In a medium saucepan, bring water to a boil; stir in couscous. Immediately remove pot from the heat, cover and set aside for 10 minutes. Uncover, transfer couscous to a large bowl and fluff with a fork; set aside to let cool to room temperature.
Add arugula, tomatoes, lemon juice, oil, zest, pepper flakes, salami, basil and salt and toss gently to combine. Serve salad at room temperature.