localhost:3000/posts/ssr-ssg or localhost:3000/posts/pre-rendering. pages/posts/[id].js and lib/posts.js match the files in the next-learn repo (https://github.com/vercel/next-learn/blob/master/basics/dynamic-routes-step-1/), as suggested by the tutorial's troubleshooting section, but it's still not working. I'm not sure if it's an issue with getStaticPaths() or getStaticProps() in the pages/posts/[id].js file.