Cook the pasta according to package instructions until al dente, around 8-10 minutes. Drain and rinse under cold water.

Prepare vegetables by washing and slicing cucumbers, chopping tomatoes, and slicing red onions. Sprinkle cucumbers with salt and let sit for 10 minutes.

Mix the dressing by whisking together mayo or Greek yogurt, vinegar, and sugar in a small bowl until smooth.

Combine cooled pasta with prepared vegetables, add optional shredded carrots, and drizzle dressing over. Toss gently until well combined.

Chill in refrigerator for at least 30 minutes before serving to allow flavors to meld.