Cook the macaroni in boiling salted water until tender, about 8 to 10 minutes. Drain and rinse under cold water until cool.

While the pasta cooks, hard-boil the eggs: cover with cold water, bring to a boil, then cover, remove from heat, and let sit 10 to 12 minutes. Cool in ice water, peel, and chop.

In a large bowl, whisk together the mayonnaise, mustard, relish, vinegar, salt, and pepper until smooth.

Add the cooled macaroni, celery, onion, and chopped eggs. Fold gently until everything is evenly coated, then cover and refrigerate at least 30 minutes.

Scoop into a serving bowl, sprinkle with paprika, and serve cold.