Senior Fullstack Engineer - Freelance

We are bsport. The place to be!

bsport is an all-in-one platform combining boutique fitness and advanced technology. Our platform helps our partners manage their bookings, payroll, marketing and more, to streamline operations and boost their commercial success.

Since we launched in 2019, we have already achieved the following:

• We’ve built a community of over 7 million users 🤝
• In December 2024 we have finalised the biggest Series B (€30 million)🏆
• Grown our team to more than 200 employees 🚀

We’re continuing to grow to become the #1 tech partner for boutique studios in Europe and the rest of the world!

Join us to write the next chapter of your career!

About the role:

Take ownership of major frontend initiatives, help lead complex technical projects, and work directly with leadership to define the future of our platform. You’ll help us address technical debt, a complete revamp of our client interfaces, build and maintain our in-house design systems, and build scalable solutions for one of our product verticals.

Our focus for the coming years is building reliable and scalable systems, and setting a new standard for technical excellence.

What You'll Work On

Roughly 70% of your time — front-end / back-office revamp:

• Own the revamp of key back-office pages and features within the Booking scope (list and detail views, member profiles, establishment pages, teacher tools…)
• Implement interfaces from high-fidelity prototypes delivered by our dedicated designer
• Write clean, tested React (TypeScript) code aligned with our internal design system
• Collaborate with internal engineers to ensure long-term maintainability

Roughly 30% of your time — backend support for the revamp:

• Evolve and adapt the backend logic that powers the revamped front-end features (APIs, data models, business rules)
• Ensure the back-office pages you're rebuilding are fully supported end-to-end — not just visually, but functionally
• Work closely with internal backend engineers to align on contracts, flag dependencies early, and unblock front-end delivery

Tech stack

• Front-end: React (TypeScript), Zustand, styled-components, internal design system
• Back-end: Django, Postgresql, AWS, Kubernetes
• Language-agnostic mindset: we care more about strong engineering principles than specific tools. That being said, a ground level in Python / postgresql is expected

Practical details

• Duration: 6 months (Q2–Q4 2026), with possible extension
• Pace: Full time (5 days/week)
• Location: Remote setup possible, office in Paris 10e

Who We're Looking For

• 5+ years of full-stack experience, with genuine front-end depth in React (TypeScript)
• Solid backend skills in Python (Django or FastAPI), comfortable with high-volume systems
• At ease in a hybrid role — able to deliver polished UI and review a backend PR in the same day
• Informal technical leadership: you share feedback in code reviews, document decisions, and help others grow
• Strong written communication skills in English
• Background in a startup or scale-up, ideally B2B SaaS

What This Mission Offers

• A varied mission with direct product impact in the short and medium term
• A modern stack
• A high-growth context with an engaged team and strong engineering standards