01 Introduction

I build products and companies, without the hype.

Sylvain Tissier — fullstack developer, founder & consultant based in Paris, France. I design and ship SaaS products and AI-era tools, and help teams automate what actually pays off. Previously a Web3/blockchain consultant — that era now lives in the archive.

Available for freelance projects

02 Current ventures

Six things I'm building right now

Products and services I own and run — from AI developer tooling to anti-hype automation consulting.

Polystro

Live · Early access

The workspace built for AI-driven development. Run Claude, Codex, Gemini and other CLI agents in parallel across projects — each with isolated ports, browser identities, terminals and git worktrees. Desktop app for macOS, Windows and Linux.

Electron · React · Convex

polystro.com

NodiumLabs

Live

Anti-hype automation ROI consulting for operations teams. Most agencies sell hype — we sell math. Measure ROI first, start small, and scale only what proves 3x+ returns.

Astro · Cloudflare

nodiumlabs.com

Fox Close Pipeline Lab

Live

A CRM intelligence layer that tells sales teams which deals can really sign: deterministic Deal Confidence Score, pipeline confidence map, and fragile-deal detection.

TanStack Start · Convex · Cloudflare

foxcloselabs.com

Notarium

Building

A system of record for knowledge. Capture, structure and retrieve information you can trust months later — with immutable history, full export, and no lock-in.

Next.js · AdonisJS · PostgreSQL

notarium.app

Sancterius

In development

A SaaS for French condominium property managers (syndics de copropriété): per-building accounting, appels de fonds, general assemblies, supplier invoices with AI extraction, and owner portals.

TanStack Start · Fastify · PostgreSQL

sancterius.com — coming soon

SaaS Backbone

In development

A production-ready, self-hostable SaaS foundation: auth (MFA, OAuth, SSO, RBAC), multi-tenant teams, billing (Stripe, Paddle, Polar), admin back-office, and a plugin marketplace.

Next.js · AdonisJS · PostgreSQL · Stripe

saas-backbone.com — coming soon

03 The book

Book cover — Learn AI Now or Fall Behind, by Sylvain Tissier

Learn AI Now or Fall Behind

Practical workflows to stay relevant at work — by Sylvain Tissier

French edition: « Adoptez l'IA maintenant ou restez derrière »

Most AI advice is hype or prompt lists. This book teaches workflows — how to turn AI into leverage without sacrificing quality: pick the right execution model per task, install trust gates so “fluent wrong” never ships, build reusable assets that compound, and prove value with evidence.

AI doesn't replace standards. It multiplies them.

04 Writing & contributions

Things I've written

Long-form posts on Medium, plus contributions to a book that taught a lot of people Ethereum.

Contributor to “Mastering Ethereum” (Andreas Antonopoulos) — privacy-enhancing patterns, upgradability patterns, and gas refunds.

05 Archive

Earlier work, kept for the record

LinkedTeam — social website for teams· Fox Close — the first solution dedicated to the closing of sales (original version)· BitFunding — open-source crowdfunding platform using Bitcoin· MoneyUnion — landing page for a Bitcoin remittance company· Ethereum ↔ Hyperledger bridge — proof of concept

06 Kind words

What clients say

From recent freelance engagements.

He is really nice. He knows what we want, gave us useful suggestions. Good communication, and it looks great! Thanks for the work.

Brian Lee — client

Une implication et une organisation projet bien structurée et conforme aux engagements… Prestation d'une grande qualité d'ensemble et respect des engagements.

Jean-Marc Reynaud — client

07 Contact

Have a project in mind?

I'm available for freelance projects — product builds, AI-era tooling, or automation that has to pay for itself. Let's talk.

Get in touch on LinkedIn