Context

Construction tradespeople in France operate in a dense regulatory environment: e-invoicing, multi-rate VAT, legal warranties, subcontracting rules, self-employed contributions — each area has its own rules, thresholds, and deadlines. Most available resources are either too generic or buried in unreadable official texts.

Kalceo started from a simple need: give construction tradespeople direct access to the information they need, at the right moment, without unnecessary jargon. What began as a 2026 e-invoicing-compliant quote tool has evolved into a compliance and operational platform for construction artisans and small businesses.

What Kalceo does

Practice sheets

A library of 39 short practice sheets (~2 min read) covering the key topics of running a trade business: invoicing, regulations, HR management, legal warranties, subcontracting, unpaid invoices. Each sheet addresses one specific point with figures updated for 2026.

Free calculators

Four online calculation tools available without sign-up:

  • Artisan retirement 2026 — pension estimate based on the SSI scheme
  • Late payment penalties — amount owed + flat €40 indemnity
  • Construction VAT — applicable rate (5.5%, 10%, or 20%) based on the type of work
  • Tiling calculator — tile quantities, adhesive, and grout for a given surface

New calculators published each month.

Long-form blog

In-depth analyses on the legal and management topics that matter to tradespeople: two-year warranty, right of withdrawal, dispute resolution, hourly pricing, e-invoicing platforms, MaPrimeRénov'. Content distinct from the practice sheets, aimed at understanding rather than quick reference.

Trade hubs

Thematic verticals grouping all relevant resources by trade — practice sheets, calculators, quote templates. The Tiler hub is live. More trades are being added progressively.

Tech stack

Kalceo runs on a deliberately simple architecture:

  • Static HTML — no server-side framework, instant rendering, zero runtime dependencies
  • Tailwind CSS — utility-first layout, minimal build output
  • Cloudflare Pages — global edge hosting, native HTTPS, continuous deployment from Git
  • Cloudflare Functions — server-side forms (newsletter, lead magnets, transactional email) without dedicated infrastructure

The static-first approach is foundational: documentary content, fast deployment, near-zero marginal cost. Cloudflare Functions handle the handful of interactions needed without sacrificing that simplicity.

In production

Kalceo is live at kalceo.fr. Content evolves at the pace of regulatory updates and new tool releases.