Senior Fullstack Software Engineer at Vizzia

🎯 MISSION Today, one engineer owns the entire Safety and VMS stack. The roadmap is loaded: a UK videoverbalization MVP due in June 2026, a France rollout in Q4, a live videoverbalization feature in Q1 2027 — all running in parallel, all critical. That's not a backlog problem. It's a capacity problem. Vizzia has grown from €4M to €9M ARR and is on its way to €30M, now serving 200+ local authorities across France and the UK. Our Safety platform is at the core of that growth — and the frontend needs to be built from scratch, on a solid architectural foundation, before the next wave of clients lands. You'll join a small, focused team: Jeremy (Staff Engineer, your direct lead), Jean-Baptiste (Cloud Engineer), Hadrien (PM), and Walid (Designer). The team is intentionally lean — and will stay that way. Your mission: become Jeremy's technical partner, architect the Safety code base from the ground up, and make sure the roadmap ships on time. 🛠️ WHAT YOU'LL DO 1. Build the Frontend from Scratch The mockups are in progress. The stack is defined. What's missing is the person who will turn this into a scalable, maintainable product. - Architect and build the Safety SaaS frontend using React 19, Vite, TypeScript, Tailwind CSS v4 - Co-design and maintain the design system with Walid — tokens from Figma, components in shadcn/ui, documented in Storybook - Implement state management (Zustand), server state (TanStack Query), forms (React Hook Form), and i18n (i18next) in a coherent, well-structured way - Build a custom video player (MediaBunny/MOQs/WebRTC) and handle video streaming requirements 2. Deliver a Critical Roadmap - Ship the UK videoverbalization MVP in production by end of June 2026 - Contribute directly to the France rollout (Q4 2026) and live videoverbalization (Q1 2027) - Size tasks reliably and flag blockers early — no surprises at sprint review 3. Own Code Quality - Maintain unit test coverage above 85% on all code you touch - Set up and maintain end-to-end tests with Vitest & playwright across the full application - Write PRs that are readable without a deep dive — clear scope, clean diffs, useful context 4. Co-architect with Jeremy - Make joint decisions on architecture, patterns, and technical direction — not just execute - Challenge Jeremy's choices constructively, and expect the same in return - Take ownership of technical decisions and stand behind them, with arguments 5. Set the Foundation for the Team - Document conventions, contribution rules, and architectural decisions from day one - Intervene on the backend (Node.js, Hono, Drizzle ORM) and infra (Docker, K8s, Helm, CI/CD) when needed — at least enough to never be blocked - Onboard the 1–2 engineers joining in 2027 and become the natural technical reference - ✅ WHO YOU ARE - You have 5+ years of experience, including meaningful time in a fast-paced SaaS or scale-up environment — and you've built (or significantly structured) a product from scratch - You are an expert in modern React and its ecosystem: Zustand, TanStack Query, React Hook Form, advanced hooks, performance patterns — your state management choices are justified, not defaulted to - You've shipped a scalable frontend architecture before: design system, component library, reusability patterns — and it was still being used 18 months later - You have solid Node.js / TypeScript fundamentals — enough to own the full stack when needed, not just the client side - You actively use AI coding tools (Cursor, Claude Code, Copilot) to move faster without compromising quality - You don't wait for perfect specs. You challenge the PM and designer when something doesn't make sense — with arguments, not ego. You're the kind of engineer who makes the team around them better, not just the codebase. An engineering degree is required for this job BENEFITS 🏡 Hybrid work 🏝 Contrat cadre and RTT (between 8 and 12 days per year depending on public holidays) 💻 A Mac or PC depending on your preferences 💸 BSPCE 🍜 60% coverage of meal vouchers worth €9 per worked day 🚃/🚲 Sustainable mobility allowance 🏥 Mutuelle (Alan) 💼 Offices located in central Paris (9th arrondissement) ☀️ Annual offsite with the whole team and plenty of company events RECRUITMENT PROCESS 1. Video call with Talent Acquisition 2. Hiring Manager interview + culture fit with Jeremy (Hiring Manager) — 45 min 3. Technical case study — frontend & backend 4. Team interviews — PM, Designer, Cloud Engineer 5. Final interview with CTO