Bitrix24 Application Development with React: Widgets and SPAs

We develop external web applications in React that are embedded into the Bitrix24 interface via an iframe or opened in a separate tab. Bitrix24 application development with React is our specialty. Over 5 years we have created more than 30 projects: from simple widgets to full-fledged standalone SPAs. A typical problem: standard Bitrix24 lacks SLA control in CRM. Our React application solves this with a widget in the deal card. Applications work through the Bitrix24 REST API, receive user context via the BX24.js SDK, and are placed in various locations: CRM sidebar, lead card, portal header, separate application page. React is the natural choice for such applications: component-based approach, rich ecosystem, TypeScript typing for REST API. We guarantee stable operation on all Bitrix24 versions (cloud and on-premise) and certify solutions according to security standards.

What problems do React applications in Bitrix24 solve?

Standard Bitrix24 does not cover all business scenarios: there is no SLA control in CRM, no flexible interfaces for external ERP, limited real-time notification capabilities. React applications fill these gaps by integrating into the portal interface. Typical pain points:

• Lack of SLA visualization: managers cannot see how long a deal has been stuck at a stage. Our widget with a timeline and color indication solves this.
• Complex integrations: external ERPs require custom UI that cannot be implemented with standard components. A React application with its own backend proxies data and displays it inside Bitrix24.
• Limited reports: built-in reports do not allow building complex dashboards. React + D3.js provides any charts.

Architecture of Bitrix24 applications on React

The application is divided into three layers: React frontend (SPA), custom backend (Laravel / Node.js), and the Bitrix24 REST API. The frontend communicates with the backend, and the backend communicates with Bitrix24 via server tokens or webhooks. This hides keys from the browser and allows caching data.

OAuth authentication workflow

Authorization uses OAuth 2.0. Bitrix24 issues an access_token when the application opens in an iframe (via postMessage or URL parameters). For server requests, authorization via client_id + client_secret + webhook. Typical architecture: React frontend makes requests to its own backend (not directly to Bitrix24), and the backend proxies to the Bitrix24 REST API with the server token. This hides tokens from the browser and allows caching repeated requests. According to the Bitrix24 REST API documentation, it is recommended to use Authorization Code Flow with PKCE for enhanced security.

// React hook for calling Bitrix24 REST via BX24.js (client side)
function useBX24Method<T>(method: string, params: object) {
  return useQuery({
    queryKey: ['bx24', method, params],
    queryFn: () =>
      new Promise<T>((resolve, reject) => {
        window.BX24.callMethod(method, params, (result: any) => {
          if (result.error()) reject(result.error());
          else resolve(result.data());
        });
      }),
    staleTime: 30_000,
  });
}

// Usage
const { data: deals } = useBX24Method<Deal[]>('crm.deal.list', {
  select: ['ID', 'TITLE', 'STAGE_ID', 'OPPORTUNITY'],
  filter: { ASSIGNED_BY_ID: currentUserId },
  order:  { DATE_MODIFY: 'DESC' },
});

Using the Bitrix24 UI Kit in a React application

Bitrix24 provides the official package @bitrix24/b24jssdk with a set of React components: Button, Input, Select, Table, Modal. They are styled via CSS variables and automatically adapt to the portal theme (light/dark). Using the UI Kit ensures that the application looks like a native part of Bitrix24 — users do not notice the transition.

import { Button, Modal } from '@bitrix24/b24jssdk';

function MyApp() {
  return (
    <>
      <Button>Open</Button>
      <Modal show={true}>
        <p>Modal content</p>
      </Modal>
    </>
  );
}

Case study: application for SLA control in CRM

From practice: a B2B services company, 45 managers, deals go through 8 stages. Task: a widget in the deal card showing how long the deal has been on the current stage, a flag for SLA violation (if longer than the norm), and a history of stage transitions. Out-of-the-box Bitrix24 does not have SLA control in CRM Deal.

Implementation: Backend — Laravel (separate server). On each deal stage change, a webhook from Bitrix24 (event: ONCRMDEALUPDATE) writes the transition to a deal_stage_history table with timestamps. The React widget is embedded in CRM_DEAL_DETAIL_TAB. When the card is opened, a request to our backend with DEAL_ID returns: current stage, time on stage, SLA norm for that stage, status (normal / violated), and a list of transitions. Visualization: a stage timeline with color indication. Red — SLA violated, yellow — 75% of time used, green — normal.

function SlaWidget({ dealId }: { dealId: number }) {
  const { data } = useSlaData(dealId);

  if (!data) return <Spinner />;

  return (
    <div className="sla-widget">
      <SlaTimer
        currentStage={data.currentStage}
        timeOnStage={data.timeOnStage}
        slaLimit={data.slaLimit}
        status={data.status}
      />
      <StageTimeline history={data.stageHistory} />
    </div>
  );
}

Notifications: when an SLA is violated, the backend sends a notification to the responsible manager and their supervisor via im.notify.system.add REST API.

React widgets load 3 times faster than classic PHP includes due to caching and asynchronous requests on the custom backend. Reduction in SLA monitoring costs — up to 70%. The savings amounted to about 15,000 RUB/month.

Integration via webhooks

Bitrix24 applications can subscribe to events via webhooks: changes to deals, tasks, contacts. This allows building near-real-time updates. For real-time in React — Server-Sent Events (SSE) or polling. WebSocket over Bitrix24 — only via BX24.callMethod('pull.application.event.add') with the Push & Pull module.

Process and timelines

1. Analysis — determine embedding locations, API methods, authorization scheme.
2. Design — application architecture, prototype design.
3. Register the application in Bitrix24, configure OAuth, obtain client_id/client_secret.
4. Backend development — REST proxy, business logic, webhooks.
5. React SPA development — components, state, integration with BX24.js.
6. Testing on a real portal, edge cases of authorization.
7. Deployment — HTTPS, iframe configuration, Marketplace verification.
8. API and deployment documentation.
9. Training portal administrators.
10. Post-launch support (on request).

Timelines: simple embedded widget — 1–2 weeks. Full standalone application with its own backend — 4–12 weeks depending on functionality. We will evaluate your project — contact us to discuss. Get a consultation: our experience guarantees quality and adherence to deadlines. Order application development to discuss your task and get a preliminary estimate.

What Does React Development for 1C-Bitrix Provide and When Is It Needed?

A catalog with 30,000 SKUs and a faceted filter — the standard Bitrix template loads the page in 3 seconds. A B2B cabinet with personalized discounts — price recalculation with every filter change. The bottleneck is not the data but the monolithic architecture: each block calls REST separately, 6–8 sequential requests of 200–500 ms result in a total delay of 2–3 seconds. React solves this radically: component model, virtual DOM, and library ecosystem turn a slow interface into a responsive application. We are a certified 1C-Bitrix partner with 10+ years of experience and over 500 completed projects. Order an audit — we will evaluate your project in 1–2 days and show cases similar to yours.

Architectural Approaches

SPA on React + REST API Bitrix (BX.rest)

The React application lives separately, accessing /rest/ or custom endpoints via CRestServer. Maximum control, but also maximum work.

• Client-side routing with React Router — transitions without reload, but on F5 you need a catch-all on Nginx: try_files $uri /index.html
• Optimistic updates: cart updates instantly, sale.basket.update flies in the background. On error, roll back state and show a toast
• Frontend deploys to CDN independent of Bitrix — updated a button without touching the backend

SSR with Hydration — When Yandex Doesn't See SPA

Yandex has learned to render JS, but not perfectly; Googlebot is better, but still not 100%. Server-side rendering of React components via Node.js solves the problem radically: the bot receives ready HTML, the user gets an interactive application after hydration. FCP drops below one second on normal hosting, og:title and og:image work for social networks. The complexity is needing a Node.js process alongside Apache/Nginx serving Bitrix: two runtimes, two deploys, two log sets. Bitrix cache (CPHPCache, Composite) can be used to warm data that later goes to SSR.

Headless Bitrix — Admin Panel for Content Managers, React for Visitors

Content manager logs into /bitrix/admin/, edits infoblocks. The visitor sees a React application that retrieves data via API. One backend serves the site, mobile app, and Telegram bot. Scaling: React bundle on CloudFront/CDN, Bitrix on a single server. With 50,000 unique visitors, the frontend does not directly load the backend. Pitfall: the standard Bitrix visual editor (BXEditor) stops working for visitors — content managers will have to work only through the admin panel.

Stack and Component Architecture

Stack We Actually Use

How We Build Components and Type Data

Every project starts with a design system — otherwise, by the third month, three developers will write three different button components. Typography, colors, spacing — via CSS variables and Tailwind config. Forms: inputs with masks (phone, INN), searchable selects, file upload with preview and MIME validation. Product card is a separate story: price with discounts from CCatalogProduct::GetOptimalPrice(), labels "Hit"/"New" from infoblock properties, "Add to cart" button with loading/success/error states. Tables with virtualization (react-window) for price lists of 5000+ rows.

We type everything that comes from Bitrix. The REST API returns string where you'd expect number, "Y"/"N" instead of boolean, and null instead of empty array. A Zod schema on input parses and transforms — components get proper types.

// Real type of CIBlockElement via REST — surprises everywhere
interface BitrixProduct {
  ID: string;          // yes, string, not number
  ACTIVE: "Y" | "N";  // not boolean
  PRICE: string;       // also string
  QUANTITY: string;    // and this is string
}

Performance and API Integration

Aggregating endpoints are key. One ajax.php or custom controller on \Bitrix\Main\Engine\Controller gathers catalog data, filters, cart, and user in a single request. React Query caches the response, and a second visit returns from cache with staleTime — load time reduces by 60% already on the second load.

How Does React Improve Core Web Vitals?

• LCP < 2.5 s — lazy loading images via loading="lazy", inline critical CSS, preload LCP image via <link rel="preload">
• INP (replaces FID) < 200 ms — useTransition for heavy filtering, useDeferredValue for search input
• CLS < 0.1 — fixed sizes for skeletons and images. Skeleton placeholders instead of spinners

Virtualization is not optional, but necessary. A catalog with faceted filter may return 500 products per page. React-window or react-virtuoso render only the visible 20–30 cards — DOM does not bloat, scrolling is smooth.

REST and Custom Controllers

Out of the box via /rest/: infoblocks (iblock.element.get), cart (sale.basket.*), orders (sale.order.*), users (user.*). For a simple catalog, that's enough. But 70% of tasks require custom endpoints. \Bitrix\Main\Engine\Controller is the standard way to create your own endpoints in D7. Write a controller, register via registerAction, get endpoint with CSRF protection and authorization out of the box.

• Aggregation: one request = catalog data + filters + cart + user
• WebSocket via Bitrix Push & Pull (CPullStack::AddByTag) — order status updates in real time, no polling
• GraphQL middleware (webonyx/graphql-php) on top of D7 ORM — frontend requests exactly the fields it needs. Mobile traffic savings up to 40%

Projects, Timelines, and What's Included

Typical Projects We Have Already Done

• Online store with 30,000 SKUs and faceted filter via \Bitrix\Iblock\PropertyIndex\Facet — SPA, React Query, catalog virtualization
• B2B cabinet: personalized prices from CCatalogGroup, reconciliation statements from 1C via \Bitrix\Sale\Compatible\OrderCompatibility, order history with filtering
• Corporate portal: dashboards on Recharts, real-time via Push & Pull, integration with internal APIs through middleware
• Marketplace: two React applications (buyer + seller), common backend, data separation via CUser::GetUserGroup()

Timelines and What's Included

• Audit of current Bitrix code and architecture
• Design of API layer (REST / custom controllers / GraphQL)
• Development of design system and components
• CI/CD setup (deploy React bundle independently of Bitrix)
• Documentation of endpoints and types (Swagger / TypeScript types)
• Transfer of access to server, admin panel, repository
• Training content managers to work through the admin panel
• Warranty support for 2 months after delivery

Exact numbers after scope analysis. Assessment is phased, with a fixed budget for each sprint.

How We Implement React in a Project

1. Audit existing code — find bottlenecks: redundant requests, outdated templates, suboptimal caches.
2. Design API layer — determine which endpoints are needed, design aggregators or GraphQL.
3. Develop design system — create components (buttons, forms, cards) based on mockups or UX recommendations.
4. Integrate with Bitrix via chosen approach (SPA, SSR, or Headless) — set up rendering and routing.
5. Test and deploy — launch a pilot section (e.g., catalog), measure Core Web Vitals, upon approval expand.

Why React, Not Vue or Bitrix Templates

• Ecosystem. For any UI task, there is a ready library: tables, charts, drag-and-drop, virtualization. For Vue, the choice is narrower; for Bitrix templates, almost absent.
• Talent pool. Finding a React developer is three times easier than a Bitrix templater who knows D7 and template.php.
• React Native. Components are reused in mobile app — not one-to-one, but business logic and types are shared.
• Gradual adoption. Start with one section (/catalog/) on React, keep the rest on Bitrix templates. component_epilog.php loads the React bundle, data is passed via window.__INITIAL_DATA__.

1C-Bitrix + React is not a theoretical architecture but a working combination that already serves catalogs with tens of thousands of SKUs and B2B cabinets with heavy business logic. Learn more about React and 1C-Bitrix. Get a consultation — we will send you cases similar to your project. Contact us to discuss details. We implement turnkey with a guarantee of results.