Bring a large pot of salted water to a boil. Cook pasta according to package directions.

While pasta is cooking, heat the olive oil in a cast-iron skillet over medium-high heat. When shimmering, add the walnuts and cook until beginning to toast, about 4 minutes. Add the olives and minced garlic. Remove from heat while pasta finishes cooking.

When pasta is cooked, use tongs to place the cooked bucatini directly into walnut mixture. Add the lemon juice and rind. Warm over medium heat. Toss until all the elements are evenly incorporated. Season to taste with salt and pepper.