diff --git a/enterprise/b/containers_btree.go b/enterprise/b/containers_btree.go
index 69075e9e7..66d20b9ca 100644
--- a/enterprise/b/containers_btree.go
+++ b/enterprise/b/containers_btree.go
@@ -2,6 +2,7 @@ package b
 
 import (
 	"io"
+	"log"
 
 	"github.com/pilosa/pilosa/roaring"
 )
@@ -10,17 +11,26 @@ func cmp(a, b uint64) int {
 	return int(a - b)
 }
 
+type BTreeContainers struct {
+	tree *Tree
+
+	lastKey       uint64
+	lastContainer *roaring.Container
+}
+
 func NewBTreeContainers() *BTreeContainers {
 	return &BTreeContainers{
 		tree: TreeNew(cmp),
 	}
 }
 
-type BTreeContainers struct {
-	tree *Tree
-
-	lastKey       uint64
-	lastContainer *roaring.Container
+func NewBTreeBitmap(a ...uint64) *roaring.Bitmap {
+	log.Println("btree bitmap")
+	b := &roaring.Bitmap{
+		Containers: NewBTreeContainers(),
+	}
+	b.Add(a...)
+	return b
 }
 
 func (btc *BTreeContainers) Get(key uint64) *roaring.Container {
@@ -96,7 +106,7 @@ func (btc *BTreeContainers) GetOrCreate(key uint64) *roaring.Container {
 	return btc.lastContainer
 }
 
-func (btc *BTreeContainers) Clone() roaring.Containerser {
+func (btc *BTreeContainers) Clone() roaring.Containers {
 	nbtc := NewBTreeContainers()
 
 	itr, err := btc.tree.SeekFirst()
diff --git a/fragment.go b/fragment.go
index 7168f4443..3c40f1e19 100644
--- a/fragment.go
+++ b/fragment.go
@@ -189,7 +189,7 @@ func (f *Fragment) Open() error {
 func (f *Fragment) openStorage() error {
 	// Create a roaring bitmap to serve as storage for the slice.
 	if f.storage == nil {
-		f.storage = roaring.NewBitmap()
+		f.storage = roaring.NewFileBitmap()
 	}
 	// Open the data file to be mmap'd and used as an ops log.
 	file, err := os.OpenFile(f.path, os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)
diff --git a/roaring/containers.go b/roaring/containers.go
index ecc69b6fd..f91360ee3 100644
--- a/roaring/containers.go
+++ b/roaring/containers.go
@@ -7,6 +7,10 @@ type SliceContainers struct {
 	lastContainer *Container
 }
 
+func NewSliceContainers() *SliceContainers {
+	return &SliceContainers{}
+}
+
 func (sc *SliceContainers) Get(key uint64) *Container {
 	i := search64(sc.keys, key)
 	if i < 0 {
@@ -83,8 +87,8 @@ func (sc *SliceContainers) GetOrCreate(key uint64) *Container {
 	return sc.lastContainer
 }
 
-func (sc *SliceContainers) Clone() Containerser {
-	other := NewContainers()
+func (sc *SliceContainers) Clone() Containers {
+	other := NewSliceContainers()
 	other.keys = make([]uint64, len(sc.keys))
 	other.containers = make([]*Container, len(sc.containers))
 	copy(other.keys, sc.keys)
diff --git a/roaring/containers_btree.go b/roaring/containers_btree.go
deleted file mode 100644
index 008007a48..000000000
--- a/roaring/containers_btree.go
+++ /dev/null
@@ -1,9 +0,0 @@
-// +build enterprise
-
-package roaring
-
-import "github.com/pilosa/pilosa/enterprise/b"
-
-func NewContainers() *b.BTreeContainers {
-	return &b.BTreeContainers{}
-}
diff --git a/roaring/containers_slice.go b/roaring/containers_slice.go
deleted file mode 100644
index 8642dbabc..000000000
--- a/roaring/containers_slice.go
+++ /dev/null
@@ -1,7 +0,0 @@
-// +build !enterprise
-
-package roaring
-
-func NewContainers() *SliceContainers {
-	return &SliceContainers{}
-}
diff --git a/roaring/containers_test.go b/roaring/containers_test.go
index 9acf9cc08..cb92e5d50 100644
--- a/roaring/containers_test.go
+++ b/roaring/containers_test.go
@@ -9,11 +9,11 @@ import (
 //	testContainersIterator(btc, t)
 //}
 func TestContainersBTreeIterator(t *testing.T) {
-	slc := NewContainers()
+	slc := NewSliceContainers()
 	testContainersIterator(slc, t)
 
 }
-func testContainersIterator(cs Containerser, t *testing.T) {
+func testContainersIterator(cs Containers, t *testing.T) {
 	itr, found := cs.Iterator(0)
 	if found {
 		t.Fatalf("shouldn't have found 0 in empty btc")
diff --git a/roaring/roaring.go b/roaring/roaring.go
index f279f20d5..88dbf3c31 100644
--- a/roaring/roaring.go
+++ b/roaring/roaring.go
@@ -64,7 +64,7 @@ const (
 	maxContainerVal = 0xffff
 )
 
-type Containerser interface {
+type Containers interface {
 	// Get returns nil if the key does not exist.
 	Get(key uint64) *Container
 
@@ -82,7 +82,7 @@ type Containerser interface {
 	GetOrCreate(key uint64) *Container
 
 	// Clone does a deep copy of Containers, including cloning all containers contained.
-	Clone() Containerser
+	Clone() Containers
 
 	// Last returns the highest key and associated container.
 	Last() (key uint64, c *Container)
@@ -103,7 +103,7 @@ type Contiterator interface {
 
 // Bitmap represents a roaring bitmap.
 type Bitmap struct {
-	conts Containerser
+	Containers Containers
 
 	// Number of operations written to the writer.
 	opN int
@@ -115,19 +115,14 @@ type Bitmap struct {
 // NewBitmap returns a Bitmap with an initial set of values.
 func NewBitmap(a ...uint64) *Bitmap {
 	b := &Bitmap{
-		conts: NewContainers(),
+		Containers: NewSliceContainers(),
 	}
 	b.Add(a...)
 	return b
 }
 
-//func NewBTreeBitmap(a ...uint64) *Bitmap {
-//	b := &Bitmap{
-//		conts: NewBTreeContainers(),
-//	}
-//	b.Add(a...)
-//	return b
-//}
+// NewFileBitmap returns a Bitmap with an initial set of values.
+var NewFileBitmap func(a ...uint64) *Bitmap = NewBitmap
 
 // Clone returns a heap allocated copy of the bitmap.
 // Note: The OpWriter IS NOT copied to the new bitmap.
@@ -138,7 +133,7 @@ func (b *Bitmap) Clone() *Bitmap {
 
 	// Create a copy of the bitmap structure.
 	other := &Bitmap{
-		conts: b.conts.Clone(),
+		Containers: b.Containers.Clone(),
 	}
 
 	return other
@@ -167,13 +162,13 @@ func (b *Bitmap) Add(a ...uint64) (changed bool, err error) {
 }
 
 func (b *Bitmap) add(v uint64) bool {
-	cont := b.conts.GetOrCreate(highbits(v))
+	cont := b.Containers.GetOrCreate(highbits(v))
 	return cont.add(lowbits(v))
 }
 
 // Contains returns true if v is in the bitmap.
 func (b *Bitmap) Contains(v uint64) bool {
-	c := b.conts.Get(highbits(v))
+	c := b.Containers.Get(highbits(v))
 	if c == nil {
 		return false
 	}
@@ -201,7 +196,7 @@ func (b *Bitmap) Remove(a ...uint64) (changed bool, err error) {
 }
 
 func (b *Bitmap) remove(v uint64) bool {
-	c := b.conts.Get(highbits(v))
+	c := b.Containers.Get(highbits(v))
 	if c == nil {
 		return false
 	}
@@ -212,18 +207,18 @@ func (b *Bitmap) remove(v uint64) bool {
 // Max returns the highest value in the bitmap.
 // Returns zero if the bitmap is empty.
 func (b *Bitmap) Max() uint64 {
-	if b.conts.Size() == 0 {
+	if b.Containers.Size() == 0 {
 		return 0
 	}
 
-	hb, c := b.conts.Last()
+	hb, c := b.Containers.Last()
 	lb := c.max()
 	return hb<<16 | uint64(lb)
 }
 
 // Count returns the number of bits set in the bitmap.
 func (b *Bitmap) Count() (n uint64) {
-	citer, _ := b.conts.Iterator(0)
+	citer, _ := b.Containers.Iterator(0)
 	for citer.Next() {
 		_, c := citer.Value()
 		n += uint64(c.n)
@@ -233,14 +228,14 @@ func (b *Bitmap) Count() (n uint64) {
 
 // CountRange returns the number of bits set between [start, end).
 func (b *Bitmap) CountRange(start, end uint64) (n uint64) {
-	if b.conts.Size() == 0 {
+	if b.Containers.Size() == 0 {
 		return
 	}
 
 	skey := highbits(start)
 	ekey := highbits(end)
 
-	citer, found := b.conts.Iterator(highbits(start))
+	citer, found := b.Containers.Iterator(highbits(start))
 	// If range is entirely in one container then just count that range.
 	if found && skey == ekey {
 		citer.Next()
@@ -328,21 +323,21 @@ func (b *Bitmap) OffsetRange(offset, start, end uint64) *Bitmap {
 
 	off := highbits(offset)
 	hi0, hi1 := highbits(start), highbits(end)
-	citer, _ := b.conts.Iterator(hi0)
+	citer, _ := b.Containers.Iterator(hi0)
 	other := NewBitmap()
 	for citer.Next() {
 		k, c := citer.Value()
 		if k >= hi1 {
 			break
 		}
-		other.conts.Put(off+(k-hi0), c)
+		other.Containers.Put(off+(k-hi0), c)
 	}
 	return other
 }
 
 // container returns the container with the given key.
 func (b *Bitmap) container(key uint64) *Container {
-	return b.conts.Get(key)
+	return b.Containers.Get(key)
 }
 
 // IntersectionCount returns the number of set bits that would result in an
@@ -350,8 +345,8 @@ func (b *Bitmap) container(key uint64) *Container {
 // intersecting the two and counting the result.
 func (b *Bitmap) IntersectionCount(other *Bitmap) uint64 {
 	var n uint64
-	iiter, _ := b.conts.Iterator(0)
-	jiter, _ := other.conts.Iterator(0)
+	iiter, _ := b.Containers.Iterator(0)
+	jiter, _ := other.Containers.Iterator(0)
 	i, j := iiter.Next(), jiter.Next()
 	ki, ci := iiter.Value()
 	kj, cj := jiter.Value()
@@ -375,8 +370,8 @@ func (b *Bitmap) IntersectionCount(other *Bitmap) uint64 {
 // Intersect returns the intersection of b and other.
 func (b *Bitmap) Intersect(other *Bitmap) *Bitmap {
 	output := NewBitmap()
-	iiter, _ := b.conts.Iterator(0)
-	jiter, _ := other.conts.Iterator(0)
+	iiter, _ := b.Containers.Iterator(0)
+	jiter, _ := other.Containers.Iterator(0)
 	i, j := iiter.Next(), jiter.Next()
 	ki, ci := iiter.Value()
 	kj, cj := jiter.Value()
@@ -388,7 +383,7 @@ func (b *Bitmap) Intersect(other *Bitmap) *Bitmap {
 			j = jiter.Next()
 			kj, cj = jiter.Value()
 		} else { // ki == kj
-			output.conts.Put(ki, intersect(ci, cj))
+			output.Containers.Put(ki, intersect(ci, cj))
 			i, j = iiter.Next(), jiter.Next()
 			ki, ci = iiter.Value()
 			kj, cj = jiter.Value()
@@ -401,22 +396,22 @@ func (b *Bitmap) Intersect(other *Bitmap) *Bitmap {
 func (b *Bitmap) Union(other *Bitmap) *Bitmap {
 	output := NewBitmap()
 
-	iiter, _ := b.conts.Iterator(0)
-	jiter, _ := other.conts.Iterator(0)
+	iiter, _ := b.Containers.Iterator(0)
+	jiter, _ := other.Containers.Iterator(0)
 	i, j := iiter.Next(), jiter.Next()
 	ki, ci := iiter.Value()
 	kj, cj := jiter.Value()
 	for i || j {
 		if i && (!j || ki < kj) {
-			output.conts.Put(ki, ci.Clone())
+			output.Containers.Put(ki, ci.Clone())
 			i = iiter.Next()
 			ki, ci = iiter.Value()
 		} else if j && (!i || ki > kj) {
-			output.conts.Put(kj, cj.Clone())
+			output.Containers.Put(kj, cj.Clone())
 			j = jiter.Next()
 			kj, cj = jiter.Value()
 		} else { // ki == kj
-			output.conts.Put(ki, union(ci, cj))
+			output.Containers.Put(ki, union(ci, cj))
 			i, j = iiter.Next(), jiter.Next()
 			ki, ci = iiter.Value()
 			kj, cj = jiter.Value()
@@ -429,21 +424,21 @@ func (b *Bitmap) Union(other *Bitmap) *Bitmap {
 func (b *Bitmap) Difference(other *Bitmap) *Bitmap {
 	output := NewBitmap()
 
-	iiter, _ := b.conts.Iterator(0)
-	jiter, _ := other.conts.Iterator(0)
+	iiter, _ := b.Containers.Iterator(0)
+	jiter, _ := other.Containers.Iterator(0)
 	i, j := iiter.Next(), jiter.Next()
 	ki, ci := iiter.Value()
 	kj, cj := jiter.Value()
 	for i || j {
 		if i && (!j || ki < kj) {
-			output.conts.Put(ki, ci.Clone())
+			output.Containers.Put(ki, ci.Clone())
 			i = iiter.Next()
 			ki, ci = iiter.Value()
 		} else if j && (!i || ki > kj) {
 			j = jiter.Next()
 			kj, cj = jiter.Value()
 		} else { // ki == kj
-			output.conts.Put(ki, difference(ci, cj))
+			output.Containers.Put(ki, difference(ci, cj))
 			i, j = iiter.Next(), jiter.Next()
 			ki, ci = iiter.Value()
 			kj, cj = jiter.Value()
@@ -456,22 +451,22 @@ func (b *Bitmap) Difference(other *Bitmap) *Bitmap {
 func (b *Bitmap) Xor(other *Bitmap) *Bitmap {
 	output := NewBitmap()
 
-	iiter, _ := b.conts.Iterator(0)
-	jiter, _ := other.conts.Iterator(0)
+	iiter, _ := b.Containers.Iterator(0)
+	jiter, _ := other.Containers.Iterator(0)
 	i, j := iiter.Next(), jiter.Next()
 	ki, ci := iiter.Value()
 	kj, cj := jiter.Value()
 	for i || j {
 		if i && (!j || ki < kj) {
-			output.conts.Put(ki, ci.Clone())
+			output.Containers.Put(ki, ci.Clone())
 			i = iiter.Next()
 			ki, ci = iiter.Value()
 		} else if j && (!i || ki > kj) {
-			output.conts.Put(kj, cj.Clone())
+			output.Containers.Put(kj, cj.Clone())
 			j = jiter.Next()
 			kj, cj = jiter.Value()
 		} else { // ki == kj
-			output.conts.Put(ki, xor(ci, cj))
+			output.Containers.Put(ki, xor(ci, cj))
 			i, j = iiter.Next(), jiter.Next()
 			ki, ci = iiter.Value()
 			kj, cj = jiter.Value()
@@ -482,17 +477,17 @@ func (b *Bitmap) Xor(other *Bitmap) *Bitmap {
 
 // removeEmptyContainers deletes all containers that have a count of zero.
 func (b *Bitmap) removeEmptyContainers() {
-	citer, _ := b.conts.Iterator(0)
+	citer, _ := b.Containers.Iterator(0)
 	for citer.Next() {
 		k, c := citer.Value()
 		if c.n == 0 {
-			b.conts.Remove(k)
+			b.Containers.Remove(k)
 		}
 	}
 }
 func (b *Bitmap) countEmptyContainers() int {
 	result := 0
-	citer, _ := b.conts.Iterator(0)
+	citer, _ := b.Containers.Iterator(0)
 	for citer.Next() {
 		_, c := citer.Value()
 		if c.n == 0 {
@@ -504,7 +499,7 @@ func (b *Bitmap) countEmptyContainers() int {
 
 // Optimize converts array and bitmap containers to run containers as necessary.
 func (b *Bitmap) Optimize() {
-	citer, _ := b.conts.Iterator(0)
+	citer, _ := b.Containers.Iterator(0)
 	for citer.Next() {
 		_, c := citer.Value()
 		c.Optimize()
@@ -552,7 +547,7 @@ func (b *Bitmap) WriteTo(w io.Writer) (n int64, err error) {
 	// Remove empty containers before persisting.
 	//b.removeEmptyContainers()
 
-	containerCount := b.conts.Size() - b.countEmptyContainers()
+	containerCount := b.Containers.Size() - b.countEmptyContainers()
 	headerSize := headerBaseSize
 	byte2 := make([]byte, 2)
 	byte4 := make([]byte, 4)
@@ -571,7 +566,7 @@ func (b *Bitmap) WriteTo(w io.Writer) (n int64, err error) {
 
 	// Descriptive header section: encode keys and cardinality.
 	// Key and cardinality are stored interleaved here, 12 bytes per container.
-	citer, _ := b.conts.Iterator(0)
+	citer, _ := b.Containers.Iterator(0)
 	for citer.Next() {
 		key, c := citer.Value()
 		// Verify container count before writing.
@@ -589,7 +584,7 @@ func (b *Bitmap) WriteTo(w io.Writer) (n int64, err error) {
 	// Offset header section: write the offset for each container block.
 	// 4 bytes per container.
 	offset := uint32(headerSize + (containerCount * (8 + 2 + 2 + 4)))
-	citer, _ = b.conts.Iterator(0)
+	citer, _ = b.Containers.Iterator(0)
 	for citer.Next() {
 		_, c := citer.Value()
 		if c.n > 0 {
@@ -605,7 +600,7 @@ func (b *Bitmap) WriteTo(w io.Writer) (n int64, err error) {
 	n = int64(headerSize + (containerCount * (8 + 2 + 2 + 4)))
 
 	// Container storage section: write each container block.
-	citer, _ = b.conts.Iterator(0)
+	citer, _ = b.Containers.Iterator(0)
 	for citer.Next() {
 		_, c := citer.Value()
 		if c.n > 0 {
@@ -643,7 +638,7 @@ func (b *Bitmap) UnmarshalBinary(data []byte) error {
 
 	// Descriptive header section: Read container keys and cardinalities.
 	for i, buf := 0, data[headerSize:]; i < int(keyN); i, buf = i+1, buf[12:] {
-		b.conts.PutContainerValues(
+		b.Containers.PutContainerValues(
 			binary.LittleEndian.Uint64(buf[0:8]),
 			byte(binary.LittleEndian.Uint16(buf[8:10])),
 			int(binary.LittleEndian.Uint16(buf[10:12]))+1,
@@ -652,7 +647,7 @@ func (b *Bitmap) UnmarshalBinary(data []byte) error {
 	opsOffset := headerSize + int(keyN)*12
 
 	// Read container offsets and attach data.
-	citer, _ := b.conts.Iterator(0)
+	citer, _ := b.Containers.Iterator(0)
 	for i, buf := 0, data[opsOffset:]; i < int(keyN); i, buf = i+1, buf[4:] {
 		offset := binary.LittleEndian.Uint32(buf[0:4])
 		// Verify the offset is within the bounds of the input data.
@@ -734,10 +729,10 @@ func (b *Bitmap) Iterator() *Iterator {
 func (b *Bitmap) Info() BitmapInfo {
 	info := BitmapInfo{
 		OpN:        b.opN,
-		Containers: make([]ContainerInfo, 0, b.conts.Size()),
+		Containers: make([]ContainerInfo, 0, b.Containers.Size()),
 	}
 
-	citer, _ := b.conts.Iterator(0)
+	citer, _ := b.Containers.Iterator(0)
 	for citer.Next() {
 		k, c := citer.Value()
 		ci := c.info()
@@ -752,7 +747,7 @@ func (b *Bitmap) Check() error {
 	var a ErrorList
 
 	// Check each container.
-	citer, _ := b.conts.Iterator(0)
+	citer, _ := b.Containers.Iterator(0)
 	for citer.Next() {
 		k, c := citer.Value()
 		if err := c.check(); err != nil {
@@ -816,7 +811,7 @@ func (itr *Iterator) Seek(seek uint64) {
 	itr.k = -1
 
 	// Move to the correct container.
-	itr.citer, _ = itr.bitmap.conts.Iterator(highbits(seek))
+	itr.citer, _ = itr.bitmap.Containers.Iterator(highbits(seek))
 	if !itr.citer.Next() {
 		itr.c = nil
 		return // eof
@@ -3282,8 +3277,8 @@ func BitmapsEqual(b, c *Bitmap) error {
 		return errors.New("opNs not equal")
 	}
 
-	biter, _ := b.conts.Iterator(0)
-	citer, _ := c.conts.Iterator(0)
+	biter, _ := b.Containers.Iterator(0)
+	citer, _ := c.Containers.Iterator(0)
 	bn, cn := biter.Next(), citer.Next()
 	for ; bn && cn; bn, cn = biter.Next(), citer.Next() {
 		bk, bc := biter.Value()
diff --git a/roaring/roaring_internal_test.go b/roaring/roaring_internal_test.go
index 8abee4e8e..0202f8b23 100644
--- a/roaring/roaring_internal_test.go
+++ b/roaring/roaring_internal_test.go
@@ -1782,7 +1782,7 @@ func TestDifferenceRunRun(t *testing.T) {
 func TestWriteReadArray(t *testing.T) {
 	ca := &Container{array: []uint16{1, 10, 100, 1000}, n: 4, containerType: ContainerArray}
 	ba := NewBitmap()
-	ba.conts.Put(0, ca)
+	ba.Containers.Put(0, ca)
 	ba2 := NewBitmap()
 	var buf bytes.Buffer
 	_, err := ba.WriteTo(&buf)
@@ -1793,8 +1793,8 @@ func TestWriteReadArray(t *testing.T) {
 	if err != nil {
 		t.Fatalf("error unmarshaling: %v", err)
 	}
-	if !reflect.DeepEqual(ba2.conts.Get(0).array, ca.array) {
-		t.Fatalf("array test expected %x, but got %x", ca.array, ba2.conts.Get(0).array)
+	if !reflect.DeepEqual(ba2.Containers.Get(0).array, ca.array) {
+		t.Fatalf("array test expected %x, but got %x", ca.array, ba2.Containers.Get(0).array)
 	}
 }
 
@@ -1805,7 +1805,7 @@ func TestWriteReadBitmap(t *testing.T) {
 		cb.bitmap[i] = 0x5555555555555555
 	}
 	bb := NewBitmap()
-	bb.conts.Put(0, cb)
+	bb.Containers.Put(0, cb)
 	bb2 := NewBitmap()
 	var buf bytes.Buffer
 	_, err := bb.WriteTo(&buf)
@@ -1816,8 +1816,8 @@ func TestWriteReadBitmap(t *testing.T) {
 	if err != nil {
 		t.Fatalf("error unmarshaling: %v", err)
 	}
-	if !reflect.DeepEqual(bb2.conts.Get(0).bitmap, cb.bitmap) {
-		t.Fatalf("bitmap test expected %x, but got %x", cb.bitmap, bb2.conts.Get(0).bitmap)
+	if !reflect.DeepEqual(bb2.Containers.Get(0).bitmap, cb.bitmap) {
+		t.Fatalf("bitmap test expected %x, but got %x", cb.bitmap, bb2.Containers.Get(0).bitmap)
 	}
 }
 
@@ -1828,7 +1828,7 @@ func TestWriteReadFullBitmap(t *testing.T) {
 		cb.bitmap[i] = 0xffffffffffffffff
 	}
 	bb := NewBitmap()
-	bb.conts.Put(0, cb)
+	bb.Containers.Put(0, cb)
 	bb2 := NewBitmap()
 	var buf bytes.Buffer
 	_, err := bb.WriteTo(&buf)
@@ -1839,22 +1839,22 @@ func TestWriteReadFullBitmap(t *testing.T) {
 	if err != nil {
 		t.Fatalf("error unmarshaling: %v", err)
 	}
-	if !reflect.DeepEqual(bb2.conts.Get(0).bitmap, cb.bitmap) {
-		t.Fatalf("bitmap test expected %x, but got %x", cb.bitmap, bb2.conts.Get(0).bitmap)
+	if !reflect.DeepEqual(bb2.Containers.Get(0).bitmap, cb.bitmap) {
+		t.Fatalf("bitmap test expected %x, but got %x", cb.bitmap, bb2.Containers.Get(0).bitmap)
 	}
 
-	if bb2.conts.Get(0).n != cb.n {
-		t.Fatalf("bitmap test expected count %x, but got %x", cb.n, bb2.conts.Get(0).n)
+	if bb2.Containers.Get(0).n != cb.n {
+		t.Fatalf("bitmap test expected count %x, but got %x", cb.n, bb2.Containers.Get(0).n)
 	}
-	if bb2.conts.Get(0).count() != cb.count() {
-		t.Fatalf("bitmap test expected count %x, but got %x", cb.n, bb2.conts.Get(0).n)
+	if bb2.Containers.Get(0).count() != cb.count() {
+		t.Fatalf("bitmap test expected count %x, but got %x", cb.n, bb2.Containers.Get(0).n)
 	}
 }
 
 func TestWriteReadRun(t *testing.T) {
 	cr := &Container{runs: []interval16{{start: 3, last: 13}, {start: 100, last: 109}}, n: 21, containerType: ContainerRun}
 	br := NewBitmap()
-	br.conts.Put(0, cr)
+	br.Containers.Put(0, cr)
 	br2 := NewBitmap()
 	var buf bytes.Buffer
 	_, err := br.WriteTo(&buf)
@@ -1865,8 +1865,8 @@ func TestWriteReadRun(t *testing.T) {
 	if err != nil {
 		t.Fatalf("error unmarshaling: %v", err)
 	}
-	if !reflect.DeepEqual(br2.conts.Get(0).runs, cr.runs) {
-		t.Fatalf("run test expected %x, but got %x", cr.runs, br2.conts.Get(0).runs)
+	if !reflect.DeepEqual(br2.Containers.Get(0).runs, cr.runs) {
+		t.Fatalf("run test expected %x, but got %x", cr.runs, br2.Containers.Get(0).runs)
 	}
 }
 
@@ -2125,7 +2125,7 @@ func TestXorBitmapRun(t *testing.T) {
 func TestIteratorArray(t *testing.T) {
 	// use values that span two containers
 	b := NewBitmap(0, 1, 10, 100, 1000, 10000, 90000, 100000)
-	if !b.conts.Get(0).isArray() {
+	if !b.Containers.Get(0).isArray() {
 		t.Fatalf("wrong container type")
 	}
 
@@ -2178,7 +2178,7 @@ func TestIteratorBitmap(t *testing.T) {
 	for i := uint64(75000); i < 75100; i++ {
 		b.Add(i)
 	}
-	if !b.conts.Get(0).isBitmap() {
+	if !b.Containers.Get(0).isBitmap() {
 		t.Fatalf("wrong container type")
 	}
 
@@ -2224,7 +2224,7 @@ func TestIteratorBitmap(t *testing.T) {
 func TestIteratorRuns(t *testing.T) {
 	b := NewBitmap(0, 1, 2, 3, 4, 5, 1000, 1001, 1002, 1003, 1004, 1005, 100000, 100001, 100002, 100003, 100004, 100005)
 	b.Optimize()
-	if !b.conts.Get(0).isRun() {
+	if !b.Containers.Get(0).isRun() {
 		t.Fatalf("wrong container type")
 	}
 
diff --git a/server/enterprise.go b/server/enterprise.go
new file mode 100644
index 000000000..41bf89179
--- /dev/null
+++ b/server/enterprise.go
@@ -0,0 +1,13 @@
+// +build enterprise
+
+package server
+
+import (
+	"github.com/pilosa/pilosa/enterprise/b"
+	"github.com/pilosa/pilosa/roaring"
+)
+
+func init() {
+	// Replace Bitmap constructor with B+Tree implementation
+	roaring.NewFileBitmap = b.NewBTreeBitmap
+}