Integer compositions of n can be viewed as bargraphs, in which the ith part of the composition x_i is given by the ith column of the bargraph with x_i cells. The sun is at infinity in the northwest of our two-dimensional model, and each composition casts a shadow in accordance with the rules of physics. We find the number of unit squares in this shadow (but not being part of the composition) through a bivariate generating function tracking composition size and shadow.