diff --git a/cmd/tusd/cli/composer.go b/cmd/tusd/cli/composer.go
index a3c17d8..f8c64ce 100644
--- a/cmd/tusd/cli/composer.go
+++ b/cmd/tusd/cli/composer.go
@@ -55,7 +55,8 @@ func CreateComposer() {
 
 		stdout.Printf("Using 'gcs://%s' as GCS bucket for storage.\n", Flags.GCSBucket)
 
-		store := gcsstore.New(Flags.GCSBucket, Flags.GCSObjectPrefix, service)
+		store := gcsstore.New(Flags.GCSBucket, service)
+		store.ObjectPrefix = Flags.GCSObjectPrefix
 		store.UseIn(Composer)
 
 		locker := memorylocker.New()
diff --git a/gcsstore/gcsstore.go b/gcsstore/gcsstore.go
index 9171376..ada3881 100644
--- a/gcsstore/gcsstore.go
+++ b/gcsstore/gcsstore.go
@@ -45,10 +45,9 @@ type GCSStore struct {
 
 // New constructs a new GCS storage backend using the supplied GCS bucket name
 // and service object.
-func New(bucket string, objPrefix string, service GCSAPI) GCSStore {
+func New(bucket string, service GCSAPI) GCSStore {
 	return GCSStore{
 		Bucket:       bucket,
-		ObjectPrefix: objPrefix,
 		Service:      service,
 	}
 }
diff --git a/gcsstore/gcsstore_test.go b/gcsstore/gcsstore_test.go
index cf7dc60..bd66e4f 100644
--- a/gcsstore/gcsstore_test.go
+++ b/gcsstore/gcsstore_test.go
@@ -20,7 +20,6 @@ import (
 
 const mockID = "123456789abcdefghijklmnopqrstuvwxyz"
 const mockBucket = "bucket"
-const mockObjPrefix = ""
 const mockSize = 1337
 const mockReaderData = "helloworld"
 
@@ -44,7 +43,7 @@ func TestNewUpload(t *testing.T) {
 	assert := assert.New(t)
 
 	service := NewMockGCSAPI(mockCtrl)
-	store := gcsstore.New(mockBucket, mockObjPrefix, service)
+	store := gcsstore.New(mockBucket, service)
 
 	assert.Equal(store.Bucket, mockBucket)
 
@@ -95,7 +94,7 @@ func TestGetInfo(t *testing.T) {
 	assert := assert.New(t)
 
 	service := NewMockGCSAPI(mockCtrl)
-	store := gcsstore.New(mockBucket, mockObjPrefix, service)
+	store := gcsstore.New(mockBucket, service)
 
 	assert.Equal(store.Bucket, mockBucket)
 
@@ -158,7 +157,7 @@ func TestGetInfoNotFound(t *testing.T) {
 	assert := assert.New(t)
 
 	service := NewMockGCSAPI(mockCtrl)
-	store := gcsstore.New(mockBucket, mockObjPrefix, service)
+	store := gcsstore.New(mockBucket, service)
 
 	params := gcsstore.GCSObjectParams{
 		Bucket: store.Bucket,
@@ -203,7 +202,7 @@ func TestGetReader(t *testing.T) {
 	assert := assert.New(t)
 
 	service := NewMockGCSAPI(mockCtrl)
-	store := gcsstore.New(mockBucket, mockObjPrefix, service)
+	store := gcsstore.New(mockBucket, service)
 
 	assert.Equal(store.Bucket, mockBucket)
 
@@ -232,7 +231,7 @@ func TestTerminate(t *testing.T) {
 	assert := assert.New(t)
 
 	service := NewMockGCSAPI(mockCtrl)
-	store := gcsstore.New(mockBucket, mockObjPrefix, service)
+	store := gcsstore.New(mockBucket, service)
 
 	assert.Equal(store.Bucket, mockBucket)
 
@@ -254,7 +253,7 @@ func TestFinishUpload(t *testing.T) {
 	assert := assert.New(t)
 
 	service := NewMockGCSAPI(mockCtrl)
-	store := gcsstore.New(mockBucket, mockObjPrefix, service)
+	store := gcsstore.New(mockBucket, service)
 
 	assert.Equal(store.Bucket, mockBucket)
 
@@ -373,7 +372,7 @@ func TestWriteChunk(t *testing.T) {
 	assert := assert.New(t)
 
 	service := NewMockGCSAPI(mockCtrl)
-	store := gcsstore.New(mockBucket, mockObjPrefix, service)
+	store := gcsstore.New(mockBucket, service)
 
 	assert.Equal(store.Bucket, mockBucket)