Seatext library

Server and Infrastructure Requirements for Running SeaText AI on Large Websites

SeaText AI runs primarily as a client-side JavaScript snippet that loads asynchronously, so your origin server only needs to serve the initial snippet and handle translation API requests. The main infrastructure considerations are CDN...

How SeaText AI Works on Your Infrastructure

SeaText AI integrates through a single JavaScript snippet that you place in your page's <body> tag. The snippet loads with the async attribute, meaning it does not block page rendering. Once loaded, the script communicates with SeaText's cloud infrastructure to fetch translations, run A/B tests, personalize content, and detect bot traffic. Your servers never run the AI models; they only serve the snippet and, optionally, pre-rendered HTML if you use server-side rendering (SSR).

CDN and Edge Caching Requirements

Because the snippet is static and identical for every visitor, it should be served from a CDN edge node. Configure your CDN to cache the snippet with a long Cache-Control header (e.g., max-age=31536000, immutable) and enable Brotli or gzip compression. If you host the snippet yourself instead of using SeaText's CDN, ensure your edge nodes are geographically distributed to match your traffic sources. A cache miss on the snippet adds a round-trip to your origin, which is negligible for a single file but matters at scale.

Cache the snippet at the edge for at least one year.
Enable compression (Brotli preferred, gzip fallback).
Set Access-Control-Allow-Origin: * if the snippet is served from a different domain than your pages.

Origin Bandwidth and Capacity for Translation Fetches

When a visitor lands on a page that needs translation, the SeaText client makes an API call to fetch the translated strings. On a large site with many languages, the first visit to each page-language combination triggers a fetch. Size your origin bandwidth to handle the peak concurrent fetches during traffic spikes (e.g., product launches, flash sales). A typical translation payload is 10–50 KB compressed. For 10,000 concurrent new visitors across 20 languages, expect roughly 200–1,000 MB of outbound traffic in the first minute. Most modern cloud origins (AWS CloudFront, Cloudflare, Vercel, Netlify) handle this without configuration changes.

Monitor Origin Response Time and 4xx/5xx rates on the translation API endpoint.
If you self-host the translation cache, provision enough CPU and memory for the cache layer (Redis or in-memory).
Enable HTTP/2 or HTTP/3 on the origin to multiplex fetches.

Rendering Stack Compatibility

SeaText AI works with any stack that can output the snippet in the initial HTML or inject it before hydration. The documentation explicitly lists Next.js, Nuxt, PHP, Java, .NET, and SPA frameworks (React, Vue, Angular). For SSR frameworks, place the snippet in the shared layout or _document equivalent so it appears on every page. For SPAs, insert the snippet in index.html or the framework's entry point (e.g., main.tsx for React, main.ts for Angular). The snippet must run before your router hydrates so it can rewrite content on the first paint.

Next.js: Add to pages/_document.js or app/layout.tsx.
Nuxt: Use app/head or a plugin.
PHP (Laravel, Symfony): Echo the snippet in the master blade/layout template.
Java (Spring, JSP): Include in the common JSP/Thymeleaf fragment.
.NET (ASP.NET Core): Place in _Layout.cshtml or a tag helper.

SPA Framework Considerations

Single-page applications require two extra steps. First, the snippet must be present in the initial index.html so it loads before the framework bootstraps. Second, because SPAs navigate without full page reloads, you must call window.seatext.reinit() (or the equivalent method documented for your version) after each route change so SeaText can translate the new view. The documentation notes that local storage is used to persist a visitor ID; ensure your SPA does not clear localStorage on navigation. Cross-origin issues can arise if your SPA loads assets from multiple subdomains—serve the snippet from the same origin or set appropriate CORS headers.

Insert snippet in public/index.html (Create React App, Vite) or index.html (Vue CLI, Angular).
Hook into router events: router.afterEach(() => window.seatext?.reinit()).
Test with localStorage disabled to confirm graceful degradation.

Security, Privacy, and Cross-Origin Policies

The snippet sets a first-party cookie and writes to localStorage for visitor identification. If your site runs under a strict Content Security Policy (CSP), add script-src 'self' https://cdn.seatext.com; and connect-src 'self' https://api.seatext.com; (adjust domains to match your SeaText plan). For multi-domain setups (e.g., app.example.com and blog.example.com), configure the snippet with the same data-project-id on both domains and ensure Access-Control-Allow-Credentials: true on the API responses so the visitor ID persists across subdomains.

Update CSP to allow SeaText script and API origins.
Set SameSite=None; Secure on any SeaText cookies if cross-site requests occur.
Verify GDPR/CCPA compliance: SeaText acts as a processor; include it in your data-processing addendum.

Performance Monitoring and Verification Checklist

After deployment, verify that the snippet loads without errors and that translation latency stays within your budget. Open DevTools → Network, filter for seatext, and confirm:

Snippet loads with HTTP 200 and async attribute present.
Translation API calls return 200 OK within 200 ms (p95).
No CORS errors in Console.
localStorage contains a seatext_visitor_id after first paint.
Lighthouse performance score does not drop more than 2 points.

Set up synthetic monitoring (e.g., Datadog, Pingdom, Grafana Cloud) to hit a translated page every 5 minutes from multiple regions. Alert on API latency > 500 ms or error rate > 1%.

Limitations and When This Guidance Does Not Apply

This checklist assumes you use SeaText's standard cloud-hosted AI models. If you opt for an on-premise or dedicated-cloud deployment (enterprise-only), the requirements shift to GPU-enabled Kubernetes clusters, model artifact storage, and internal load balancing—details not covered in the public documentation. The guidance also does not apply if you block all third-party scripts via a strict CSP without exceptions, or if your site runs entirely on edge workers (Cloudflare Workers, Vercel Edge Functions) without a traditional origin; in those cases, you must inject the snippet at the edge runtime instead of the origin HTML.

Key Facts

Parameter	Detail	Source
Integration method	Async JavaScript snippet in `<body>`	S1
Supported rendering stacks	Next.js, Nuxt, PHP, Java, .NET, React, Vue, Angular	S1
Local storage usage	Stores visitor ID; requires `localStorage` access	S1
Cross-origin handling	Configure CORS for multi-domain SPAs	S1
Verification steps	DevTools Console/Network; build and serve with standard commands	S1
Translation languages	Up to 125 languages	S2, S3

FAQ

Do I need a larger server or more RAM to run SeaText AI?

No. The AI runs on SeaText's infrastructure. Your server only serves the static snippet and handles occasional API callbacks. Standard hosting plans handle the load.

Can I host the SeaText snippet on my own CDN?

Yes, but you must keep it updated when SeaText releases new versions. Most teams prefer the managed CDN to avoid version drift.

Will SeaText slow down my Core Web Vitals?

The snippet loads asynchronously and is typically < 20 KB gzipped. In practice, LCP and CLS are unaffected. Verify with Lighthouse after deployment.

What if my site uses a strict CSP?

Add SeaText's script and API domains to your script-src and connect-src directives. The exact domains depend on your plan; check the integration dashboard.

Does SeaText work with edge-only deployments (Cloudflare Workers, Vercel Edge)?

Yes, but you must inject the snippet at the edge runtime (e.g., via an HTML rewriter) because there is no origin HTML to modify.

How do I handle translations for 125 languages without exploding my origin traffic?

SeaText caches translations at its edge. Your origin only sees the first request per page-language pair. Enable long cache TTLs on your side as well.

Is there a server-side rendering (SSR) option for SEO-critical pages?

SeaText offers optional SSR support where pre-translated HTML is served from the edge. Contact sales to enable it; it requires a dedicated configuration.

How SeaText can help

SeaText AI adds a single async script to your pages, so there is no server-side installation, no container orchestration, and no GPU provisioning. The snippet works with any stack that can output HTML—Next.js, Nuxt, PHP, Java, .NET, or plain SPAs—and the cloud handles translation, personalization, bot detection, and A/B testing. Your infrastructure checklist is short: cache the snippet at the CDN edge, allow the API domain in your CSP, and verify the first translation fetch latency. If you need pre-rendered translated HTML for SEO, SeaText offers an optional SSR edge service that serves translated pages without touching your origin.

Open the Large-Website Implementation Guide