diff --git a/src/instance.go b/src/instance.go
index 1d3a26f..0741ca0 100644
--- a/src/instance.go
+++ b/src/instance.go
@@ -22,7 +22,7 @@ type Instance struct {
 	ThemeDir        string
 	AttemptInterval time.Duration
 
-	categories       map[string]*Mothball
+	categories       map[string]*Zipfs
 	update           chan bool
 	jPuzzleList      []byte
 	jPointsLog       []byte
@@ -41,7 +41,7 @@ func (ctx *Instance) Initialize() error {
 	}
 
 	ctx.Base = strings.TrimRight(ctx.Base, "/")
-	ctx.categories = map[string]*Mothball{}
+	ctx.categories = map[string]*Zipfs{}
 	ctx.update = make(chan bool, 10)
 	ctx.nextAttempt = map[string]time.Time{}
 	ctx.nextAttemptMutex = new(sync.RWMutex)
diff --git a/src/maintenance.go b/src/maintenance.go
index abd51e0..751271b 100644
--- a/src/maintenance.go
+++ b/src/maintenance.go
@@ -148,7 +148,7 @@ func (ctx *Instance) tidy() {
 		categoryName := strings.TrimSuffix(filename, ".mb")
 
 		if _, ok := ctx.categories[categoryName]; !ok {
-			mb, err := OpenMothball(filepath)
+			mb, err := OpenZipfs(filepath)
 			if err != nil {
 				log.Printf("Error opening %s: %s", filepath, err)
 				continue
diff --git a/src/mothball.go b/src/mothball.go
deleted file mode 100644
index 149dbf5..0000000
--- a/src/mothball.go
+++ /dev/null
@@ -1,191 +0,0 @@
-package main
-
-import (
-	"archive/zip"
-	"fmt"
-	"io"
-	"io/ioutil"
-	"os"
-	"strings"
-	"time"
-)
-
-type Mothball struct {
-	zf       *zip.ReadCloser
-	filename string
-	mtime    time.Time
-}
-
-type MothballFile struct {
-	f   io.ReadCloser
-	pos int64
-	zf  *zip.File
-	io.Reader
-	io.Seeker
-	io.Closer
-}
-
-func NewMothballFile(zf *zip.File) (*MothballFile, error) {
-	mf := &MothballFile{
-		zf:  zf,
-		pos: 0,
-		f:   nil,
-	}
-	if err := mf.reopen(); err != nil {
-		return nil, err
-	}
-	return mf, nil
-}
-
-func (mf *MothballFile) reopen() error {
-	if mf.f != nil {
-		if err := mf.f.Close(); err != nil {
-			return err
-		}
-	}
-	f, err := mf.zf.Open()
-	if err != nil {
-		return err
-	}
-	mf.f = f
-	mf.pos = 0
-	return nil
-}
-
-func (mf *MothballFile) ModTime() time.Time {
-	return mf.zf.Modified
-}
-
-func (mf *MothballFile) Read(p []byte) (int, error) {
-	n, err := mf.f.Read(p)
-	mf.pos += int64(n)
-	return n, err
-}
-
-func (mf *MothballFile) Seek(offset int64, whence int) (int64, error) {
-	var pos int64
-	switch whence {
-	case io.SeekStart:
-		pos = offset
-	case io.SeekCurrent:
-		pos = mf.pos + int64(offset)
-	case io.SeekEnd:
-		pos = int64(mf.zf.UncompressedSize64) - int64(offset)
-	}
-
-	if pos < 0 {
-		return mf.pos, fmt.Errorf("Tried to seek %d before start of file", pos)
-	}
-	if pos >= int64(mf.zf.UncompressedSize64) {
-		// We don't need to decompress anything, we're at the end of the file
-		mf.f.Close()
-		mf.f = ioutil.NopCloser(strings.NewReader(""))
-		mf.pos = int64(mf.zf.UncompressedSize64)
-		return mf.pos, nil
-	}
-	if pos < mf.pos {
-		if err := mf.reopen(); err != nil {
-			return mf.pos, err
-		}
-	}
-
-	buf := make([]byte, 32*1024)
-	for pos > mf.pos {
-		l := pos - mf.pos
-		if l > int64(cap(buf)) {
-			l = int64(cap(buf)) - 1
-		}
-		p := buf[0:int(l)]
-		n, err := mf.Read(p)
-		if err != nil {
-			return mf.pos, err
-		} else if n <= 0 {
-			return mf.pos, fmt.Errorf("Short read (%d bytes)", n)
-		}
-	}
-
-	return mf.pos, nil
-}
-
-func (mf *MothballFile) Close() error {
-	return mf.f.Close()
-}
-
-func OpenMothball(filename string) (*Mothball, error) {
-	var m Mothball
-
-	m.filename = filename
-
-	err := m.Refresh()
-	if err != nil {
-		return nil, err
-	}
-
-	return &m, nil
-}
-
-func (m *Mothball) Close() error {
-	return m.zf.Close()
-}
-
-func (m *Mothball) Refresh() error {
-	info, err := os.Stat(m.filename)
-	if err != nil {
-		return err
-	}
-	mtime := info.ModTime()
-
-	if !mtime.After(m.mtime) {
-		return nil
-	}
-
-	zf, err := zip.OpenReader(m.filename)
-	if err != nil {
-		return err
-	}
-
-	if m.zf != nil {
-		m.zf.Close()
-	}
-	m.zf = zf
-	m.mtime = mtime
-
-	return nil
-}
-
-func (m *Mothball) get(filename string) (*zip.File, error) {
-	for _, f := range m.zf.File {
-		if filename == f.Name {
-			return f, nil
-		}
-	}
-	return nil, fmt.Errorf("File not found: %s %s", m.filename, filename)
-}
-
-func (m *Mothball) Header(filename string) (*zip.FileHeader, error) {
-	f, err := m.get(filename)
-	if err != nil {
-		return nil, err
-	}
-	return &f.FileHeader, nil
-}
-
-func (m *Mothball) Open(filename string) (*MothballFile, error) {
-	f, err := m.get(filename)
-	if err != nil {
-		return nil, err
-	}
-	mf, err := NewMothballFile(f)
-	return mf, err
-}
-
-func (m *Mothball) ReadFile(filename string) ([]byte, error) {
-	f, err := m.Open(filename)
-	if err != nil {
-		return nil, err
-	}
-	defer f.Close()
-
-	bytes, err := ioutil.ReadAll(f)
-	return bytes, err
-}
diff --git a/src/zipfs.go b/src/zipfs.go
new file mode 100644
index 0000000..1b0f00a
--- /dev/null
+++ b/src/zipfs.go
@@ -0,0 +1,191 @@
+package main
+
+import (
+	"archive/zip"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"strings"
+	"time"
+)
+
+type Zipfs struct {
+	zf       *zip.ReadCloser
+	filename string
+	mtime    time.Time
+}
+
+type ZipfsFile struct {
+	f   io.ReadCloser
+	pos int64
+	zf  *zip.File
+	io.Reader
+	io.Seeker
+	io.Closer
+}
+
+func NewZipfsFile(zf *zip.File) (*ZipfsFile, error) {
+	zfsf := &ZipfsFile{
+		zf:  zf,
+		pos: 0,
+		f:   nil,
+	}
+	if err := zfsf.reopen(); err != nil {
+		return nil, err
+	}
+	return zfsf, nil
+}
+
+func (zfsf *ZipfsFile) reopen() error {
+	if zfsf.f != nil {
+		if err := zfsf.f.Close(); err != nil {
+			return err
+		}
+	}
+	f, err := zfsf.zf.Open()
+	if err != nil {
+		return err
+	}
+	zfsf.f = f
+	zfsf.pos = 0
+	return nil
+}
+
+func (zfsf *ZipfsFile) ModTime() time.Time {
+	return zfsf.zf.Modified
+}
+
+func (zfsf *ZipfsFile) Read(p []byte) (int, error) {
+	n, err := zfsf.f.Read(p)
+	zfsf.pos += int64(n)
+	return n, err
+}
+
+func (zfsf *ZipfsFile) Seek(offset int64, whence int) (int64, error) {
+	var pos int64
+	switch whence {
+	case io.SeekStart:
+		pos = offset
+	case io.SeekCurrent:
+		pos = zfsf.pos + int64(offset)
+	case io.SeekEnd:
+		pos = int64(zfsf.zf.UncompressedSize64) - int64(offset)
+	}
+
+	if pos < 0 {
+		return zfsf.pos, fmt.Errorf("Tried to seek %d before start of file", pos)
+	}
+	if pos >= int64(zfsf.zf.UncompressedSize64) {
+		// We don't need to decompress anything, we're at the end of the file
+		zfsf.f.Close()
+		zfsf.f = ioutil.NopCloser(strings.NewReader(""))
+		zfsf.pos = int64(zfsf.zf.UncompressedSize64)
+		return zfsf.pos, nil
+	}
+	if pos < zfsf.pos {
+		if err := zfsf.reopen(); err != nil {
+			return zfsf.pos, err
+		}
+	}
+
+	buf := make([]byte, 32*1024)
+	for pos > zfsf.pos {
+		l := pos - zfsf.pos
+		if l > int64(cap(buf)) {
+			l = int64(cap(buf)) - 1
+		}
+		p := buf[0:int(l)]
+		n, err := zfsf.Read(p)
+		if err != nil {
+			return zfsf.pos, err
+		} else if n <= 0 {
+			return zfsf.pos, fmt.Errorf("Short read (%d bytes)", n)
+		}
+	}
+
+	return zfsf.pos, nil
+}
+
+func (zfsf *ZipfsFile) Close() error {
+	return zfsf.f.Close()
+}
+
+func OpenZipfs(filename string) (*Zipfs, error) {
+	var zfs Zipfs
+
+	zfs.filename = filename
+
+	err := zfs.Refresh()
+	if err != nil {
+		return nil, err
+	}
+
+	return &zfs, nil
+}
+
+func (zfs *Zipfs) Close() error {
+	return zfs.zf.Close()
+}
+
+func (zfs *Zipfs) Refresh() error {
+	info, err := os.Stat(zfs.filename)
+	if err != nil {
+		return err
+	}
+	mtime := info.ModTime()
+
+	if !mtime.After(zfs.mtime) {
+		return nil
+	}
+
+	zf, err := zip.OpenReader(zfs.filename)
+	if err != nil {
+		return err
+	}
+
+	if zfs.zf != nil {
+		zfs.zf.Close()
+	}
+	zfs.zf = zf
+	zfs.mtime = mtime
+
+	return nil
+}
+
+func (zfs *Zipfs) get(filename string) (*zip.File, error) {
+	for _, f := range zfs.zf.File {
+		if filename == f.Name {
+			return f, nil
+		}
+	}
+	return nil, fmt.Errorf("File not found: %s %s", zfs.filename, filename)
+}
+
+func (zfs *Zipfs) Header(filename string) (*zip.FileHeader, error) {
+	f, err := zfs.get(filename)
+	if err != nil {
+		return nil, err
+	}
+	return &f.FileHeader, nil
+}
+
+func (zfs *Zipfs) Open(filename string) (*ZipfsFile, error) {
+	f, err := zfs.get(filename)
+	if err != nil {
+		return nil, err
+	}
+	zfsf, err := NewZipfsFile(f)
+	return zfsf, err
+}
+
+func (zfs *Zipfs) ReadFile(filename string) ([]byte, error) {
+	f, err := zfs.Open(filename)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	bytes, err := ioutil.ReadAll(f)
+	return bytes, err
+}
diff --git a/src/mothball_test.go b/src/zipfs_test.go
similarity index 87%
rename from src/mothball_test.go
rename to src/zipfs_test.go
index 8115809..22d9386 100644
--- a/src/mothball_test.go
+++ b/src/zipfs_test.go
@@ -9,8 +9,8 @@ import (
 	"testing"
 )
 
-func TestMothball(t *testing.T) {
-	tf, err := ioutil.TempFile("", "mothball")
+func TestZipfs(t *testing.T) {
+	tf, err := ioutil.TempFile("", "zipfs")
 	if err != nil {
 		t.Error(err)
 		return
@@ -35,7 +35,7 @@ func TestMothball(t *testing.T) {
 	tf.Close()
 
 	// Now read it in
-	mb, err := OpenMothball(tf.Name())
+	mb, err := OpenZipfs(tf.Name())
 	if err != nil {
 		t.Error(err)
 		return