esbuild-plugin-babel VS esbuild-rails

As mentioned the frameworks have gone through some changes since then. Babel is hardly ever used these days, esbuild doesn't pick up the babel config automatically. If you're using the default esbuild config generated with a modern phx_new version, look into changing it to a custom build script in https://hexdocs.pm/phoenix/asset_management.html#esbuild-plugins and then integrate something like this plugin https://github.com/nativew/esbuild-plugin-babel to be able to run https://github.com/mAAdhaTTah/babel-plugin-prismjs. There is a comment at the bottom of the tutorial of someone getting it to work with live view by listening for a phx page loading event, but the more idiomatic way these days would be to use a hook.

// config/esbuild.mjs import path from 'path' import esbuild from 'esbuild' import rails from 'esbuild-rails' import babel from 'esbuild-plugin-babel' esbuild .build({ bundle: true, // Path to application.js folder absWorkingDir: path.join(process.cwd(), 'app/javascript'), // Application.js file, used by Rails to bundle all JS Rails code entryPoints: ['application.js'], // Destination of JS bundle, points to the Rails JS Asset folder outdir: path.join(process.cwd(), 'app/assets/builds'), // Enables watch option. Will regenerate JS bundle if files are changed watch: process.argv.includes('--watch'), // Split option is disabled, only needed when using multiple input files // More information: https://esbuild.github.io/api/#splitting (change it if using multiple inputs) splitting: false, chunkNames: 'chunks/[name]-[hash]', // Remove unused JS methods treeShaking: true, // Adds mapping information so web browser console can map bundle errors to the corresponding // code line and column in the real code // More information: https://esbuild.github.io/api/#sourcemap sourcemap: process.argv.includes('--development'), // Compresses bundle // More information: https://esbuild.github.io/api/#minify minify: process.argv.includes('--production'), // Removes all console lines from bundle // More information: https://esbuild.github.io/api/#drop drop: process.argv.includes('--production') ? ['console'] : [], // Build command log output: https://esbuild.github.io/api/#log-level logLevel: 'info', // Set of ESLint plugins plugins: [ // Plugin to easily import Rails JS files, such as Stimulus controllers and channels // https://github.com/excid3/esbuild-rails rails(), // Configures bundle with Babel. Babel configuration defined in babel.config.js // Babel translates JS code to make it compatible with older JS versions. // https://github.com/nativew/esbuild-plugin-babel babel() ] }) .catch(() => process.exit(1))

Here's the setup I use for reloading with esbuild: https://github.com/excid3/esbuild-rails/blob/main/examples/esbuild.config.mjs

// config/esbuild.mjs import path from 'path' import esbuild from 'esbuild' import rails from 'esbuild-rails' import babel from 'esbuild-plugin-babel' esbuild .build({ bundle: true, // Path to application.js folder absWorkingDir: path.join(process.cwd(), 'app/javascript'), // Application.js file, used by Rails to bundle all JS Rails code entryPoints: ['application.js'], // Destination of JS bundle, points to the Rails JS Asset folder outdir: path.join(process.cwd(), 'app/assets/builds'), // Enables watch option. Will regenerate JS bundle if files are changed watch: process.argv.includes('--watch'), // Split option is disabled, only needed when using multiple input files // More information: https://esbuild.github.io/api/#splitting (change it if using multiple inputs) splitting: false, chunkNames: 'chunks/[name]-[hash]', // Remove unused JS methods treeShaking: true, // Adds mapping information so web browser console can map bundle errors to the corresponding // code line and column in the real code // More information: https://esbuild.github.io/api/#sourcemap sourcemap: process.argv.includes('--development'), // Compresses bundle // More information: https://esbuild.github.io/api/#minify minify: process.argv.includes('--production'), // Removes all console lines from bundle // More information: https://esbuild.github.io/api/#drop drop: process.argv.includes('--production') ? ['console'] : [], // Build command log output: https://esbuild.github.io/api/#log-level logLevel: 'info', // Set of ESLint plugins plugins: [ // Plugin to easily import Rails JS files, such as Stimulus controllers and channels // https://github.com/excid3/esbuild-rails rails(), // Configures bundle with Babel. Babel configuration defined in babel.config.js // Babel translates JS code to make it compatible with older JS versions. // https://github.com/nativew/esbuild-plugin-babel babel() ] }) .catch(() => process.exit(1))

Finally, if you're using esbuild with Rails and Stimulus, you'll probably find the esbuild-rails plugin from Chris Oliver useful.