Products shipped, running in production.

A selection of freelance projects, from custom development to code audits. Different industries, different challenges, the same standard: ship a solid product, used by real users.

01CMA CGM

Case studies

Different contexts, one method.

Each project starts from a concrete problem: collecting payments, keeping up with real time, modernizing legacy code, auditing an application in production. Here is what was built.

Shipping · Logistics

CMA CGM, one of the world's leading shipping companies, plans its cargo ship routes on a global scale. A complex business domain, critical data, and an application used daily by planning teams.

A global-scale group$54.4B in revenue in 2025160,000 employees

What I did

Frontend lead developer of a team of 3 people
Application for managing cargo shipping route planning
Frontend development in ReactJS

Stack

ReactJSFrontend lead

“Sébastien is experienced, very curious and a great listener. His feedback as a freelance also helped me approach projects differently. I really enjoyed working alongside him and recommend him without hesitation.”

Ariane SpanneutFull Stack Engineer, ex-Coding Factory Squad

Recommendation on LinkedIn

Marketplace · Community shipping

Cocolis connects senders with travelers already making the trip. To secure peer-to-peer transactions, the platform needed credit card payments built right into its ordering flow.

700,000users

10,000merchant partners

What I did

Implemented the online credit card payment system
Built the custom payment interface in ReactJS
Integrated it into the existing ordering flow

Stack

ReactJSNextJSOnline payments

“I had the chance to work with Sébastien on a React/Next.js application, and everything went extremely well. Available, friendly and skilled, Sébastien has all the qualities to help you out!”

Sébastien FielouxFreelance Ruby on Rails / Magento 2

Recommendation on LinkedIn

Professional training · Microsoft Teams

Doxa wanted to extend its training beyond the classroom: deliver learning capsules to students directly in Microsoft Teams, then measure what they retain.

649training sessions per year

5,483people trained per year

What I did

Built the Teams app that delivers learning capsules to students
Built the back office to manage and schedule capsule delivery
Integrated AI to analyze participants' answers

Stack

Microsoft TeamsAIBack office

Trustpilot

“Sébastien is extremely efficient and rigorous. The project was led with great clarity and excellent structure. The work delivered is of very high quality. I will work with him again without hesitation on my next projects.”

Jon MandelDoxa Formation, training organisation

Verified review on Trustpilot

Entertainment · Real time

A blind test game played simultaneously on mobile, TV and tablet. The legacy backend could no longer keep up with the product's real-time and gamification ambitions.

As seen on televisionFeatured on “Qui veut être mon associé ?”

1M+players

11private venues

What I did

Rebuilt the entire backend in clean architecture with NestJS
Real-time synchronization across the mobile, TV and tablet apps
Gamification mechanics at the heart of the game experience
Reinforcement on the NextJS / ReactJS frontend

Stack

NestJSNextJSReactJSReal time

Industry · Sorting machines

Pellenc ST designs intelligent sorting machines for the recycling industry. Its legacy Qt C++ applications needed to move to modern web interfaces.

An international manufacturer€85M in annual revenue250 employees

What I did

Provided expertise for migrating Qt C++ applications to ReactJS
Built the frontend of a sorting machine monitoring application

Stack

ReactJS.NETMonitoring

Founder

Food service · SaaS

Independent restaurants need to sell online without depending only on the big platforms. I founded Circlee to give them their own ordering channel, and I still run it in production.

Production impact100,000+ online orders processed83,000+ bank transactions

What I did

Built a complete SaaS online ordering solution
Delivery and click-and-collect ordering flows
Admin space to manage menus, orders and promotions

Stack

SaaSReactJSNextJSJava

Circlee

“Circlee has been a game changer. Our orders were stagnating and our customers kept voicing their frustration with our website's usability and the lack of certain payment methods.”

Yvan M.Co-founder of Gouste · orders ×2.7 in 18 months with Circlee

Customer story published on circlee.fr

TCract

Surveying · 3D visualization

TCract publishes IZItopo Viewer, a platform for visualizing and sharing 3D point clouds for surveying professionals. The team wanted an outside look at the technical health of the application.

3D visualization startupBentley Systems partner

What I did

Audited the code of the IZItopo Viewer application
Analyzed the architecture, code quality and security
Delivered a prioritized action plan

Stack

Code audit3D visualization

What's next

Your project could be the next one.

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