HTMLProofer
Test your rendered HTML files to make sure they're accurate.
HTMLProofer is a set of tests to validate your HTML output. These tests check if your image references are legitimate, if they have alt tags, if your internal links are working, and so on. It's intended to be an all-in-one checker for your output. In scope for this project is any well-known and widely-used test for HTML document quality. A major use for this project is continuous integration -- so we must have reliable results. We usually balance correctness over performance. And, if necessary...