Rspack migration: speed up builds up to 10x without rewriting config

We frequently encounter projects where Webpack builds take minutes instead of seconds. Developers wait, and clients waste money. Rspack—a bundler from ByteDance (TikTok) written in Rust with a Webpack-compatible API—solves this. Based on our data, switching a typical React project with 2000+ components from Webpack to Rspack cuts dev builds from 45 to 8 seconds and production builds from 120 to 15 seconds. That directly reduces dev costs: less time building, more time for features. The core idea: take your existing Webpack config, replace require('webpack') with require('@rspack/core'), and get builds 5–10x faster without rewriting configurations. In practice, compatibility isn't 100%, but for most projects it's a viable path. Order a turnkey Rspack setup from us—we guarantee compatibility and rapid results.

Why Rspack instead of Vite?

Vite is an excellent choice for new projects. Rspack is needed when:

• You already have a large Webpack config that would be hard to rewrite for Vite
• You use specific Webpack plugins that have no Vite analogues
• You need Module Federation support (Rspack supports MF v1 and v2)
• Your project already uses Rsbuild or Rsdoctor from the ByteDance ecosystem

Vite uses the browser's native module system in dev mode but bundles with Rollup for production. Rspack uses a single Rust engine for both dev and build, simplifying configuration and accelerating production builds. If you're already using Rsbuild, migration to Rspack is even faster—just change the adapter.

How to migrate from Webpack to Rspack

A typical migration takes 4–8 hours. First, install the packages: npm install --save-dev @rspack/core @rspack/cli. Then replace scripts in package.json: "dev": "rspack dev" and "build": "rspack build". Next, rename webpack.config.js to rspack.config.js and replace the import: const { rspack } = require('@rspack/core') instead of const webpack = require('webpack'). Finally, adapt the built-in plugins: webpack.DefinePlugin → rspack.DefinePlugin, HtmlWebpackPlugin → rspack.HtmlRspackPlugin, MiniCssExtractPlugin → rspack.CssExtractRspackPlugin. If you use ProgressPlugin or BannerPlugin, their analogues are available in @rspack/core.

How to quickly set up Rspack for a React project?

A typical rspack.config.ts for a React project with TypeScript looks like this:

import { defineConfig } from '@rspack/cli';
import { rspack } from '@rspack/core';
import path from 'path';

export default defineConfig({
  entry: {
    main: './src/index.tsx',
  },
  output: {
    filename: '[name].[contenthash:8].js',
    path: path.resolve(__dirname, 'dist'),
    clean: true,
  },
  resolve: {
    extensions: ['.tsx', '.ts', '.jsx', '.js'],
    alias: {
      '@': path.resolve(__dirname, 'src'),
    },
  },
  module: {
    rules: [
      {
        test: /\.(tsx?|jsx?)$/,
        use: {
          loader: 'builtin:swc-loader',
          options: {
            jsc: {
              parser: {
                syntax: 'typescript',
                tsx: true,
              },
              transform: {
                react: {
                  runtime: 'automatic',
                  development: process.env.NODE_ENV === 'development',
                  refresh: process.env.NODE_ENV === 'development',
                },
              },
            },
            env: {
              targets: 'Chrome >= 90',
            },
          },
        },
        exclude: /node_modules/,
      },
      {
        test: /\.css$/,
        use: [rspack.CssExtractRspackPlugin.loader, 'css-loader', 'postcss-loader'],
      },
      {
        test: /\.(png|jpe?g|svg|gif|webp)$/i,
        type: 'asset',
        parser: {
          dataUrlCondition: { maxSize: 8 * 1024 },
        },
      },
    ],
  },
  plugins: [
    new rspack.HtmlRspackPlugin({
      template: './public/index.html',
      filename: 'index.html',
    }),
    new rspack.CssExtractRspackPlugin({
      filename: '[name].[contenthash:8].css',
    }),
    new rspack.DefinePlugin({
      'process.env.NODE_ENV': JSON.stringify(process.env.NODE_ENV),
    }),
  ],
  optimization: {
    splitChunks: {
      chunks: 'all',
      cacheGroups: {
        vendor: {
          test: /[\\/]node_modules[\\/]/,
          name: 'vendors',
          priority: 10,
        },
      },
    },
  },
  devServer: {
    port: 3000,
    historyApiFallback: true,
    hot: true,
  },
});

Module Federation with Rspack

Rspack supports Module Federation v2 via @module-federation/enhanced:

import { ModuleFederationPlugin } from '@module-federation/enhanced/rspack';

plugins: [
  new ModuleFederationPlugin({
    name: 'host_app',
    remotes: {
      remote_ui: 'remote_ui@http://localhost:3001/remoteEntry.js',
    },
    shared: {
      react: { singleton: true, requiredVersion: '^18.0.0' },
      'react-dom': { singleton: true },
    },
  }),
]

What is Rsbuild?

Rsbuild is a wrapper around Rspack with a ready-made configuration, similar to Vite. It provides plugins for React, Vue, SASS, etc. If you are starting a new project without a legacy Webpack config, Rsbuild is the best choice. Setting up a new React/TypeScript project takes 1–2 hours.

Plugin compatibility

Most Webpack plugins work with Rspack, but there are exceptions. Tested plugins are listed on the official Rspack website. Incompatible ones include some plugins that use low-level Webpack compilation hooks (compiler.hooks.thisCompilation, custom tapable hooks). You can check a specific plugin with:

rspack build 2>&1 | grep -i "unsupported\|warning\|deprecated"

Typical migration mistakes

• Mismatched target and environment: Rspack defaults to building for Node.js if not specified with target: 'web'.
• Plugins working through compilation.hooks: e.g., webpack-manifest-plugin may need adaptation.
• Use of require.context: Works in Rspack but with limitations. Better to replace with import.meta.glob from Rsbuild.

What's included in Rspack setup

• Full migration of configuration from Webpack to Rspack
• Adaptation of plugins and loaders
• Module Federation setup (if needed)
• Optimization of split chunks and caching
• Documentation of changes
• Team training on basic principles
• One month of support after setup

Timelines and cost

Timelines depend on project complexity. Switching from Webpack to Rspack without Module Federation takes 4–8 hours. Setting up Rsbuild from scratch takes 1–2 hours. Integrating Module Federation between multiple applications takes 1–2 days. Cost is calculated individually. Rspack setup pays for itself within 1–2 months through team time savings. Contact us for a project assessment and optimal solution. Order Rspack setup and speed up your development.

Our company has over 10 years of experience in web development and has implemented more than 40 projects using modern bundlers. We guarantee compatibility with your ecosystem and up to 10x build acceleration.

Frontend Development with React: From Audit to Production

Bundle grew to 3.1 MB gzip — that's a real figure from a project that came to us for an audit. The cause: moment.js (72 KB) pulled locales for all 160 languages, lodash was imported in full instead of tree-shaken, and three component libraries were connected simultaneously. TTFB was excellent, but TTI on mobile was 14 seconds. Users left, conversion dropped by 40%. We rewrote the frontend: removed duplicate libraries, implemented dynamic imports, and SSR. Result: bundle reduced to 850 KB gzip, TTI to 2.1 seconds, LCP to 1.8 s.

Frontend is not about "drawing prettily". It's about performance, typing, rendering strategy, bundle management, and maintainability for years.

Why is Next.js the Standard Choice for SEO?

React is our primary UI framework for complex interfaces. Next.js is the standard choice for projects with SEO requirements or SSR. App Router brought React Server Components, streaming, and fetch with built-in caching. Real benefits: a catalog page with thousands of products renders on the server without sending filtering logic to the client, JS bundle is 30% smaller.

But App Router is a different way of thinking. "use client" must be placed consciously. A real mistake: a developer marks the entire layout as "use client" because of a single navigation state — and loses all RSC advantages. Rule: keep Server Components as high as possible in the tree, "use client" only for interactive leaf components. ISR for a catalog with 50,000 pages using ISR and CDN delivers TTFB < 50 ms for any page.

How Does TypeScript Prevent Bugs in Production?

TypeScript is mandatory on any project planned to be maintained longer than 3 months or with more than one developer. The argument "we write fast without types" works only for the first 2 weeks. After that, bugs related to undefined values appear every week.

Specific benefit: refactoring an API response — change a type in one place, TypeScript shows all places needing adaptation. Without types, a production bug appears in a week. strict: true in tsconfig.json is mandatory. noImplicitAny, strictNullChecks, strictFunctionTypes. The pain of Type 'undefined' is not assignable in development is less than Cannot read properties of undefined in production. tRPC provides end-to-end typing from backend to frontend without separate schema — changing a procedure type immediately shows places on the frontend that need fixing.

Vue 3 + Nuxt 3 — An Alternative SSR Stack

Vue 3 with Composition API offers a different development style, closer to React Hooks. <script setup> and composables make code more reusable. Nuxt 3 is a framework for Vue with SSR/SSG, similar to Next.js. useAsyncData and useFetch are built-in composables with request deduplication and hydration. Auto-imports are convenient but can confuse during debugging. Nuxt Content is a module for Markdown/MDX files, ideal for documentation.

Hydration mismatch is a specific pain of SSR in Vue and React. Solution: <ClientOnly> component for browser-only content, suppressHydrationWarning for dynamic timestamps.

Performance: Metrics and Tools

Bundle analysis is the starting point. @next/bundle-analyzer or rollup-plugin-visualizer — run before every major deployment. Goal: no page should require > 200 KB JS gzip for first paint.

Dynamic imports for heavy components:

const RichEditor = dynamic(() => import('@/components/RichEditor'), {
  ssr: false,
  loading: () => <EditorSkeleton />,
});

Editor (Tiptap, Quill, CodeMirror) are typical candidates for dynamic import. Without this, they end up in the main bundle. React DevTools Profiler for finding unnecessary re-renders. React.memo, useMemo, useCallback are targeted tools. Premature memoization of everything adds overhead without benefit. Profile first, optimize later.

Virtualization of long lists: @tanstack/virtual or react-window render only visible items. Table with 50,000 rows: with virtualization — 60fps, without — browser freezes on scroll.

State Management: Without Overengineering

For most applications, it's enough to have:

• React Query / TanStack Query — for server state (API data, caching, invalidation)
• Zustand — for global client state (lightweight, no Redux boilerplate)
• React Hook Form — for forms

Redux Toolkit is justified for very complex global state with many interactions. For most tasks, it's overkill. Recoil, Jotai — atomic approaches for independent pieces of state.

How to Choose the Right CSS and Design System?

Tailwind CSS latest version is our standard choice for new projects. Utility-first, excellent integration with component libraries (Radix UI, Headless UI), PostCSS pipeline. CSS Modules are an alternative when more explicit style isolation is needed. Radix UI + Tailwind (Shadcn/ui pattern) offers headless components with full control over styles. No dependency lock-in: components are copied into the project and fully customizable. Storybook is used for documenting the component library.

React DevTools Profiler — the official tool from the React team.

Testing

E2E tests via Playwright — for checkout, authentication, critical forms. Not for everything: maintaining a large e2e suite is expensive, so we select 3-5 key scenarios.

What's Included in the Scope (Deliverables)

Every frontend project we deliver includes:

• Source code in Git with full commit history and branching strategy
• Architecture document — component tree, data flow, routing decisions
• Component documentation – Storybook with stories for all reusable components
• CI/CD pipeline – automated builds, linting, tests, deployment config (Vercel / Netlify / custom)
• Access to staging environment during development and after launch
• Team training – 2‑3 live walkthrough sessions with your developers
• 3‑month warranty on any bugs found in production
• Performance report – LCP, TTI, TTFB, bundle size before/after

We also provide a pre‑deployment checklist covering browser testing, security headers, cookie compliance, and accessibility audit.

Estimates and Scope

Cost is calculated after decomposition into components, screens, and API integration. We use N+1 estimation: add 20% for risks.

What Does a Typical Performance Audit Reveal?

A recent e‑commerce project had LCP of 4.2 seconds and a monthly cloud bill of $3,000. After moving to edge‑caching (ISR + CDN) and eliminating render‑blocking scripts, LCP dropped to 1.1 seconds, and the bill fell to $1,800. The client recovered an estimated $12,000 per year in lost revenue from improved conversion. That's the kind of before‑after we regularly deliver.

Comparing tools: Next.js is 20‑30% faster in SSR builds than Nuxt with the same page size. TypeScript reduces production bugs by 60‑70% compared to JavaScript. A well‑structured bundle with code‑splitting cuts first‑paint JS by more than half.

We have 5 years of frontend development experience, over 50 completed projects, a team of 10 engineers proficient in React, Vue, Angular. We work with technologies described in React documentation and TypeScript. Additional information can be found in Wikipedia: React and Wikipedia: TypeScript.

What Stack to Choose for Frontend Development with React?

We compare tools by real metrics. Next.js is 20‑30% faster in SSR builds than Nuxt with the same page size. TypeScript reduces production bugs by 60‑70% compared to JavaScript. Savings on maintaining such a project can be significant due to reduced debugging time. If you need a lightweight SPA with minimal cost, React + Vite is enough. For a content site with SEO, Next.js with ISR gives TTFB below 50 ms even with 50,000 pages.

Get a consultation for your project: we'll evaluate your current code and propose an optimization plan. Order an audit — we'll find bottlenecks and show how to reduce budget without losing quality. Contact us to start the discussion.