You're building a multi-page React site with dozens of pages. Each shares common components, routing, and utilities. Webpack builds: 15 seconds incremental, 2 minutes full. The config has ballooned to 200 lines. One library update triggers a rebuild of all chunks. This slows development and inflates traffic.
We integrate Import Maps – a native browser mechanism for managing ES modules without a bundler. Instead of bundling, the browser resolves dependencies from a map. Results: zero build time, separate caching, simple updates. In our experience, this saves up to 40% on traffic and cuts LCP by 20–30% compared to Webpack.
Problems We Solve
Slow Build Times
Even with Webpack 5, incremental builds are an illusion. Change one file, and the tool rebuilds dependent chunks. With Import Maps, no build is needed: write code, place the file on the server, refresh the page. The server just serves static files. Compilation time drops to zero – development becomes edit-and-refresh without waiting.
Version Conflicts
Classic sites with jQuery and multiple plugins often suffer version conflicts where different parts expect different library versions. Import Maps solves this with scopes: for /admin/ paths, you can specify one React version, for the main site another. No globals, no hacks. Version resolution happens at the browser level, not in the build.
How We Implement Import Maps
Our process starts with a thorough audit of your stack. We identify shared dependencies, analyze version requirements, and choose the best CDN (esm.sh, jsDelivr, or self-hosted). Then we design the import map with scopes and caching strategy, implement it in your templates, adapt modules to ES imports, and test performance with Core Web Vitals.
A Concrete Case
On a project with a 5-page React SPA and three admin interfaces, we replaced a Webpack 5 build with Import Maps using esm.sh. Initial bundle size dropped from 1.2 MB to 400 KB (only what's used per page). Incremental builds became instant – developers saved an average of 2 minutes per hot reload. LCP improved by 25% across all pages.
Process for Estimating and Delivering
-
Audit: Review current stack, list shared dependencies, assess versions, choose CDN.
-
Design: Build import map, define scopes, plan caching strategy, fallback for legacy browsers.
-
Implement: Add import map to templates, refactor modules to ES imports, configure server MIME types.
-
Test: Verify module loading, performance (Lighthouse), no regressions.
-
Deploy: Push to production, monitor errors, set CDN caching headers.
We don't offer fixed prices because every project is different. After a free audit, we provide a tailored estimate.
Timeline Benchmarks
Typical projects range from 1 to 3 weeks, depending on site complexity and number of pages. A simple 5‑page site with a few shared dependencies can be done in a week. Larger projects with dozens of pages and custom scopes may take up to three weeks.
Common Mistakes to Avoid
-
Forgetting to preload the import map: The
<script type="importmap"> must load before any module script.
-
Using bare specifiers without scoping: If different sections need different versions, always use scopes.
-
Ignoring MIME types: Your server must serve
.mjs files with application/javascript or text/javascript.
-
Not testing on all browsers: Even though modern browsers support Import Maps, verify with Safari and Firefox.
Comparison: Webpack vs Import Maps for MPA
| Metric |
Webpack (typical MPA) |
Import Maps |
| Build time |
>10 seconds per rebuild |
0 seconds (no build) |
| Vendor caching |
Config‑dependent, often duplicated |
Native separate caching |
| Initial traffic |
Full bundle (often >1 MB) |
Only used modules |
| Typical LCP |
Varies with bundle size |
20–30% reduction |
Choosing a CDN
| Provider |
Version pinning |
Speed |
Full control |
| esm.sh |
Yes |
High |
No (but stable) |
| jsDelivr |
Yes |
High |
No |
| Self-hosted |
Yes |
Server-dependent |
Yes |
For most projects, we recommend esm.sh – it supports version pinning and auto-optimizes modules.
Example of using scopes
{
"imports": {
"react": "https://esm.sh/[email protected]"
},
"scopes": {
"/admin/": {
"react": "https://esm.sh/[email protected]"
}
}
}
Setting up Import Maps for a Multi-Page Site
- Identify shared dependencies (React, utilities).
- Choose a host (CDN or self-hosted).
- Create the import map in your HTML template – load it before any module script.
- For local modules, use a prefix like
@/ or map them directly.
- Verify network loading in browser DevTools.
Example base map:
<script type="importmap">
{
"imports": {
"react": "https://esm.sh/stable/[email protected]/es2022/react.mjs",
"react-dom/client": "https://esm.sh/stable/[email protected]/es2022/client.mjs",
"htm/react": "https://esm.sh/[email protected]/react",
"@/": "/static/js/"
}
}
</script>
What Our Work Includes
- Full stack audit and dependency mapping.
- Import map design with scopes and caching strategy.
- Implementation: integrating the map into templates, refactoring modules to ES imports.
- Testing of loading, performance (Core Web Vitals), and no regressions.
- Documentation and team training on native module workflow.
Why Work With Us
Our team has over 10 years of production experience with web stacks (Bitrix, 1C, React) and has completed 40+ projects involving native module migration. We guarantee correct caching and support for all modern browsers.
Ready to eliminate build times? Contact us for a free audit of your current stack. We'll evaluate where Import Maps can make an impact and propose a custom solution.
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
| Level |
Tool |
What We Test |
| Unit |
Vitest |
Utilities, hooks, pure functions |
| Component |
Testing Library |
Render, interactions |
| E2E |
Playwright |
Critical user flows |
| Visual |
Chromatic (Storybook) |
UI regression |
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
| Task |
Timeline |
| SPA (dashboard, CRM interface) |
8–16 weeks |
| Next.js site with SSR/ISR |
6–14 weeks |
| Frontend for existing API |
4–10 weeks |
| Component library (design system) |
6–12 weeks |
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.
