@ir-kit/fn-schema-unplugin

Bundler plugin for fn-schema. Resolves a virtual module to the extracted bundle, with HMR on source change in Vite. Built on unplugin — same package powers Vite, webpack, Rollup, esbuild, Rspack, Rolldown, and Farm.

When to use it

You have a Vite/Next/webpack app and want fn-schema results available via a regular import — without running the cli as a separate process. The plugin keeps a warm Project instance during dev and triggers a reload when source files change.

Install

pnpm add -D @ir-kit/fn-schema-unplugin

Vite

// vite.config.ts
import { defineConfig } from "vite"
import fnSchema from "@ir-kit/fn-schema-unplugin/vite"

export default defineConfig({
  plugins: [
    fnSchema({
      files: "src/api/**/*.ts",
      schema: { identity: "x-fn-schema-ts", transport: "x-fn-schema-transport" },
    }),
  ],
})

// app code
import schemas from "virtual:fn-schema/bundle"
import { createReader } from "@ir-kit/fn-schema-loader"

const reader = createReader(schemas)

Other bundlers

// webpack
const fnSchema = require("@ir-kit/fn-schema-unplugin/webpack").default

// rollup
import fnSchema from "@ir-kit/fn-schema-unplugin/rollup"

// esbuild
import fnSchema from "@ir-kit/fn-schema-unplugin/esbuild"

Subpath exports also exist for /rspack, /rolldown, /farm.

Options

interface FnSchemaPluginOptions {
  files: string | string[]            // required
  cwd?: string                         // default: process.cwd()
  tsConfigPath?: string
  virtualModuleId?: string             // default: "virtual:fn-schema/bundle"
  // …all extract options (include, exclude, signature, schema, naming, hooks)
}

CLI vs unplugin

| | CLI | unplugin | |---|---|---| | extra dev process | yes | no | | HMR on schema change | manual (your watcher) | built-in (Vite) | | works outside a bundler | yes | no | | produces disk artifact (schemas.json) | yes | no (in-memory) |

Use the CLI when you want a checked-in schemas.json — for backend Node servers, deployment validation, or sharing across services. Use unplugin when fn-schema is a per-app dev concern.