ESLint v10.0.0 introduces breaking changes requiring Node.js v20.19+, v22.13+, or v24+. The old eslintrc configuration format is no longer supported; users must migrate to eslint.config.js. Configuration file lookup now starts from each linted file's directory rather than the current working directory. JSX references are now properly tracked for scope analysis. The eslint:recommended preset enables three new rules. Several deprecated APIs, methods, and rule options have been removed, including context methods like getCwd() and getSourceCode(), and SourceCode methods like getJSDocComment(). The stylish formatter now uses Node.js's native styleText instead of chalk. Plugin developers must update custom rules to use property-based context members and handle JSX identifiers in scope analysis.