.NewBuffer([]byte{0x00, 0x01}))
 	assert.NoError(err)
 	test(blob, `[%d, "AAE="]`, BlobKind)
 }
@@ -528,7 +528,7 @@ func TestReadStructWithBlob(t *testing.T) {
 
 	v := r.readTopLevelValue().(Map)
 
-	blob, err := NewBlob(bytes.NewBuffer([]byte{0x00, 0x01}))
+	blob, err := NewMemoryBlob(bytes.NewBuffer([]byte{0x00, 0x01}))
 	assert.NoError(err)
 	assert.True(v.Get(NewString("b")).Equals(blob))
 }
diff --git a/types/encode_noms_value_test.go b/types/encode_noms_value_test.go
index dc13eadaac..3915488a13 100644
--- a/types/encode_noms_value_test.go
+++ b/types/encode_noms_value_test.go
@@ -35,7 +35,7 @@ func TestWritePrimitives(t *testing.T) {
 
 	f(StringKind, NewString("hi"), "hi")
 
-	blob, err := NewBlob(bytes.NewBuffer([]byte{0x00, 0x01}))
+	blob, err := NewMemoryBlob(bytes.NewBuffer([]byte{0x00, 0x01}))
 	assert.NoError(err)
 	f(BlobKind, blob, "AAE=")
 }
@@ -295,7 +295,7 @@ func TestWriteStructWithBlob(t *testing.T) {
 		}, Choices{})}, []ref.Ref{})
 	pkgRef := RegisterPackage(&pkg)
 	tref := MakeTypeRef(pkgRef, 0)
-	b, _ := NewBlob(bytes.NewBuffer([]byte{0x00, 0x01}))
+	b, _ := NewMemoryBlob(bytes.NewBuffer([]byte{0x00, 0x01}))
 	v := NewMap(NewString("b"), b)
 
 	w := newJsonArrayWriter(cs)
@@ -351,7 +351,7 @@ func TestWriteListOfValue(t *testing.T) {
 	cs := chunks.NewMemoryStore()
 
 	tref := MakeCompoundTypeRef(ListKind, MakePrimitiveTypeRef(ValueKind))
-	blob, _ := NewBlob(bytes.NewBuffer([]byte{0x01}))
+	blob, _ := NewMemoryBlob(bytes.NewBuffer([]byte{0x01}))
 	v := NewList(
 		Bool(true),
 		UInt8(1),
diff --git a/types/equals_test.go b/types/equals_test.go
index 156dd652e7..eb6ab6a2ae 100644
--- a/types/equals_test.go
+++ b/types/equals_test.go
@@ -44,20 +44,20 @@ func TestPrimitiveEquals(t *testing.T) {
 		func() Value { return NewString("hi") },
 		func() Value { return NewString("bye") },
 		func() Value {
-			v, _ := NewBlob(&bytes.Buffer{})
+			v, _ := NewMemoryBlob(&bytes.Buffer{})
 			return v
 		},
 		func() Value {
-			v, _ := NewBlob(bytes.NewBufferString("hi"))
+			v, _ := NewMemoryBlob(bytes.NewBufferString("hi"))
 			return v
 		},
 		func() Value {
-			v, _ := NewBlob(bytes.NewBufferString("bye"))
+			v, _ := NewMemoryBlob(bytes.NewBufferString("bye"))
 			return v
 		},
 		func() Value {
-			b1, _ := NewBlob(bytes.NewBufferString("hi"))
-			b2, _ := NewBlob(bytes.NewBufferString("bye"))
+			b1, _ := NewMemoryBlob(bytes.NewBufferString("hi"))
+			b2, _ := NewMemoryBlob(bytes.NewBufferString("bye"))
 			return newCompoundBlob([]uint64{2, 5}, []Future{futureFromValue(b1), futureFromValue(b2)}, nil)
 		},
 		func() Value { return NewList() },
diff --git a/types/map_test.go b/types/map_test.go
index 5b5e477130..eddefbf97e 100644
--- a/types/map_test.go
+++ b/types/map_test.go
@@ -166,8 +166,8 @@ func TestMapEquals(t *testing.T) {
 
 func TestMapNotStringKeys(t *testing.T) {
 	assert := assert.New(t)
-	b1, _ := NewBlob(bytes.NewBufferString("blob1"))
-	b2, _ := NewBlob(bytes.NewBufferString("blob2"))
+	b1, _ := NewMemoryBlob(bytes.NewBufferString("blob1"))
+	b2, _ := NewMemoryBlob(bytes.NewBufferString("blob2"))
 	l := []Value{
 		Bool(true), NewString("true"),
 		Bool(false), NewString("false"),
diff --git a/types/read_value_test.go b/types/read_value_test.go
index 109cfaeb24..7c5c5ac78e 100644
--- a/types/read_value_test.go
+++ b/types/read_value_test.go
@@ -21,7 +21,7 @@ func TestReadValueBlobLeafDecode(t *testing.T) {
 
 	blobLeafDecode := func(r io.Reader) Value {
 		i := decode(r)
-		b, err := NewBlob(i.(io.Reader))
+		b, err := NewMemoryBlob(i.(io.Reader))
 		assert.NoError(err)
 		return b
 	}
diff --git a/types/string.go b/types/string.go
index b884c5e60d..1341e51b6e 100644
--- a/types/string.go
+++ b/types/string.go
@@ -1,10 +1,6 @@
 package types
 
-import (
-	"bytes"
-
-	"github.com/attic-labs/noms/ref"
-)
+import "github.com/attic-labs/noms/ref"
 
 type String struct {
 	s   string
@@ -15,10 +11,6 @@ func NewString(s string) String {
 	return String{s, &ref.Ref{}}
 }
 
-func (fs String) Blob() (Blob, error) {
-	return NewBlob(bytes.NewBufferString(fs.s))
-}
-
 func (fs String) String() string {
 	return fs.s
 }
diff --git a/types/write_value_test.go b/types/write_value_test.go
index bb00a01df2..1765f36c8c 100644
--- a/types/write_value_test.go
+++ b/types/write_value_test.go
@@ -27,7 +27,7 @@ func TestWriteValue(t *testing.T) {
 
 	// Encoding details for each codec is tested elsewhere.
 	// Here we just want to make sure codecs are selected correctly.
-	b, err := NewBlob(bytes.NewBuffer([]byte{0x00, 0x01, 0x02}))
+	b, err := NewMemoryBlob(bytes.NewBuffer([]byte{0x00, 0x01, 0x02}))
 	assert.NoError(err)
 	testEncode(string([]byte{'b', ' ', 0x00, 0x01, 0x02}), b)
 
@@ -43,7 +43,7 @@ func TestWriteBlobLeaf(t *testing.T) {
 	cs := chunks.NewMemoryStore()
 
 	buf := bytes.NewBuffer([]byte{})
-	b1, err := NewBlob(buf)
+	b1, err := NewMemoryBlob(buf)
 	assert.NoError(err)
 	bl1, ok := b1.(blobLeaf)
 	assert.True(ok)
@@ -52,7 +52,7 @@ func TestWriteBlobLeaf(t *testing.T) {
 	assert.Equal("sha1-e1bc846440ec2fb557a5a271e785cd4c648883fa", r1.String())
 
 	buf = bytes.NewBufferString("Hello, World!")
-	b2, err := NewBlob(buf)
+	b2, err := NewMemoryBlob(buf)
 	assert.NoError(err)
 	bl2, ok := b2.(blobLeaf)
 	assert.True(ok)