Website Personalisation

Overview

Reelevant offers three complementary approaches for website personalisation. Choose one or combine them depending on your requirements:

Reelevant Client Side Script

A JavaScript tracking script that loads in the browser, fetches personalised content, and injects it into your page. Ideal for event tracking, consent-dependent content, overlays, and no-code integrations via the browser extension.

Reelevant Server Side SDK

A Node.js / Edge SDK that fetches personalised content during server render. Content arrives in the initial HTML — zero layout shift, full SEO visibility, instant display.

Reelevant as API (JSON)

A headless personalisation API that returns structured JSON. You control the rendering — use your own components, design system, or native mobile UI with personalised data from Reelevant.

When to use which

	Client-Side Script	Server-Side SDK	API (JSON)
How it works	JavaScript loads after page render, fetches content, injects into DOM	Content fetched during server render, included in HTML response	Your app calls the runner and receives structured JSON data
Layout shift (CLS)	Content appears after load — visible shift	Zero — content is in the initial HTML	You control rendering — no CLS if data is fetched server-side
SEO	Not indexed (injected after page load)	Fully indexed by search engines	Depends on your rendering strategy
Time to content	Depends on client network + runner latency	Included in first paint	Depends on when you call the API
Best for	Event tracking, consent, dynamic overlays, SPAs, no-code setup	Hero banners, product recommendations, landing pages, SEO-critical zones	Custom UI components, mobile apps, headless architectures, design systems
Setup effort	Paste a script tag or use the browser extension	Install an npm package and add server-side code	Create a JSON Template, call a single endpoint

All three approaches work together. Server-rendered zones are marked with data-rlvt-ssr="true" — the client script automatically skips them. JSON API calls can be made from either client or server depending on your architecture.

Content types

The Reelevant runner can return three content formats. Your workflow’s output node determines which format is used:

Type	Description	Use case
HTML	Responsive HTML partial	Banners, product cards, rich content blocks
JSON	Structured data object	Headless personalisation — build your own UI with personalised data
Image	Binary image (PNG, etc.)	Static visual banners, email-style images on web

Identity management

All three approaches share the same identity cookies:

Cookie	Purpose
`rlvt_clientId`	Known user identity (set by your application or the client tracker)
`rlvt_tmpId`	Anonymous visitor ID (set automatically by the script or SDK middleware)

Priority: rlvt_clientId > rlvt_tmpId. If neither exists, the script or SDK middleware generates a new rlvt_tmpId automatically.

Getting Started

Web Integration

Mobile Integration

Guides

Datasources API

Contents API

Workflow API

Datasources Collector

Overview

Reelevant Client Side Script

Reelevant Server Side SDK

Reelevant as API (JSON)

When to use which

Content types

Identity management

​Overview

Reelevant Client Side Script

Reelevant Server Side SDK

Reelevant as API (JSON)

​When to use which

​Content types

​Identity management

Overview

When to use which

Content types

Identity management