diff --git a/file.go b/file.go
index 8973042..944a13b 100644
--- a/file.go
+++ b/file.go
@@ -130,7 +130,6 @@ func (f *File) UnmarshalJSON(b []byte) error {
 		return fmt.Errorf("missing info")
 	}
 
-	fmt.Println(string(info))
 	f.info = &FileInfo{}
 	if err := json.Unmarshal(info, f.info); err != nil {
 		return err
diff --git a/files_map.go b/files_map.go
index 90eb232..eab1ea1 100644
--- a/files_map.go
+++ b/files_map.go
@@ -3,6 +3,7 @@
 package pkger
 
 import (
+	"encoding/json"
 	"sort"
 	"sync"
 )
@@ -12,18 +13,51 @@ import (
 // value: *File
 type filesMap struct {
 	data *sync.Map
-	init sync.Once
 }
 
 func (m *filesMap) Data() *sync.Map {
-	m.init.Do(func() {
-		if m.data == nil {
-			m.data = &sync.Map{}
-		}
-	})
+	if m.data == nil {
+		m.data = &sync.Map{}
+	}
 	return m.data
 }
 
+func (m *filesMap) MarshalJSON() ([]byte, error) {
+	var err error
+	mm := map[string]interface{}{}
+	m.data.Range(func(key, value interface{}) bool {
+		var b []byte
+		b, err = json.Marshal(key)
+		if err != nil {
+			return false
+		}
+		mm[string(b)] = value
+		return true
+	})
+
+	if err != nil {
+		return nil, err
+	}
+
+	return json.Marshal(mm)
+}
+
+func (m *filesMap) UnmarshalJSON(b []byte) error {
+	mm := map[string]*File{}
+
+	if err := json.Unmarshal(b, &mm); err != nil {
+		return err
+	}
+	for k, v := range mm {
+		var pt Path
+		if err := json.Unmarshal([]byte(k), &pt); err != nil {
+			return err
+		}
+		m.Store(pt, v)
+	}
+	return nil
+}
+
 // Delete the key from the map
 func (m *filesMap) Delete(key Path) {
 	m.Data().Delete(key)
diff --git a/index.go b/index.go
index 66ee658..226dae8 100644
--- a/index.go
+++ b/index.go
@@ -68,22 +68,7 @@ func (i *index) Create(pt Path) (*File, error) {
 func (i *index) MarshalJSON() ([]byte, error) {
 	m := map[string]interface{}{}
 
-	fm := map[string]json.RawMessage{}
-
-	var err error
-	i.Files.Range(func(key Path, value *File) bool {
-		b, err := value.MarshalJSON()
-		if err != nil {
-			return false
-		}
-		fm[key.String()] = b
-		return true
-	})
-	if err != nil {
-		return nil, err
-	}
-
-	m["files"] = fm
+	m["files"] = i.Files
 	m["infos"] = i.Infos
 	m["current"] = i.current
 
@@ -99,7 +84,38 @@ func (i *index) MarshalJSON() ([]byte, error) {
 }
 
 func (i *index) UnmarshalJSON(b []byte) error {
-	// fmt.Println(string(b))
+	m := map[string]json.RawMessage{}
+
+	if err := json.Unmarshal(b, &m); err != nil {
+		return err
+	}
+
+	infos, ok := m["infos"]
+	if !ok {
+		return fmt.Errorf("missing infos")
+	}
+	i.Infos = &infosMap{}
+	if err := json.Unmarshal(infos, i.Infos); err != nil {
+		return err
+	}
+
+	files, ok := m["files"]
+	if !ok {
+		return fmt.Errorf("missing files")
+	}
+
+	i.Files = &filesMap{}
+	if err := json.Unmarshal(files, i.Files); err != nil {
+		return err
+	}
+
+	current, ok := m["current"]
+	if !ok {
+		return fmt.Errorf("missing current")
+	}
+	if err := json.Unmarshal(current, &i.current); err != nil {
+		return err
+	}
 	return nil
 }
 
diff --git a/index_test.go b/index_test.go
index 0286b12..574e48c 100644
--- a/index_test.go
+++ b/index_test.go
@@ -1,6 +1,8 @@
 package pkger
 
 import (
+	"encoding/json"
+	"fmt"
 	"io"
 	"os"
 	"strings"
@@ -61,3 +63,42 @@ func Test_index_Create_Write(t *testing.T) {
 	r.NotZero(fi.ModTime())
 	r.NotEqual(mt, fi.ModTime())
 }
+
+func Test_index_JSON(t *testing.T) {
+	r := require.New(t)
+
+	i := newIndex()
+
+	f, err := i.Create(Path{
+		Name: "/radio.radio",
+	})
+	r.NoError(err)
+	r.NotNil(f)
+	fmt.Fprint(f, radio)
+	r.NoError(f.Close())
+
+	c, err := i.Current()
+	r.NoError(err)
+	r.Equal(curPkg, c.ImportPath)
+
+	_, err = i.Info("github.com/markbates/hepa")
+	r.NoError(err)
+
+	r.Equal(1, len(i.Files.Keys()))
+	r.Equal(1, len(i.Infos.Keys()))
+	r.NotZero(i.current)
+
+	jason, err := json.Marshal(i)
+	r.NoError(err)
+	r.NotZero(jason)
+
+	i2 := &index{}
+
+	r.NoError(json.Unmarshal(jason, i2))
+
+	r.NotNil(i2.Infos)
+	r.NotNil(i2.Files)
+	r.NotZero(i2.current)
+	r.Equal(1, len(i2.Files.Keys()))
+	r.Equal(1, len(i2.Infos.Keys()))
+}
diff --git a/infos_map.go b/infos_map.go
index ce3b576..3af414f 100644
--- a/infos_map.go
+++ b/infos_map.go
@@ -3,6 +3,8 @@
 package pkger
 
 import (
+	"encoding/json"
+	"fmt"
 	"sort"
 	"sync"
 
@@ -26,6 +28,27 @@ func (m *infosMap) Data() *sync.Map {
 	return m.data
 }
 
+func (m *infosMap) MarshalJSON() ([]byte, error) {
+	mm := map[string]interface{}{}
+	m.data.Range(func(key, value interface{}) bool {
+		mm[fmt.Sprintf("%s", key)] = value
+		return true
+	})
+	return json.Marshal(mm)
+}
+
+func (m *infosMap) UnmarshalJSON(b []byte) error {
+	mm := map[string]here.Info{}
+
+	if err := json.Unmarshal(b, &mm); err != nil {
+		return err
+	}
+	for k, v := range mm {
+		m.Store(k, v)
+	}
+	return nil
+}
+
 // Delete the key from the map
 func (m *infosMap) Delete(key string) {
 	m.Data().Delete(key)
diff --git a/parse_test.go b/parse_test.go
index 30b6673..d0d089d 100644
--- a/parse_test.go
+++ b/parse_test.go
@@ -6,8 +6,6 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-const curPkg = "github.com/markbates/pkger"
-
 func Test_Parse_Happy(t *testing.T) {
 	table := []struct {
 		in  string
diff --git a/pkger_test.go b/pkger_test.go
index 5d7b877..ba597c7 100644
--- a/pkger_test.go
+++ b/pkger_test.go
@@ -5,6 +5,8 @@ import (
 	"strings"
 )
 
+const curPkg = "github.com/markbates/pkger"
+
 func createFile(p string, body ...string) (*File, error) {
 	if len(body) == 0 {
 		body = append(body, radio)