In a medium bowl, combine your shrimp with baking soda, kosher salt, and Old Bay seasoning. Toss gently and marinate for 15–20 minutes.

Prepare a large bowl filled with ice water as an ice bath to cool the shrimp after cooking.

Bring 8 cups of water to a rolling boil, adding lemon juice. Drop in brined shrimp and cook for about 90 seconds until opaque. Transfer to ice bath to cool, then drain and pat dry.

In a mixing bowl, combine diced celery, red onion, dill, mayonnaise, Old Bay seasoning, celery seed, lemon juice, and Dijon mustard. Stir until smooth.

Gently fold cooled shrimp into the dressing until well coated without breaking the shrimp.

Cover tightly and chill in the refrigerator for at least 2 hours, preferably overnight.

Before serving, drain excess liquid if needed and serve chilled, garnished with dill, parsley, and lemon wedges.