Peel and devein the shrimp
Rinse the shrimp under cold water
Chop the shrimp into small pieces
Place the shrimp in a glass or nonreactive bowl
Cover the shrimp with fresh lime juice
Refrigerate until the shrimp turns opaque and firm
Drain off excess lime juice
Add diced tomatoes, onion, cucumber, cilantro, and jalapeño
Season with salt and pepper
Mix gently to combine
Chill before serving
Serve with tostadas, tortilla chips, or crackers