Agent skill · software engineering · github
react19-source-patterns
Reference for React 19 source-file migration patterns, including API changes, ref handling, and context updates.
Why this skill is useful
Provides specific migration patterns and API changes for React 19 that the AI wouldn't reliably generate on its own.
What it needs
About 1k tokens when loaded. Last updated 2026-08-07. 37,534 stars on the source repository.
What this skill does
React 19 Source Migration Patterns Reference for every source-file migration required for React 19. Quick Reference Table Pattern Action Reference --- --- --- ReactDOM.render(...) → createRoot().render() See references/api-migrations.md ReactDOM.hydrate(...) → hydrateRoot(...) See references/api-migrations.md unmountComponentAtNode → root.unmount() Inline fix ReactDOM.findDOMNode → direct ref Inline fix forwardRef(...) wrapper → ref as direct prop See references/api-migrations.md Component.defaultProps = {} → ES6 default params See references/api-migrations.md useRef() no arg → useRef(null) Inline fix add null Legacy Context → createContext → api-migrations.md#legacy-context String refs this.refs.x → createRef() → api-migrations.md#string-refs import React from 'react' (unused) Remove Only if no React. usage in file PropTypes Rule Do not remove .propTypes assignments. The prop-types package still works as a standalone validator. React 19 only removes the built-in runtime checking from the React package the package itself remains valid. Add this comment above any .propTypes block: Read the Reference For full before/after code for each migration, read references/api-migrations.md. It contains the complete patterns including edge cases for forwardRef with useImperativeHandle, defaultProps null vs undefined behavior, and legacy context provider/consumer cross-file migrations.
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills github/react19-source-patterns