React 19 Quick Start

This guide covers the React 19 runtime package @autotracer/react19 and the two build-time entry paths that feed it. Call reactTracer() before the first client render, keep browser tracing dormant at startup, and use the Dashboard as the normal runtime control surface in internal browser builds.

AutoTracer exposes component structure, props, and state transitions. Keep the runtime, the build plugin, and the Dashboard out of public-facing builds. A runtime switch is useful for a restricted session, but it is not a security boundary.

Support Floor

React 19.2.0 and ReactDOM 19.2.0, or compatible ^19.2.0 releases.
TypeScript 6 or newer for consumers.
TypeScript 7 for the primary AutoTracer React 19 package build.
The tested Vite integration in this repo uses Vite 8.2.1.

Recommended Browser Workflow

The Dashboard controls tracing, but it does not become a trace viewer. Trace output still goes to the browser's normal logging surface.

Step 1: Install The Packages

For a Vite app:

bash

pnpm add @autotracer/react19 @autotracer/dashboard
pnpm add -D @autotracer/plugin-vite-react19

For a Babel or Next.js App Router app:

bash

pnpm add @autotracer/react19 @autotracer/dashboard
pnpm add -D @autotracer/plugin-babel-react19

Step 2: Initialize The Runtime Before React Renders

The runtime starts dormant by default. In browser apps, keep that default and start tracing only when you are ready to capture one interaction window.

tsx

// src/main.tsx
import { createRoot } from "react-dom/client";

import { App } from "./App.js";

const isInternalBrowserBuild =
  import.meta.env.DEV || import.meta.env.VITE_INTERNAL_QA === "true";

async function renderApplication(): Promise<void> {
  if (isInternalBrowserBuild) {
    const { reactTracer } = await import("@autotracer/react19");

    reactTracer({
      enabled: false,
      outputMode: "copy-paste",
      includeMount: "always",
      includeRendered: "always",
      internalLogLevel: "warn",
    });
  }

  const rootElement = document.getElementById("root");
  if (rootElement === null) {
    throw new Error("Expected the #root element to exist.");
  }

  createRoot(rootElement).render(<App />);
}

void renderApplication();

That startup shape matches the React 19 Vite example apps in this workspace. The important boundary is the placement: reactTracer() runs before createRoot(...).render(...).

Step 3: Add Build-Time Labels

Build-time injection adds useReactTracer() and hook labels so the runtime can report state names such as count instead of just unlabeled values.

For Vite, use React 19 Vite Installation.
For Babel and Next.js App Router, use React 19 Next.js App Router Installation.

Step 4: Start And Stop Tracing

In browser-based internal apps, the Dashboard is the normal control surface.

Mount it through the Vite plugin dashboardConfig path, or with mountDashboard(...) on the Babel path.
Start tracing just before the interaction you care about.
Stop tracing as soon as the capture window is finished.

If the Dashboard is not available, use the lower-level fallback on globalThis.autoTracer:

globalThis.autoTracer.setOutputMode("copy-paste");
globalThis.autoTracer.reactTracer.start();

// Reproduce one interaction.

globalThis.autoTracer.reactTracer.stop();

React 19 Hook Behavior

The React 19 runtime preserves the React 18 public tracing model. useActionState and useOptimistic do not introduce a separate logger format. They use the same generic labelState() path used for existing state hooks.

React 19 Quick Start ​

Support Floor ​

Recommended Browser Workflow ​

Step 1: Install The Packages ​

Step 2: Initialize The Runtime Before React Renders ​

Step 3: Add Build-Time Labels ​

Step 4: Start And Stop Tracing ​

React 19 Hook Behavior ​

Read Next ​