defaultExt   = ".unknown"
)

// errLimitExceeded error is sent when the maximum limit is reached.
var errLimitExceeded = errors.New("the maximum store limit reached")

// QueueStore - Filestore for persisting items.
type QueueStore[_ any] struct {
	sync.RWMutex
	entryLimit uint64
	directory  string
	fileExt    string

	entries map[string]int64 // key -> modtime as unix nano
}