diff --git a/bitcask.go b/bitcask.go
index 72bd560..b1f27c5 100644
--- a/bitcask.go
+++ b/bitcask.go
@@ -354,7 +354,7 @@ func Open(path string, options ...option) (*Bitcask, error) {
 
 	bitcask := &Bitcask{
 		Flock:     flock.New(filepath.Join(path, "lock")),
-		config:    NewDefaultConfig(),
+		config:    newDefaultConfig(),
 		path:      path,
 		curr:      curr,
 		keydir:    keydir,
diff --git a/options.go b/options.go
index 497c823..0153676 100644
--- a/options.go
+++ b/options.go
@@ -17,7 +17,7 @@ type config struct {
 	MaxValueSize    int
 }
 
-func NewDefaultConfig() *config {
+func newDefaultConfig() *config {
 	return &config{
 		MaxDatafileSize: DefaultMaxDatafileSize,
 		MaxKeySize:      DefaultMaxKeySize,