React upgrades

Upgrade React apps with real codemods and real builds

Q: Does UpgradePilot invent codemod names?

No. Transform names are matched against the real react-codemod repository and release notes; an invented name would simply fail, so none are guessed.

Q: Does it support Vite, CRA or custom builds?

It runs your project’s own npm run build, so whatever your build script does is what gets validated.

Quick answer. UpgradePilot upgrades React apps by deriving versions from npm outdated, verifying them with a real npm install, running the official react-codemod transforms selected from React’s own release notes, and validating with npm run build and your Jest or Vitest tests.

The problem

React upgrades touch dependencies, deprecated APIs and sometimes build tooling, and each library in your tree has its own compatibility story.

Hallucinated codemod names or package versions waste hours; the fix is to use the real tools and check their output.

What UpgradePilot does for React

Detects React and its tooling from package.json.
Derives target versions from npm outdated and verifies the install with npm install.
Selects react-codemod transforms by matching React’s real release notes.
Validates with npm run build and parses Jest or Vitest results.
Documents the changes and opens a pull request.

What you still review by hand

UpgradePilot is built so nothing is hidden: these are the places a person should look before merging.

Third-party component libraries that have not published React-compatible releases.
Behavioral changes in rendering, effects or concurrent features that unit tests may not exercise.
Type definition and lint-rule changes introduced by newer tooling.
Visual regressions — run your end-to-end or visual tests before merging.

Common pitfalls

Peer-dependency conflicts are the most common blocker; read the install output in the pull request.
Codemods change code mechanically — review the diff, don’t just trust a green build.

Documentation to review

Read the official notes for the versions you’re crossing alongside the pull request UpgradePilot produces.

Official documentationReact blog (release posts)Release announcements and upgrade guides.Official documentationReact 19 upgrade guideBreaking changes and migration steps for React 19.Official documentationreact-codemodThe official codemod collection UpgradePilot runs.Official documentationReact changelogEvery change per release.UpgradePilotAgent architectureReact/Next.js Codemods, Build Validation and Test Runner agents.

React upgrade FAQ

Does UpgradePilot invent codemod names?

No. Transform names are matched against the real react-codemod repository and release notes; an invented name would simply fail, so none are guessed.

Which test runners are parsed?

Jest and Vitest.

Does it support Vite, CRA or custom builds?

It runs your project’s own npm run build, so whatever your build script does is what gets validated.