RuboCop

Brakeman is a security scanner for Ruby on Rails applications. Unlike many web security scanners, Brakeman looks at the source code of your application. This means you do not need to set up your whole application stack to use it. Once Brakeman scans the application code, it produces a report of all security issues it has found. Brakeman requires zero setup or configuration once it is installed. Just run it. Because all Brakeman needs is source code, Brakeman can be run at any stage of development: you can generate a new application with rails new and immediately check it with Brakeman. Since Brakeman does not rely on spidering sites to determine all their pages, it can provide more complete coverage of an application. This includes pages which may not be ‘live’ yet. In theory, Brakeman can find security vulnerabilities before they become exploitable. Brakeman is specifically built for Ruby on Rails applications, so it can easily check configuration settings for best practices.

ESLint is a static code analysis tool for identifying problematic patterns in JavaScript code. It allows developers to configure rules and define custom ones, addressing both code quality and coding style issues. ESLint supports current ECMAScript standards and experimental syntax from future drafts. It can process code using JSX or TypeScript through appropriate plugins or transpilers. The tool is integrated into most text editors and can be part of continuous integration pipelines, enabling automatic problem detection and correction. ESLint is the #1 JavaScript linter by downloads on npm and is used at companies like Microsoft, Airbnb, Netflix, and Facebook. Preprocess code, use custom parsers and write your own rules that work alongside ESLint's built-in rules. Customize ESLint to work exactly the way you need it for your project. Many problems ESLint finds can be automatically fixed. ESLint fixes are syntax-aware so you won't experience errors.