React & Next.js interfaces
I can turn your designs into responsive pages and reusable components, with attention to keyboard navigation, mobile use and the technical foundations of SEO.
Freelance development for agencies
Your next project.
An extra developer on your team.
I’m Gilles Mastropasqua, a freelance full-stack developer in France. I help agencies turn designs into working websites, build application features and move existing projects forward with Next.js, React, Payload CMS and PHP.
Independent since 2010 · Based in the French Alps
Support where your project needs it.
A defined part of a build or support across the project: we can agree on a scope that fits your team and the work already in place.
Content management & applications
I can connect the interface to Payload CMS, build content structures and develop interactive features or API integrations for the needs of your client’s website or application.
Existing projects & maintenance
I also work on JavaScript and PHP projects that are already running. We can identify the part that needs attention, then plan fixes or new features around the existing codebase.
A clear scope, from brief to handover.
Here is how we can organise the collaboration, whether you need a specific feature or broader development support.
Define the work
We review the brief, designs and existing code, then agree on the deliverables, technical constraints and target schedule before development begins.
Build and review
We agree on review points so your team can check the implementation as it takes shape. Questions and dependencies are discussed alongside the work they affect.
Verify and hand over
The agreed scope includes the checks and handover your team needs: for example, mobile and keyboard checks, project-specific tests, setup notes or deployment support.
Projects behind the services.
A tourism website, an interactive application and a contribution to a shared mapping project. Each case explains the product and my involvement.
Website development
O’Limpide Verdon
An outdoor adventure website for the Verdon, with a custom interface and content managed through Payload CMS.
Read the case study
Application development
EquiGenes
An equine genetics application combining a coat colour calculator with accessible educational content.
Read the case study
Contributor
TET Atlas
A contribution to the interactive mapping application for the Trans Euro Trail.
Read the case studyBefore we work together.
Can you join a project that has already started?
Yes. Share the current stack, the part you need help with and any relevant designs or documentation. We can use that first review to define a suitable scope.
Can you work from our designs?
Yes. I can handle the implementation of your interfaces and connect them to the content or application logic. We agree on responsive behaviour and interactions as part of the brief.
How do we agree on timing and cost?
Send the brief, the current state of the project and your target dates. I can then assess the work and discuss availability, the estimate and the terms of the collaboration with you.
Tell me where you need support.
Send a short brief, the technologies already in place and your target dates. Links to designs or the current website are useful too.