err := w.WriteHeader(&Header{
		Name: "lorem.txt",
		Mode: 0600,
		Size: int64(len(inp)),
	})
	if err != nil {
		f.Fatalf("failed to create writer: %s", err)
	}
	_, err = w.Write(inp)

// Only changing meaning of fields requires a version bump.
// bucketMetadataFormat refers to the format.
// bucketMetadataVersion can be used to track a rolling upgrade of a field.
type BucketMetadata struct {
	Name                        string
	Created                     time.Time
	LockEnabled                 bool // legacy not used anymore.
	PolicyConfigJSON            []byte