Library Builds#

The @sigx/vite/lib subpath exports defineLibConfig, a helper that produces a Vite 8 / Rolldown library-build config for @sigx/* packages. It normalizes entries, externalizes the SignalX runtime, and applies sensible defaults so every package builds consistently.

import { defineLibConfig } from '@sigx/vite/lib';

A direct re-export of Vite's own defineConfig is also available from the same subpath, for composing custom configs alongside defineLibConfig:

import { defineLibConfig, defineConfig } from '@sigx/vite/lib';

Single Entry#

The simplest config builds one entry to ES modules:

// vite.config.ts
import { defineLibConfig } from '@sigx/vite/lib';

export default defineLibConfig({
    entry: 'src/index.ts',
});

Output files use the format ${entryName}.js (ES format only). Sourcemaps are on by default, and minification produces additional .min.js files (Oxc-based) unless you set minify: false.

Multiple Entries#

Pass a record (or an array of LibEntry objects) to build multiple entries — useful for packages with subpath exports:

// vite.config.ts
import { defineLibConfig } from '@sigx/vite/lib';

export default defineLibConfig({
    entry: {
        index: 'src/index.ts',
        'server/index': 'src/server/index.ts',
        'client/index': 'src/client/index.ts',
    },
    external: ['sigx', /@sigx\/.*/],
});

The keys become output file names (without extension). The array form is equivalent:

import { defineLibConfig } from '@sigx/vite/lib';

export default defineLibConfig({
    entry: [
        { name: 'index', entry: 'src/index.ts' },
        { name: 'utils', entry: 'src/utils.ts' },
    ],
});

Runtime Externals Are Always Added#

Whatever you pass as external, defineLibConfig always prepends the SignalX runtime tier — sigx, @sigx/reactivity, @sigx/runtime-core, @sigx/runtime-dom, @sigx/server-renderer, and their subpaths — and dedupes the result. This keeps the runtime out of your bundle and preserves singleton reactivity for consumers.

Bundling Sibling Packages with Aliases#

When you need to bundle sibling packages in a monorepo, use alias to map import paths to source files. Pass root: import.meta.url so those relative paths resolve against your package directory:

// vite.config.ts
import { defineLibConfig } from '@sigx/vite/lib';

export default defineLibConfig({
    entry: {
        sigx: 'src/index.ts',
        hydration: 'src/hydration.ts',
    },
    alias: {
        '@sigx/reactivity': '../reactivity/src/index.ts',
        '@sigx/runtime-core': '../runtime-core/src/index.ts',
        '@sigx/runtime-dom': '../runtime-dom/src/index.ts',
    },
    minify: true,
    root: import.meta.url,
});

root accepts a file:// URL (such as import.meta.url) or a directory path. Always set it when you use alias.

JSX Libraries#

Set jsx: true to enable Oxc's automatic JSX transform with import source sigx:

import { defineLibConfig } from '@sigx/vite/lib';

export default defineLibConfig({
    entry: 'src/index.ts',
    jsx: true,
});

Node and CLI Builds#

For a Node-targeted build, set platform: 'node' (targets node18). For a CLI that needs a shebang, use banner:

import { defineLibConfig } from '@sigx/vite/lib';

export default defineLibConfig({
    entry: 'src/cli.ts',
    platform: 'node',
    banner: '#!/usr/bin/env node',
});

Defaults Summary#

Next Steps#

• API Reference — defineLibConfig, LibBuildOptions, and LibEntry
• HMR for Components — component hot-reload in app builds