Create a plugin

Ness 7 plugins use the standard Vite plugin contract. Public official plugins use the @nessframework/* scope; community plugins can use any npm package name.

Vite plugin

ness-example/src/index.js

export default function example(options = {}) {
  return {
    name: 'ness:example',
    config() {
      return {
        resolve: {
          alias: { '@example': options.directory || '/src/example' },
        },
      };
    },
  };
}

Enable it inside the Ness Vite integration:

ness.config.mjs

import { defineNessConfig } from '@nessframework/router';
import { ness } from '@nessframework/router/vite';
import example from 'ness-example';

export default defineNessConfig({
  vite: { plugins: [ness({ plugins: [example()] })] },
});

Plugins can use any Vite hook, including config, transform, generateBundle, configureServer, and handleHotUpdate.

ness() flattens the plugins array and drops falsy entries, so a factory may return several Vite plugins at once and an entry can be gated with condition && plugin(). The entries are registered after the framework's own plugins and React Router's, and before the development error overlay.

Package exports

ness-example/package.json

{
  "name": "ness-example",
  "type": "module",
  "exports": {
    ".": "./src/index.js"
  }
}

Migrating a Ness 5 plugin

Ness 5 and 6 plugins exported an install(config, options) function that mutated a Webpack configuration. That runtime was removed in Ness 7, and install is no longer called.

Rewrite the plugin as a Vite plugin. Most of the mapping is direct:

Ness 5 (install)	Vite plugin
config.resolve.alias	return { resolve: { alias } } from config()
config.module.rules	transform(code, id)
config.plugins.push(...)	a Rollup hook such as generateBundle
config.devServer.headers	return { server: { headers } } from config()
options.dev / options.env	the environment.command argument to config()