Freelance Java and Spring Boot development
I develop Java and Spring Boot backends within full-stack engagements, fully remote. For Sciences Po, I designed and built an academic portal's foundation in Java 25 and Spring Boot 4 with another developer.
Java backend work for Sciences Po and Suzuki France
One backend foundation I co-designed, and an earlier Java backend I contributed to within the client's team.
Sciences Po · Confidential project
Full-stack foundation of an academic portal
Java 25 and Spring Boot 4 services on Oracle, behind CAS sign-in, designed and built with another developer from the first architecture decisions
National website and dealer-site platform
Contributions to the dealer platform's Java backend within the team, alongside Symfony work and the React back office I built
A service foundation the next team can extend
On the Sciences Po academic portal, I worked on the layer every feature rests on: the Spring Boot service structure, MyBatis on Oracle, CAS authentication, internationalisation and the GitLab CI/CD pipeline. That foundation decides what each later feature costs.
The work ran from architecture to tests, documentation and CI/CD deployment. I can join your backend team and its review process, or take on the Next.js or React interface as well.
For data, I adapt to the layer your codebase already has, whether MyBatis, Spring Data JPA or Hibernate.
Fundamentals
- JVM
- Embedded Tomcat
- Maven
- Gradle
- Dependency injection
- Environment profiles
Possible deliverables
- Spring Boot service foundation with its persistence and configuration layers
- API endpoints, validation rules and documented error handling
- Authentication, for example through CAS
- Internationalisation and continuous integration for the service
- Next.js or React interface consuming the API, for a full-stack engagement
- Engagement
- Team support or project
- Schedule
- Agreed for the engagement
- Indicative rate
- €550 excl. VAT / day (October 2026)
- Collaboration
- Fully remote
- Start date
- To be agreed
A full-stack developer on both sides of the API
Because I also build the interfaces, in Next.js, React or Svelte, I design each backend for the screens that will consume it: clear contracts, readable errors and predictable deployments.
Through jCode, I work with public institutions, established companies and startups. My own products, WorkoutGen and Ragmir, taught me what follows a release.
- of web development
- 10 years
- missions completed on Malt (November 2026)
- 80+
- as a freelancer
- 7 years
- from 47 client ratings on Malt (November 2026)
- 5.0/5
Other areas of expertise
What clients and colleagues say
“I strongly recommend working with JB. He was instrumental in getting our frontend off the ground, handling everything with zeal, unwavering dedication, and unparalleled reliability.”
LinkedIn“Je travaille avec Jean-Baptiste depuis quelques semaines et c'est un réel plaisir. Il s'investit fortement, fournit un travail de qualité, et ce, malgré une situation d'urgence sur le projet. Très bonne communication et à l'écoute. Je ne peux que recommander Jean-Baptiste pour vos projets et travaillerai de nouveau avec lui dès que je le pourrai !”
Malt“Excellent niveau, s'acclimate vite avec son nouvel environnement de travail (compréhension de la stack, des outils de communication, de l'industrie), très autonome et même pro-actif sur la prise de décision. Excellente communication du travail en cours et restant. Se rend facilement disponible. Je recommande pour tout dev d'application web complexe et équipe haut niveau.”MaltLet's talk about your project.
Tell me what you want to build or improve, your budget and your target date.
- Fully remote
- English or French
- France · UK · US
Frequently asked questions
Which Java and Spring Boot versions do you work with?
Java 25 and Spring Boot 4 on my recent work. On your project, I start from the version already running and its upgrade constraints.
How much Java and Spring Boot experience do you have?
One recent project and an earlier team contribution. In 2026, I designed and built the Java 25 and Spring Boot 4 foundation of a Sciences Po portal with another developer; in 2021 and 2022, I contributed to a Java backend within Suzuki France's team.
Can you join an existing backend team?
Yes. At Suzuki France, I contributed to the Symfony backends and a Java backend within the team; at Sciences Po, I built the portal foundation alongside the school's teams. Freelance development for your team sets out how I follow your conventions and review cycle.
Do you also build the interface on top?
Yes. I work with React, Next.js and Svelte, so the interface consuming the API can be part of the same engagement or coordinated with your frontend team.