Senior Fullstack Software Architect (freelance contract)

Futurmaster; Boulogne-Billancourt; Sur place; EUR 110 700 - 166 050; Plein temps

Résumé du poste

Sunstice is undergoing a major modernization of its applications. We are seeking a Senior Fullstack Software Architect to join our team on a 12-month freelance contract and contribute to key modernization projects.

You will work in an agile environment, drive the migration from a monolithic application to a microservices architecture, and lead the frontend migration from Vanilla JavaScript to React. Strong Java and Spring Boot experience required, along with TDD and CI/CD practices.

Qualifications

• Eight years of professional software development experience or more.
• Experience delivering application modernization, migration, or large-scale refactoring projects.
• Strong expertise in Java and microservices-based architectures.
• Hands-on experience migrating frontend applications from Vanilla JavaScript to React.
• Solid understanding of modern software engineering practices including TDD, CI/CD, and code reviews.
• Experience with application performance optimization and scalable architecture.

Responsabilités

• Analyze and assess existing technical debt and identify opportunities for improvement.
• Refactor and decompose complex modules and drive migration from monolith to microservices.
• Lead frontend migration from Vanilla JS to React and contribute to backend modernization.
• Design and implement deployment pipelines and CI/CD practices.
• Collaborate with developers, architects, and product stakeholders to deliver scalable solutions.
• Participate in all phases of software development from analysis to testing and reviews.

Connaissances

Java

Spring Boot

React

Vanilla JavaScript

Microservices

TDD

CI/CD

Outils

Docker

GitHub

Description du poste

At Sunstice, we are undertaking a major transformation of our applications to improve scalability, maintainability, and overall software quality. As part of this initiative, we are looking for a Senior Fullstack Software Architect to join our team on a 12-month freelance contract (minimum) and contribute to key modernization projects.

About the Role

You will join an agile team working on strategic initiatives focused on reducing technical debt, evolving our software architecture, and modernizing our frontend applications.

As a senior engineer, you will play an active role in technical decision-making while contributing hands‑on throughout the software development lifecycle.

What You Will Do

• Analyze and assess the existing technical debt, identifying opportunities for improvement.
• Refactor and decompose complex application modules.
• Drive the migration from a monolithic application to a microservices architecture.
• Contribute to the migration of the frontend from Vanilla JavaScript to React.
• Design and implement deployment pipelines and continuous integration practices.
• Participate in all phases of software development, including technical analysis, design, implementation, automated testing, code reviews, and continuous improvement.
• Collaborate closely with developers, architects, and product stakeholders to deliver scalable and maintainable solutions.
• Help define technical solutions that address architectural, performance, and business challenges.

Technology Stack

• Backend: Java, Spring Boot
• Frontend: React, Vanilla JavaScript
• Architecture: Microservices
• Development Practices: TDD
• Containerization: Docker
• Version Control: GitHub

Who We Are Looking For

We're looking for an experienced software architect with:

• At least 8 years of professional software development experience.
• Proven experience delivering application modernization, migration, or large-scale refactoring projects.
• Strong expertise in Java and microservices-based architectures.
• Hands‑on experience migrating frontend applications from Vanilla JavaScript to React.
• Solid understanding of modern software engineering practices, including TDD, CI/CD, and code reviews.
• Experience with application performance optimization and software architecture is highly valued.
• The ability to work autonomously while collaborating effectively within cross‑functional teams.
• Strong analytical skills, a pragmatic mindset, and a passion for solving complex technical challenges.