Freelancer profile translated to English.

Description

Is your backend slowing down your growth? Are your APIs not scaling, or is your tech team overwhelmed and you need operational senior reinforcement quickly?

I'm Sébastien, a backend engineer with 5 years of experience in production at Diffusely (formerly Meero), a SaaS company specializing in large-scale image processing.

What I bring concretely:

- Maxio → Stripe migration in production: zero downtime, all client subscriptions migrated without error, 35% cost reduction

- High-performance REST API architecture and development with FastAPI and Symfony, serving millions of requests

- AWS serverless deployments (Lambda, ECS, ECR, S3, DynamoDB) and automated CI/CD pipelines with GitHub Actions + Docker

- Integration of complex external APIs (Stripe, Nexrender, Runware) and business workflow automation

- Integration of LLM APIs (OpenAI, Anthropic) into existing backend architectures: AI-augmented workflow automation, production deployment, and monitoring

My profile:

Coming from haute cuisine (12 years in professional kitchens, Michelin-starred restaurants), I made a deliberate choice to retrain as a developer. This background taught me one thing: to deliver under pressure, without a safety net, with a rigor that allows no room for error. This is exactly what I bring to your backend projects.

I work remotely from Nîmes, available for technical reinforcement missions, architecture redesigns, API integration, AI automation, or migration support.

Do you have a backend project, technical debt to resolve, or need a reliable developer for a short or long mission? Let's talk.

Industry field of expertise

Languages

French
Native or bilingual
English
Fluent

Workplace preferences

Can work on-site

Paris (up to 10km), Nîmes (up to 20km), Montpellier (up to 20km)

Diffusely
Backend Engineer — Python · PHP · Golang · AWS
SOFTWARE PUBLISHING
October 2021 - March 2026 (4 years and 5 months)
Paris, France
Backend engineer within an image processing SaaS company (B2B, international). Development and maintenance of REST APIs in FastAPI (Python) and Symfony (PHP), microservices architecture, AWS deployments.
Key achievements:
— Complete migration of the payment provider (Maxio → Stripe): 0 downtime, 100% of subscriptions migrated, -35% operational costs
— Development of a serverless media archiving system (AWS Lambda + S3) handling large volumes
— Integration of complex third-party APIs (Stripe, Nexrender, Runware) for workflow automation
— Setup of a complete CI/CD pipeline (GitHub Actions + Docker) with semantic versioning and automated deployment
— Unit and integration tests (PHPUnit, Behat)
Python GO PHP Amazon Web Services Microservices
Openclassrooms
WEB DEVELOPER APPRENTICESHIP
SOFTWARE PUBLISHING
February 2021 - August 2021 (6 months)
Paris, France
Gained proficiency in HTML5, CSS3, and JavaScript for web development.

Learned to use modern frameworks and libraries (React, Node.js as part of the curriculum).

Designed and implemented responsive, mobile-first user interfaces.

Applied Git / GitHub for version control, collaboration, and project management.

Completed hands-on projects: building dynamic and interactive websites.

Acquired fundamentals of SEO and web accessibility best practices.

Set up development environments and deployed web applications.

Worked independently with mentor guidance, applying project-based methodology.
PHP Node.js Python API containerization-and-virtualization
N/A
INDEPENDENT CHEF
HOSPITALITY
January 2019 - January 2021 (2 years)
Paris, France
Designed and prepared custom menus for private events, corporate functions, and special occasions.

Managed all aspects of kitchen operations, including ingredient sourcing, food preparation, and plating.

Ensured high standards of hygiene, food safety, and quality control.

Delivered exceptional customer service, adapting dishes to client preferences and dietary requirements.

Planned and executed events from concept to completion, managing budgets and timelines effectively.

Developed signature dishes and experimented with innovative culinary techniques.

Collaborated with clients to create memorable gastronomic experiences and maintain strong client relationships.