Senior Full-Stack Software Engineer

📍 Paris | 💼 CDI | 🎛️ Senior Full-Stack Engineer at Fairglow | 🧩 Core Architecture & Scale | 🔗 Report direct to CTO 🗣️ English required; French preferred 🌱 About Fairglow Fairglow is building the next generation ecodesign software for the cosmetics industry. Our SaaS platform helps brands measure and reduce the environmental impact of their products — from raw ingredients to packaging — using the power of Life Cycle Assessment (LCA). We combine data science, sustainability expertise, and intuitive UX to bring LCA out of the consulting world and into the hands of decision-makers. 🛠️ About the Role We’re looking for a Senior Full-Stack Software Engineer to help shape the core architecture and roadmap of our product. You’ll work across the stack — building robust features, managing scalable systems, and helping bring scientific data to life through powerful interfaces. This is a key role on a small, high-trust team. You’ll be involved in everything from architecture and implementation to troubleshooting and client feedback loops. We’re looking for someone who’s experienced, pragmatic, and excited to build meaningful tools that support sustainability. ✅ What You’ll Do Develop and maintain features across the stack (TypeScript, React, Python, FastAPI, databases) Help define and evolve our product architecture, data pipelines, and deployment processes Set and uphold quality standards across codebases, testing, and documentation Effectively manage offshore development resources and integrate their contributions Leverage AI-assisted tools to accelerate development and improve productivity Collaborate closely with product, science, and sales teams to deliver features that users love Participate in client-facing projects, with occasional debugging and problem-solving support 📆 First 30 Days Onboard to the product, tech stack, and core LCA workflows Ship improvements and fixes while learning project architecture Join client conversations to understand real-world usage and edge cases 📈 First 90 Days Lead architectural improvements to support scale and flexibility Establish dev workflows that support efficient use of offshore and AI resourcesYou Contribute significantly to a key product milestone or launch Collaborate cross-functionally to scope and design impactful new features 💚 Why Join Us? At Fairglow, you’ll work on real problems that matter — helping top cosmetic brands reduce their environmental footprint. You’ll join a small, high-impact team with the autonomy to make decisions, build fast, and leave your mark on a meaningful product. 🧩 Who You Are 7+ years of experience in full-stack development Strong front-end experience with TypeScript and React Comfortable building and maintaining backend systems in Python (FastAPI or similar) Experience managing or working with offshore development teams Familiarity with AI-assisted development tools and workflows Pragmatic problem-solver who balances clean code with delivery Passionate about sustainability, climate tech, or purpose-driven software Fluent in English; French is a strong plus 🚀 Your impact at Fairglow Scale the platform: You will transition the product from an MVP state to a scalable, enterprise-ready SaaS architecture. Elevate quality: You will establish the engineering standards (code reviews, testing, documentation) that allow us to integrate offshore work without sacrificing quality. Empower users: You will build the features that turn complex environmental data into actionable insights for decision-makers. Build the foundation: You will lay the technical groundwork (tooling, processes) for the future internal engineering team. What we offer Compensation: 50–65 K€ / year depending on profile + benefits. Perks: Lunch vouchers (Swile), Top-tier health insurance (Alan), 50% transport coverage, afterworks, and a new Mac. Contract: Full-time (CDI). Location: Paris 10th (Rue du 8 Mai 1945). #J-18808-Ljbffr