Next.js + React Profiler

Update: You don't need this anymore. In v9.5, Next.js added a --profile flag to enable React Profiler in a production build.

Enable the React Profiler during a production build in your Next.js project

Installation

npm install --save next-plugin-profiler

or

yarn add next-plugin-profiler

Usage with environment variables

Create a next.config.js file:

// next.config.js
const withProfiler = require(`next-plugin-profiler`)({
  isEnabled: process.env.ENABLE_PROFILER === `true`
});

module.exports = withProfiler({});

Then you can run a build command with the environment variable:

ENABLE_PROFILER=true npm run build