ESLint — JavaScript and TypeScript Linting ESLint reads your source code, applies a set of rules, and reports problems ranging from stylistic inconsistencies to genuine bugs. It catches unused variables, missing return statements, inconsistent naming, accessibility violations, and hundreds of other issues that slip past even careful code review. This skill covers ESLint 9+ with the modern flat config format. If you're starting a new project or migrating from the legacy format, flat config is the way forward. Installing ESLint ESLint 9 ships as a single package. TypeScript and React support co…