Cook the elbow macaroni according to package directions until al dente, typically 7-9 minutes. Avoid overcooking for best texture.
Drain the pasta thoroughly and rinse under cold running water to stop the cooking process and cool it down quickly.
Transfer the cooled pasta to a large mixing bowl and toss with a small drizzle of olive oil if not using immediately.
Drain the tuna cans completely and flake the tuna into the bowl with the macaroni, breaking up any large chunks.
Add the finely diced celery, minced red onion, and chopped dill pickles to the bowl.
In a small bowl, whisk together the mayonnaise and fresh lemon juice until smooth.
Pour the dressing over the pasta mixture and fold gently with a rubber spatula to evenly coat all ingredients.
Season with salt and freshly ground black pepper to taste.
Cover and refrigerate for at least 30 minutes before serving to allow flavors to meld.
Before serving, taste again and adjust the seasoning if needed. Add any optional ingredients at this stage if desired.
Serve cold as a refreshing side dish or as a satisfying main meal.