Agent skill · software engineering · github
react18-legacy-context
Provides the complete migration pattern for React legacy context API (contextTypes, childContextTypes, getChildContext) to the modern createContext API. Use this skill whenever migrating legacy context in class components - this is always a cross-file migration requiring the provider AND all consumers to be updated together. Use it before touching any contextTypes or childContextTypes code, because migrating only the provider without the consumers (or vice versa) will cause a runtime failure. Always read this skill before writing any context migration - the cross-file coordination steps here prevent the most common context migration bugs.
Why this skill is useful
Provides a detailed migration pattern and specific commands for transitioning from legacy context to modern context in React, which 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 18 Legacy Context Migration Legacy context (contextTypes, childContextTypes, getChildContext) was deprecated in React 16.3 and warns in React 18.3.1. It is removed in React 19. This Is Always a Cross-File Migration Unlike most other migrations that touch one file at a time, context migration requires coordinating: 1. Create the context object (usually a new file) 2. Update the provider component 3. Update every consumer component Missing any consumer leaves the app broken - it will read from the wrong context or get undefined. Migration Steps (Always Follow This Order) Scan Commands Reference Files references/single-context.md - complete migration for one context (theme, auth, etc.) with provider + class consumer + function consumer references/multi-context.md - apps with multiple legacy contexts (nested providers, multiple consumers of different contexts) references/context-file-template.md - the standard file structure for a new context module
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills github/react18-legacy-context