setup-react

React 19.1 + Vite 7.1 Application Setup

Build and run a React 19.1 sendmoney proof-of-concept application with Vite 7.1.

Prerequisites

• Node.js 18+ installed
• npm available on PATH

Instructions

The reference application is a mobile-responsive sendmoney app located in references/.

1. Install dependencies

npm install

2. Start the development server

npm run dev

The app will start on http://localhost:5173 by default.

3. Build for production

npm run build
npm run preview

Reference Files

Key files in references/:

• package.json — Dependencies including React 19.1, Vite 7.1
• vite.config.js — Vite configuration with React plugin
• src/main.jsx — Application entry point
• src/App.jsx — Main application component
• src/components/ — SendMoneyForm, PayeesList, AddPayeeModal, ResultPage, ScamAlertModal
• src/services/mockApi.js — Mock API for transaction simulation
• src/hooks/useFeatureFlag.js — Custom hook for feature flag integration
• src/datadog-rum.js — Datadog RUM initialization
• src/datadog-feature-flags.js — Datadog Feature Flags configuration

Validation

# Install and start dev server
npm install && npm run dev

# Verify the app loads at http://localhost:5173
# Verify the sendmoney form renders
# Verify mock API endpoints respond (transaction submission)

• App loads without console errors
• SendMoney form is interactive
• Transaction flow completes end-to-end with mock API

Troubleshooting

npm install fails

Cause: Node.js version too old or network issue. Fix: Ensure Node.js 18+ is installed (node --version). Clear npm cache with npm cache clean --force.

Vite dev server fails to start

Cause: Port 5173 already in use or missing dependencies. Fix: Kill the process on port 5173 or run with --port 3000. Re-run npm install.

Blank page in browser

Cause: Build error or missing React plugin. Fix: Check terminal for errors. Ensure @vitejs/plugin-react is in devDependencies.