Freelancer profile translated to English.

Description

Design engineer specializing in the PHP / Symfony ecosystem, I work on critical issues: refactoring legacy code ("spaghetti") and optimizing applications with high data load.

My background combines solid rigorous training (Master's in Computer Science & Bachelor's in Mathematics-Statistics) and proven field experience, particularly in the maintenance and scaling of a major community platform (database of over 13 GB in production, optimized in native PHP to ensure immediate response time without a framework).

Strategic Intervention Areas:

**Refactoring & Clean Code**: Audit, securing legacy code through unit tests (PHPUnit), isolating flows via decoupled architectures (CQRS, DTO, Managers), and progressive migration to Symfony 7.4+ / PHP 8.3.
**High Performance Backend**: Optimization of complex SQL queries, implementation of high-performance caching strategies (Redis), and real-time event management (Mercure).
**Complex Integrations**: Connection of critical third-party APIs (Stripe, PayPal, Avis Vérifiés, France Travail, ...).

**Work Method**:

I favor a culture of delivery and transparent asynchronous communication (concrete functional demos). No meeting-mania or time-consuming daily meetings: my goal is to deliver documented, tested, and scalable code.

Available for technical reinforcement or backend architecture missions.

Industry field of expertise

Languages

French
Native or bilingual
English
Fluent
Spanish
Basic

Workplace preferences

Remote only

Primarily works remotely

Breizh Digital
PHP / Symfony Developer Engineer — Design & Backend Modernization
DIGITAL AND IT
July 2020 - June 2025 (4 years and 11 months)
Vannes, France
Refactoring and evolution of complex web applications under PHP 8 / Symfony architecture.
Securing deployments and implementing decoupled architectures (DTO, Services) to simplify long-term maintenance.
Integration of national and international scope API ecosystems (Payments, public services, logistics).
Symfony PHP twig MySQL Git
-
Backend & Performance Architect — High Availability Community Platform
VIDEO GAMES AND ANIMATION
October 2017 - May 2019 (1 year and 7 months)
Technical lead for the optimization, stability, and scaling of a high-traffic web application, used daily by a large community.

Key Achievements:
**Mastery of large-scale data**: Management and optimization of a production database exceeding 13 GB.
**Raw performance without framework**: Development of complex features and data flow processing in pure PHP, ensuring minimal response time and zero system slowdowns under heavy load.
**Architecture modernization**: Implementation of the CQRS pattern to isolate data reads and writes, ensuring long-term scalability.
**High availability**: Continuous optimization of back-end code to handle real-time traffic peaks without service interruption.
Database Management Algorithms PHP Legacy Software Architecture

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Master's Degree, Computer Science
University of South Brittany
2020
Master, Informatique
Bachelor's Degree, Mathematics, Computer Science and Statistics
University of South Brittany
2018
Licence, Mathématiques, Informatiques et Statistiques

Guillaume V.

PHP / Symfony Developer Architect — Refactoring

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