Senior Frontend Developer

Job Title: Senior Frontend Developer
Duration: As soon as possible - 30/12/2025
Location: Namur, Belgium
Language: English, Dutch or French
Work mode : Hybrid

Job Description - Roles and Responsibilities
YOUR ROLE

As part of the continuous optimization of our web platform, we are looking for a Front End Web Expert capable of supporting us in improving code quality , front performance (suggestion for back) , and implementing best practices around modern technologies, particularly real-time (Mercury), REST API and automated tests.

MAIN MISSION:

Supporting a team of developers

Optimisation des performances du front-end (React / Typescript) et du back-end (PHP / Symfony / API Platform)

Optimization of resources used in real time (memory, cpu, first loading),

Implementation of front-end quality standards (nomenclature, error management, etc.)

Redesign of the React/Typescript code architecture and structure, in alignment with modern development best practices

Gradual replacement of legacy code (Bootstrap, JavaScript, old React base)

Implementation of a real Front-End working framework: project conventions, quality standards, modular and scalable organization of the code

Structuring and securing APIs with API Platform

Occasional technical supervision of developers (code reviews, testing, etc.)

Technological monitoring and proposal of continuous improvements on the stack

TECHNICAL ENVIRONMENT:

Back-end : PHP 8+, Symfony 6 (LTS), API Platform, Mercure, MariaDB, Istio, ELK, Azure, NodeJS

Front-end : Typescript, Framework JS (React/mui)

Queuing : Rabbitmq

Testing : Playwright (E2E), PHPUnit, JEST

Database : MariaDB

Cache : Redis

CI/CD : azure devops / Docker / versionning Git/ K8s

Monitoring : APM Kibana, Grafana, PMM, RUM Kibana, Loki, opentelemetry

Migration en cours : React / Typescript / API Platform

RESEARCH PROFILE:

Proven experience as a web integrator

Proven experience in front-end web development, with expertise in React / Symfony / API Platform / Real-time

Very good mastery of real time and related scalability issues

Advanced knowledge of modern front-end in Typescript

Engineering spirit , rigor, sense of optimization

Proficiency in software architecture and application performance

Good communication skills and technical writing

Comfortable with source code management (git, ticketing, etc.)

BONUS APPRECIES:

DevOps experience (Docker, CI/CD)

Front and back end application monitoring

Knowledge of web security (Auth/JWT)

Performance / Validation Tools
Skills:
React Expert Most recent experience: More than 3 years ago
TypeScript Expert Most recent experience: More than 3 years ago
GIT Confirmed Most recent experience: More than 3 years ago
Monitoring Confirmed Most recent experience: More than 3 years ago
Testing Confirmed Most recent experience: More than 3 years ago
Azure DevOps Nice to have Most recent experience: 1 to 3 years ago
PHP Nice to have Most recent experience: 1 to 3 years ago
Symfony Nice to have Most recent experience: 1 to 3 years ago