Freelancer profile translated to English.
Back to original languageAbout Sébastien
Tech Lead with a strong Product and Business culture, I combine historical technical expertise (Symfony/Node.js) with a strategic vision of Fractional CTO. My role is to translate your business challenges and client needs into pragmatic, scalable, and performant technical solutions.
I bridge the gap between the vision of leaders, the expectations of Product (PM/PO), and technical reality.
Why work with me?
Product & Business Culture: My priority is the value delivered to the user. I immerse myself in your KPIs and customer journeys so that every architectural choice directly serves your growth.
Tech Leadership & Pragmatism: A follower of DDD and Clean Architecture, I faithfully model your business processes and guide teams towards efficient delivery.
Modernization & Modern Engineering: Expert in technical debt reduction. I integrate modern tools (automation, AI opportunities) to accelerate delivery without sacrificing stability.
My Areas of Intervention
1. Product, Business & Tech Lead Alignment
Business-to-Tech Translation: Co-design of features with Product, backlog prioritization according to ROI.
Architecture & APIs: Business modeling (DDD), robust APIs (Symfony, NestJS), and maintainable code.
2. Modernization & Scalability
Audit & Refactoring: Diagnosis of technical debt, modernization of aging stacks without service disruption.
Ops & Data: Docker, CI/CD (GitHub, GitLab), and database optimization to handle load.
3. Pragmatic Innovation & Efficiency
Smart Features: Integration of AI components (LLM, automation) where they bring business value.
Team Tooling: Optimization of development processes to reduce Time-to-Market.
Long-Term Vision
My longevity in my previous assignments demonstrates my reliability and my ability to support your long-term growth.
French
Native or bilingual
English
Fluent
Can work on-site
Marseille (up to 30km), Aix-en-Provence (up to 10km)
Experience
- Airbus HelicoptersDeveloperDEFENSE AND MILITARYJune 2025 - Today (1 year and 2 months)Vitrolles, France
Development of an Industrial Intelligence (BI & Reporting) platform.
The challenge: Ensure the reliability, traceability, and analysis of massive data flows for the management of aeronautical production (High Availability).Strategic Achievements:
**Data Engineering & Query Builder**: Design of a dynamic search engine for generating custom queries. Modeling of high-performance data schemas to transform raw data into indicators.**Temporal Analysis System (Data Diff)**: Development of an innovative module for comparing industrial states. Implementation of a snapshot logic to identify deltas (additions, modifications, deletions) in real-time over long production cycles.**Validation & Integrity Algorithms**: Creation of an advanced validation software layer (Data Quality). Deployment of algorithms to ensure data compliance, eliminating any risk of analysis errors.Real-Time Infrastructure: Implementation of a push notification system via WebSockets / Mercure, ensuring immediate responsiveness of operational teams to critical alerts on the production line.Technical Expertise:
- Backend: PHP 8, Symfony.
- Frontend: Angular (Interactive dashboards and data visualization).
- Data & Ops: Neo4J, Advanced SQL (execution plan optimization), Complex algorithms, Docker, CI/CD.
- SONERGIAFullstack DeveloperMarch 2022 - Today (4 years and 5 months)Marseille, France
API Architecture & ERP Connectivity
Transformation of the information system through an API-First architecture.**Challenge**: Centralize and expose internal ERP business data to enable interoperability with third-party services and modern interfaces.**Achievements**:- Design of a scalable REST API using Laravel. The goal is to digitize the core application of an internal ERP.
- Development of a React administration interface.
Stack: Laravel, React, Eloquent ORM, Redis, Docker.Energy Premium Calculation Engine
Digitization of complex business rules and automation of regulatory processes.**Challenge**: Ensure the accuracy of calculations for renovation aid (MaPrimeRénov', CEE) by integrating constantly changing and complex regulatory variables.Achievements:- Development of a high-precision calculation engine using Symfony, capable of interpreting complex decision trees based on beneficiary profiles.
- Design of a dynamic user journey in React (complex conditional forms) for audit data entry.
- Guarantee of data integrity and implementation of unit tests (PHPUnit) to validate the compliance of calculations with legal requirements.
Stack: Symfony, React, PostgreSQL, PHPUnit, Workflow Component. - FreelanceFullstack DeveloperJanuary 2013 - Today (13 years and 7 months)Aix-en-Provence, France
Fullstack Expert Consultant & Tech Trainer
Strategic support and realization of complex business solutions.The challenge: Intervene in various ecosystems to design tailor-made tools, while transmitting best practices for senior development (Clean Code, Design Patterns).Notable Achievements:
**Industry & ERP (STMicroelectronics, Entre Marchands Auto)**:Design of industrial modeling software and an automotive ERP.Focus on complex domain modeling and transactional flow optimization.High-Audience Platforms (Inzejob, Marketplaces):Development of a job offer application and matchmaking solutions.Implementation of scalable architectures with Symfony and high-performance user interfaces with React.HR & Management (Inzejob):Creation of human resources management tools centralizing employee data and administrative processes.Knowledge Transfer & Mentoring (Ynov):Leading software development training sessions.Mentoring emerging talent on industry standards (Git, CI/CD, Testing).Technical Expertise:
Frameworks: Symfony (Backend Expertise), React (Responsive Interfaces).Methodologies: Agile, Code Audit, Skill Transfer.
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Education
- Information and communication technologiesAix-Marseille University