Rebuild your web application without breaking everything
Your application is slow, ageing or blocking your evolutions? We rebuild it on a modern stack, progressively and without service interruption. Audit, migration plan, controlled rewrite.
Request an audit
Give your application a second life
A sluggish application, a technology that is no longer maintained, changes that take longer and longer to ship: at some point, patching is no longer enough and technical debt ends up slowing everything down. A rebuild means reconstructing your application on solid foundations, while keeping what makes its value — your data and your business logic.
We always start with an audit: what is worth keeping, what must be rewritten, the security flaws to fix, and above all in what order. You leave with a costed migration plan, not a promise of a clean slate.
The rebuild happens progressively, module by module, without cutting the service: your users keep working while the application modernises in the background. This is the so-called "strangler" approach, and we explain the choice between a full rewrite and progressive modernisation on our blog — the latter is almost always safer.
On the technical side, we rebuild on a modern, durable stack: Next.js and React for the interface, Django or Python on the back-end. Enough to last several years without piling up new debt.
If your code doesn't need a rebuild but simply needs to be taken over and maintained, that's a different service: see our code takeover. A rebuild changes the stack and the architecture — not just the maintainer.
Rebuilds adapted to each situation
A startup has a product coded hastily during the MVP phase that no longer handles the load.
The solution provided: progressive rebuild of the back-end towards a scalable stack, data migration and interface overhaul, without stopping growth.
An administration has a business application built on obsolete, unmaintained technology.
The solution provided: audit, migration plan to a modern and accessible stack (WCAG), module-by-module reconstruction with service continuity.
An SME has an old internal software (Access, VB or dated PHP) that hinders its activity.
The solution provided: rebuild into a modern web application (Django/Next.js), migration of existing data and training of teams on the new tool.
A federation has an ageing tool whose vendor has disappeared.
The solution provided: custom reconstruction at feature parity, then experience modernisation, reusing the existing data.
Our standards for every application rebuild.
Security
Reliable architecture, fine-grained access control, GDPR compliance.
Performance
Optimized response times and native scalability.
Simplified Maintenance
Documented code, automated tests, easy updates.
No interruption
Progressive module-by-module migration, service kept running.
Scalability
Modular architecture designed to support your growth.
Transparent communication
A dedicated contact, regular updates, full visibility.
Clear and measurable tracking
Defined milestones, documented deliverables, shared progress.
Ongoing support
Technical support, corrective maintenance and feature evolution.
Concrete custom development achievements
Identify levers to strengthen farm autonomy
An extranet to centralize all information and documentary resources
Offer the most accurate mortgage simulation on the market
Provide tools to master energy consumption
Carry out genomic sequencing projects
Identify levers to strengthen farm autonomy
An extranet to centralize all information and documentary resources
Offer the most accurate mortgage simulation on the market
Provide tools to master energy consumption
Carry out genomic sequencing projects
Identify levers to strengthen farm autonomy
An extranet to centralize all information and documentary resources
Offer the most accurate mortgage simulation on the market
Provide tools to master energy consumption
Carry out genomic sequencing projects
A progressive rebuild, without disruption.
When the technology is no longer supported, when every change is costly and risks breaking everything, or when hiring for that stack becomes impossible. If the application is healthy but simply ageing, a code takeover is often enough: it is mainly the level of technical debt and the state of the architecture that tip the balance towards a rebuild.
We proceed module by module (strangler approach): we replace one part at a time, the old and new versions coexist, and the switch happens progressively. At no point are your users left without a tool.
Yes. Data migration is an integral part of the rebuild: we take over your existing database, clean it up if needed, and guarantee zero loss — backed by automated tests. Your history and references stay intact.
A code takeover keeps the existing code and improves it. A rebuild keeps the idea and the data but changes the stack and architecture. A rewrite starts from scratch. We compare these options in full rewrite or progressive modernisation: a progressive rebuild is the best compromise, real modernisation without the risk of a "big bang" project.
It depends on the scope. An audit with a costed migration plan sits between €5k and €12k. The progressive rebuild starts around €30k–€60k for a mid-size application. It is generally two to three times less risky than a full rewrite carried out in one go.
The audit and scoping take 2 to 4 weeks. The progressive rebuild then spans several months, delivered in regular batches: you see results within the first weeks. An upfront project scoping, backed by a clear requirements document, secures the scope and budget.
What a well-run rebuild brings you.
A progressive rebuild gives you back an application that is fast, secure and pleasant to use, without the trauma of a project that drags on or a risky switch-over.
On a modern stack, changes become simple and fast again: you ship new features in days rather than months, and hiring developers is no longer a headache.
And because we keep your data and your business logic, your teams are not lost: they find their bearings in a tool that is simply more modern and more reliable.
What you gain from a rebuild:
A modern, durable stack, ready for your future changes
Easier maintenance and hiring on mainstream technologies
Ready to get started?
From scoping to prototype, to AI integration.
We support your business software projects from start to finish.