diff --git a/reaper/options_test.go b/reaper/options_test.go
new file mode 100644
index 0000000..e48e874
--- /dev/null
+++ b/reaper/options_test.go
@@ -0,0 +1 @@
+package reaper
diff --git a/reaper/reaper_test.go b/reaper/reaper_test.go
new file mode 100644
index 0000000..e48e874
--- /dev/null
+++ b/reaper/reaper_test.go
@@ -0,0 +1 @@
+package reaper
diff --git a/shared/consts.go b/shared/consts.go
index a824751..d68ef02 100644
--- a/shared/consts.go
+++ b/shared/consts.go
@@ -2,9 +2,14 @@ package shared
 
 import "time"
 
+// Defaults for sessions.Options
+const (
+	DefaultPath   = "/"
+	DefaultMaxAge = 60 * 60 * 24 * 30 // 30days
+)
+
 // Defaults for store.Options
 const (
-	DefaultPath       = "/"
 	DefaultBucketName = "sessions"
 )
 
diff --git a/shared/utils.go b/shared/utils.go
index 0401229..7cf7814 100644
--- a/shared/utils.go
+++ b/shared/utils.go
@@ -18,3 +18,9 @@ func Session(data []byte) (protobuf.Session, error) {
 func Expired(session protobuf.Session) bool {
 	return *session.ExpiresAt > 0 && *session.ExpiresAt <= time.Now().Unix()
 }
+
+// NewSession creates and returns a session data.
+func NewSession(values []byte, maxAge int) *protobuf.Session {
+	expiresAt := time.Now().Unix() + int64(maxAge)
+	return &protobuf.Session{Values: values, ExpiresAt: &expiresAt}
+}
diff --git a/shared/utils_test.go b/shared/utils_test.go
index c2b6966..8c7778f 100644
--- a/shared/utils_test.go
+++ b/shared/utils_test.go
@@ -48,3 +48,14 @@ func TestExpired(t *testing.T) {
 		t.Error("Expired() should return false (actual: true)")
 	}
 }
+
+func TestNewSession(t *testing.T) {
+	values := []byte("test")
+	maxAge := 10
+	preExpiresAt := time.Now().Unix() + int64(maxAge)
+	session := NewSession(values, maxAge)
+	postExpiresAt := time.Now().Unix() + int64(maxAge)
+	if string(session.Values) != string(values) || *session.ExpiresAt < preExpiresAt || postExpiresAt < *session.ExpiresAt {
+		t.Errorf("NewSession() returned an invalid value (actual: %+v)", session)
+	}
+}
diff --git a/store/config.go b/store/config.go
index b754ebd..4e52dd4 100644
--- a/store/config.go
+++ b/store/config.go
@@ -16,6 +16,9 @@ func (c *Config) setDefault() {
 	if c.SessionOptions.Path == "" {
 		c.SessionOptions.Path = shared.DefaultPath
 	}
+	if c.SessionOptions.MaxAge == 0 {
+		c.SessionOptions.MaxAge = shared.DefaultMaxAge
+	}
 	if c.DBOptions.BucketName == nil {
 		c.DBOptions.BucketName = []byte(shared.DefaultBucketName)
 	}
diff --git a/store/config_test.go b/store/config_test.go
new file mode 100644
index 0000000..72440ea
--- /dev/null
+++ b/store/config_test.go
@@ -0,0 +1 @@
+package store
diff --git a/store/session.go b/store/session.go
deleted file mode 100644
index c7c0cc8..0000000
--- a/store/session.go
+++ /dev/null
@@ -1,16 +0,0 @@
-package store
-
-import (
-	"time"
-
-	"github.com/yosssi/boltstore/shared/protobuf"
-)
-
-// NewSession creates and returns a session data.
-func NewSession(values []byte, maxAge int) *protobuf.Session {
-	var expiresAt int64
-	if maxAge > 0 {
-		expiresAt = time.Now().Unix() + int64(maxAge)
-	}
-	return &protobuf.Session{Values: values, ExpiresAt: &expiresAt}
-}
diff --git a/store/store.go b/store/store.go
index c600d6e..1783edb 100644
--- a/store/store.go
+++ b/store/store.go
@@ -118,7 +118,7 @@ func (s *Store) save(session *sessions.Session) error {
 	if err != nil {
 		return err
 	}
-	data, err := proto.Marshal(NewSession(buf.Bytes(), session.Options.MaxAge))
+	data, err := proto.Marshal(shared.NewSession(buf.Bytes(), session.Options.MaxAge))
 	if err != nil {
 		return nil
 	}
diff --git a/store/store_test.go b/store/store_test.go
new file mode 100644
index 0000000..72440ea
--- /dev/null
+++ b/store/store_test.go
@@ -0,0 +1 @@
+package store