Adapter Configuration

Every field on EsBuildAdapterConfig — plugins, fileReplacements, loader — and the two fields that are declared but inert in v3.

createEsBuildAdapter takes one object:

interface EsBuildAdapterConfig {
  plugins: esbuild.Plugin[];
  fileReplacements?: Record<string, string | { file: string }>;
  loader?: { [ext: string]: esbuild.Loader };
  skipRollup?: boolean;
  compensateExports?: RegExp[];
}

plugins is the only required field. esBuildAdapter, the ready-made export, is exactly createEsBuildAdapter({ plugins: [] }).

plugins

Standard esbuild plugins, passed straight to the esbuild pass:

import { createEsBuildAdapter } from '@softarc/native-federation-esbuild';
import svelte from 'esbuild-svelte';

const adapter = createEsBuildAdapter({
  plugins: [svelte()],
});

They apply to every entry point the core hands over — exposed modules, shared mappings and shared packages alike. They do not apply to the rollup pre-pass that packages go through first, so a plugin that has to see a package's original CommonJS source will not fire.

fileReplacements

Rewrites an entry point's path before the rollup pre-pass runs. The key is matched against the end of the path; the value is what replaces it:

createEsBuildAdapter({
  plugins: [],
  fileReplacements: {
    'node_modules/react/index.js': 'node_modules/react/cjs/react.production.min.js',
  },
});

Both the shorthand above and the long form { file: '...' } are accepted. This only affects packages — workspace files never take the rollup path, so replacing one has no effect.

The main use is pointing a package at a build variant that converts cleanly. reactReplacements ships ready-made maps for dev and prod; see React & CJS Interop.

loader

Passed through to esbuild's loader option, mapping a file extension to how it should be handled:

createEsBuildAdapter({
  plugins: [],
  loader: {
    '.svg': 'text',
    '.png': 'dataurl',
  },
});

Declared but inert

Two fields exist on the type in 3.5.5 but do nothing:

They are safe to pass — they are simply ignored. Do not rely on them to change behaviour.

What the adapter fixes for you

Everything else is derived from the options the core passes:

There is no hook for overriding those; if you need different behaviour, write your own adapter against the BuildAdapter contract — it is one function.

Related

• Getting Started — where the adapter is plugged in.
• React & CJS Interop — the rollup pre-pass in practice.