Here’s the thing: We don’t place a particular importance on cover letters or resumes. While sometimes useful, they tend to be overblown and rarely convey a realistic picture. So we leave the choice of upload up to you. Pick one file you think supports your application. If that’s a cover letter, great. If that’s your favorite poem, great. If it’s 1200 lines of code that can take over the world, great. The choice is yours.