umi Umi4 SSR doesn't work?

Hi,

Couldn't make SSR working while migrating from Umi3 to Umi4 (4.0.8), if I added the ssr key into config (.umirc.js) this way:

export default {
    svgr: {},

    ssr: {
        serverBuildPath: './dist/umi.server.js'
    }
};

No change if I put it in a basic way:

export default {
    svgr: {},

    ssr: {}
};

umi dev and umi setup throw an error

> [email protected] run
> umi dev

fatal - Error: Parse error @:26:41
    at parse (/Projects/umi/umi-ssr/node_modules/@umijs/bundler-utils/compiled/es-module-lexer/index.js:1:511)
    at parseModuleSync (/Projects/umi/umi-ssr/node_modules/@umijs/bundler-utils/dist/index.js:46:43)
    at parseModule (/Projects/umi/umi-ssr/node_modules/@umijs/bundler-utils/dist/index.js:36:10)
    at async getModuleExports (/Projects/umi/umi-ssr/node_modules/@umijs/preset-umi/dist/features/tmpFiles/getModuleExports.js:29:24)
    at async getRoutes (/Projects/umi/umi-ssr/node_modules/@umijs/preset-umi/dist/features/tmpFiles/routes.js:107:78)
    at async Hook.fn (/Projects/umi/umi-ssr/node_modules/@umijs/preset-umi/dist/features/appData/appData.js:37:19)
    at async /Projects/umi/umi-ssr/node_modules/@umijs/core/dist/service/service.js:114:25 {
  idx: 569
}

my package.json is like this:

{
  "name": "umi-ssr",
  "version": "2.0.0",
  "main": "index.js",
  "license": "MIT",
  "private": true,
  "scripts": {
    "postinstall": "umi setup",
    "run": "umi dev",
    "build": "umi build --clean"
  },
  "dependencies": {
    "ahooks": "^3.6.2",
    "react": "^18.2.0",
    "react-dom": "^18.2.0",
    "umi": "^4.0.8",
    "unirest": "^0.6.0"
  },
  "devDependencies": {
    "@umijs/plugins": "^4.0.8",
    "express": "^4.18.1"
  }
}

Is ssr still a part of UmiJs, or it was removed? Because I don't see it listed on https://umijs.org/docs/api/config either...