A Ruby static code analyzer and formatter, based on the community Ruby style guide.

Checkstyle is a development tool to help programmers write Java code that adheres to a coding standard. By default it supports the Google Java Style Guide and Sun Code Conventions, but is highly configurable. It can be invoked with an ANT task and a command line program.

The uncompromising Python code formatter

flake8 is a python tool that glues together pycodestyle, pyflakes, mccabe, and third-party plugins to check the style and quality of some python code.

Simple Python style checker in one Python file

Automated linting of Cascading Stylesheets

Nu Html Checker – Helps you catch problems in your HTML/CSS/SVG

⚙️ The static code analysis tool you need for your HTML

Configurable tool for writing clean, consistent SCSS

CSS coding style formatter