This is a webapp that watches your code, linting and blaming all the livelong day. The results show what's ugly and who made it so.
Very much a WIP. It's the evolution of my last two attempts in this realm (a Python and a Go command-line utility).
It currently supports Python (using pep8, pyflakes, and pylint), and Javascript (using JSHint). I plan to steadily add support for more linters and syntaxes.
Disclaimer: I'm not a UI/design guy.