Get your web application back on track
I audit, take over and maintain existing web applications, AI-generated code included, fully remote. Whether releases have stalled, defects pile up or the original developer has left, I start with a written assessment.
Jean-Baptiste Thery
Senior full-stack TypeScript & AI freelance developer
Agentic developer, within your rules
Available for fully remote freelance
- First step
- Fixed-price audit with an agreed scope
- Next step
- Repairs estimated by work package
- Indicative day rate
- €550 excl. VAT
- Follow-up
- Maintenance scope agreed separately
Understand the problems before choosing the repairs
An application can run locally yet fail in production, ship without a reliable deployment or resist every change. I review it from its code to its operations, then rank what to fix first.
I separate the immediate risks from the work that can wait. You then choose between targeted fixes, gradual modernisation or, where the evidence supports it, a replacement.
What you receive
- A technical assessment with findings ranked by priority
- A review of setup, deployment and maintenance, including the separation between development and production
- Checks of authorisation and database access rules, exposed secrets and dependency vulnerabilities
- A recovery plan with scope and estimates for the proposed work
- Documentation to support future development and handover
From your first message to the handover
The same four steps on every engagement, so you know what happens next and what you receive.
You describe your project
Send a short brief on Malt or LinkedIn: your project, budget and target date. I confirm availability and the next step.
We agree the scope
Scope, schedule, pricing (fixed price or day rate), working hours and how we communicate, agreed in writing before work starts.
You follow the work
Code reviews, demos or written reports keep progress visible. Every change I deliver is reviewed and tested.
Handover and follow-up
Documentation, recommendations and, for development work, code whose rights the contract assigns to you. Maintenance by agreement.
Ask a question on LinkedInApplications I took over, modernised or maintained
Each started from something already in place: a previous version, a platform in production or pages to keep improving.
Version 3 of Sciences Po's mapping tool
Offered to researchers and journalists since 2016, the tool now maps up to millions of rows in the browser, even offline. A complete rewrite designed by the Cartography Lab, which I developed.
National website and dealer-site platform
Two platforms in production, maintained and extended for a year with regular releases, from the national website to every dealer site.
Pages for the Oney+ offering
Five landing pages and information pages built faithfully from Figma, tuned for Core Web Vitals and maintained across two engagements.
What clients and colleagues say
“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“Jean-Baptiste est quelqu'un de passionné qui ne compte pas ses heures et qui se focus sur le résultat final. Il a la tête bien faite, comprends très vite les enjeux, les besoins et assure un delivery rapide et qualitatif. Je ne peux que le recommander.”Malt“Jean-Baptiste a été très réactif et très organisé. Je recommande à 100% ses services.”MaltMaintaining code in production
I was maintaining and extending applications in production years before AI coding tools. I now use them myself, so I know where generated code needs checking.
I start by understanding what works and why, then fix what blocks you, in an order we agree on, without a rewrite you do not need.
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
Areas of expertise
Plan what comes after the audit
Compare the available services on the services overview.
Taking over an existing application
How much does the audit cost?
A fixed price, quoted from the size of the application, the access available and the questions to answer. You receive a written report for your team or another provider, and repairs are then estimated by work package at an indicative €550 excluding VAT per day (October 2026).
Can you review an application built with AI tools?
Yes. I use AI coding tools such as Claude Code and Codex myself, and judge AI-built code like any other, on functionality, maintainability, security and deployment. I check first what such code often gets wrong: access rules, hard-coded secrets, dependencies and the separation between development and production.
Will the application need a complete rewrite?
Not necessarily. A rewrite is one option, not the starting assumption, and the assessment compares it with targeted repairs and gradual replacement, given your dependencies, business constraints and cost. The guide to fixing or rewriting an AI-generated application sets out the signs for each path.
Can you maintain it after the recovery work?
Yes. A maintenance engagement can follow the audit and repairs, covering updates, security fixes and small changes, with its scope, response arrangements and availability agreed before it starts.
Let'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