Available for freelance projects

Sylvain Tissier builds products and companies.

Fullstack developer, founder & consultant — Paris, France

I build SaaS products and AI-era tools, and help teams with anti-hype automation consulting — measured in ROI, not slideware. Previously a Web3/blockchain consultant; that work lives in the archive now.

Current ventures

6 active

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, 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. Immutable history, full export, 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 — 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 ↗

The book

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

New book

Learn AI Now or Fall Behind

Practical workflows to stay relevant at work — by Sylvain Tissier

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
  • Prove value with evidence
“AI doesn't replace standards. It multiplies them.”

Édition française : « Adoptez l'IA maintenant ou restez derrière ».

Writing & contributions

Essays on Medium, and contributions to the open-source book Mastering Ethereum by Andreas Antonopoulos.

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

What clients say

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

Brian LeeClient

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