Our stack — nothing to hide

Mature ecosystem, concurrent rendering for smooth transitions.

Compile-time safety, stress-free refactoring, self-documenting code.

Instant HMR in development. Since v8, the bundle is produced by rolldown and minified by oxc — esbuild has left the dependency tree.

Declarative API, routes loaded on demand, Suspense-compatible.

Zero runtime, automatic purging, visual consistency guaranteed by tokens.

Copied into the repo — no fragile library dependency, 100% of the code under our control.

Correct ARIA out of the box, keyboard navigation, focus trapping.

Declarative API, respects prefers-reduced-motion, GPU compositing.

Tree-shaken, consistent style, 1,500+ maintained icons.

Every route on the site — service pages, local pages and the 37 portfolio case studies — is rendered at build time in headless Chromium. Previously the server returned the same empty index.html for all of them: crawlers that don't execute JavaScript only saw the home page's metadata.

LCP, INP and CLS measured on real users, sent to GA4.

Self-hosted Outfit + Plus Jakarta Sans, Latin subset, font-display: optional.

Separate vendor chunks (react, motion, radix, pdf) → optimal long-term caching.

Title, description and Open Graph specific to each page.

Organization, LocalBusiness, Service, FAQPage, HowTo, BreadcrumbList, Article.

A file dedicated to indexing by ChatGPT, Claude, Perplexity and Gemini.

Generated at build time from the routes declared in App.tsx — it can never fall behind the site.

Managed Postgres, Auth, Storage, Edge Functions — open source.

Receives contact form messages, relayed by a Vercel serverless function.

Delivers the configurator's PDF quotes via a Supabase function. No IP filtering on the API side.

Typed schemas shared between client and server, French-language error messages.

Deploy on git push, global CDN, HTTP/3, preview branches.

kayzen-lyon.com and .fr domains, DNS zone and email.

Code review and full history — it is what feeds the public changelog.

Strategic asset caching, /offline.html fallback page.

Shares Vite's configuration, so the same aliases and the same pipeline as in production.

Critical user journeys replayed on Chromium (desktop) and on a Pixel 7 mobile profile.

script-src without 'unsafe-inline': every inline script is allowed by its SHA-256 hash, checked at build time.

2-year max-age, includeSubDomains, Chrome preload registry.

Camera, microphone, USB and geolocation disabled by default.

Consent Mode v2, denied by default, GA4 loaded only after explicit consent (no GTM), named data processors.

Strict rules, hooks checks, blocking in CI.

Visual inspection of chunks, detection of heavy imports.

Autoprefixer, compatibility with modern browsers (es2020+ targeted).

package-lock.json is the source of truth, and it is what Vercel installs on deployment.