Nobody dares touch it
The application runs, but every change is frightening. The people who wrote it have left, and the documentation left with them.
Take back control of an application that is becoming obsolete or starting to get away from you
We combine the power of AI with the rigour of our engineering to make your existing web applications reliable, secure and scalable, step by step, with no big bang and without stopping your business.
Case study
A critical application modernised with no service interruption
A remote payment solution used at scale, modernised step by step while it kept running.
Process ID
From a proven application to a modular, secure web application
Interface rethought from mobile to desktop, code partitioned feature by feature, security and permissions centralised in a single entry point. All of it with no big bang and no service interruption, on an application where every payment counts.
every day, thousands of remote payments sent and secured
What the modernisation changed
- A completely rethought merchant interface, unified from mobile to desktop
- Modular code partitioned feature by feature, simpler to maintain
- Security, permissions and validation centralised in a single entry point
- Robust bulk processing, fair between merchants
- Business data flowing through a single validated, documented path
“The needs kept growing, and then the security questions arrived. We knew we could lean on GDN at any moment.”
“Thanks to GDN, we are credible in what we do. When we say there is a project, it will get done, and it will be done well.”
“A provider we trust completely, who we can lean on, who we can talk things through with calmly, and who we can move forward with.”
“Other companies have approached us about our website. I would rather stay with GDN: we have worked together for a long time and I know who I am moving forward with.”
“We know we can lean on GDN, and that things can move quickly.”
“For me, it is a real comfort: I know it will be done well.”
“I recommend GDN to any company that wants to sell online.”
“With GDN, we know the quality is there, and the follow-up too.”
During a major datacenter incident:
“It is thanks to the work and the safeguards put in place beforehand that we were able to bring both sites, Francofa and Cordia, back up very quickly.”
“On maintenance, security, web services… GDN knows exactly where to look.”
“On security, we can call on GDN. The team has an expertise that makes us confident it knows what it is doing.”
This is for you if
Security has become a subject
Unmaintained versions, ageing dependencies, patches falling behind. A client audit or an incident has put it back on the table.
Every change costs too much
What used to take two days now takes ten. Technical debt has piled up and is now slowing your business down.
How we work
No big bang, and you stay in control of your code
We start from your reality (the stack, the usage, the debt) and move forward in steps. Your tool stays online while the work happens, and you sign off on each stage before the next one starts.
No big bang
Security
Technical debt
AI-assisted development
Human in the loop
No lock-in
Get my application audited
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01
Understand what exists
Application audit, mapping of usage, technical debt and security risks. We know what we are touching before we touch it.
“Copy, photos, approvals: this redesign asked very little work of me.”
President, MCB “A very well run engagement and constructive exchanges: we were able to adjust the new site as it was being built.”
President, MCB “Exchanges at the right pace and good visibility on progress: it was very good.”
President, MCB “GDN is the one that proposed this platform to us, every step, every flow. A platform from A to Z.”
Digital Project Manager, Francofa-Eurodis (Rexel Group) -
02
Prioritise the work
What is urgent, what is important, what can wait. Trade-offs decided together and aligned with your budget.
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03
Modernise in stages
Version upgrades, targeted refactoring, automated tests, hardening. Your tool stays online while the work happens.
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04
Make it last
Pragmatic AI integration, living documentation, source code delivered continuously. We keep pace with your business.
The power of AI, in a controlled frame
Our developers work with AI coding agents: that is what makes us fast. The frame around them is what spares you the throwaway code those tools produce when nobody is watching them.
AI-assisted development
Supervised code generation, AI-assisted code reviews and documentation, gradual automation of development. We move in small cycles, never in big leaps.
Systematic human control
Human in the loop: nothing ships to production because an AI wrote it. A senior developer decides, reviews and owns every release.
Automatic guardrails
Automated tests, static analysis, CI/CD, version and release management. Whatever slips through too fast is caught by the machine before it reaches you.
Development rules
Memory banks: documented context for the AI
Small cycles
Assisted code reviews
Automated tests
Static analysis & PHPStan
CI/CD
Versions & releases
You end up with an application people dare to change
The goal is not to rewrite everything. It is to make your application safe, understandable and able to evolve again.
★ The flagship asset
An audit that says what to do, and in what order
Not a hundred-page report, but a readable map of your stack, your risks and your debt, with the work ranked by urgency and costed. Usable even if you then decide to proceed without us.
first findings within a few days
Then, stage after stage
- Version upgrades and dependencies brought up to date
- Vulnerabilities fixed and security verified
- Automated tests on the critical paths
- Business and technical documentation finally up to date
- Source code delivered continuously, with no lock-in
Cybersecurity
CyberVadis Platinum medal, 984/1000, Mature level
An objective proof of cybersecurity maturity for your applications, B2B platforms and business-critical digital tools.
What sets us apart
Beyond development, we make sure the project stays solid, easy to evolve and under your control.
CyberVadis Platinum Medal · 984/1000 Contact our experts-
01
You stay in control of your tools
Source code and documentation delivered continuously, with nothing held back and no lock-in. Your teams can take over what we build.
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02
AI development on solid foundations
Our developers work with AI coding agents, under human review and within a structured engineering framework: CI/CD, tests, development standards and documentation.
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03
Security at the core
984 out of 1000 in the CyberVadis assessment. On projects: code and dependency analysis at every delivery, automated OWASP tests and OpenVAS scans.
See the details of the CyberVadis assessment → -
04
A team that builds on your business knowledge
A dedicated team, trained on your application and your ecosystem, that learns your context as the project progresses and records it in maintained documentation.
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05
Your tools stay easy to evolve
A clear architecture, development standards and maintained documentation, so your application can evolve without starting from scratch with every new requirement.
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06
Continuous accountability
Scoping, build, production, maintenance, evolutions and modernisation: GDN stays engaged over the long term, with no break in accountability and a one-year warranty included.
Case studies
They trusted us with their projects
Francofa-Eurodis (Rexel Group)B2B distribution / e-commerce
Application for digitizing B2B client registrations
8,000+registration files processed See the case study
Hightekers GroupFreelancing with all the benefits of employment
Managing an entire consultant network, from secure onboarding to payroll
4,000+independent consultants supported, from registration to payroll See the case study
Francofa-Eurodis (Rexel Group)B2B distribution / e-commerce
B2B e-commerce platform and client self-service, backed by the ERP
30,000+products orderable online, at each client's negotiated price See the case study
OFIMMulti-agency real estate, internationally
A single back office with built-in CRM to run a multi-agency real estate network
From data entry to sales follow-upa single tool for the daily work of the network's agencies and sales agents See the case study
Process IDB2B web application publishing
Modernizing a critical payment application, without interruption
Every daythousands of remote payments sent and secured See the case study
Cordia (Rexel Group)Fire safety / E-commerce
B2B e-commerce platform and client workspace, backed by the ERP
10,000+professional accounts served, each at their negotiated price See the case study
AnnealsysB2B - Semiconductor equipment
A bespoke website, from technical catalog to lead generation
Every machinepresented with its applications, specifications and documentation, in the visitor's own language See the case study
OFIMMulti-agency real estate, internationally
A real estate platform, from public site to automated listings
20 agencieson one digital foundation: Reunion, Mauritius, Madagascar See the case study
Cordia (Rexel Group)Fire safety / E-commerce
Continuously internationalizing a B2B e-commerce site
2,000+references created then kept up to date in English automatically See the case study
ALMASelf-propelled grape harvesters
Filtering spare parts by machine serial number
30+ countriesa worldwide fleet filtered by serial number See the case study
Francofa-Eurodis (Rexel Group)B2B distribution / e-commerce
Upgrading a heavily customized platform from PrestaShop 1.6 to 9+
From 1.6 to 9+the PrestaShop path completed without losing a single business customization See the case study
Hightekers GroupFreelancing with all the benefits of employment
Complete travel expense management tool
Several thousand tripschecked and reimbursed, from entry to payment See the case study
Hightekers GroupFreelancing with all the benefits of employment
Modernizing the legacy system toward an API-First architecture
150API endpoints delivered progressively, without disruption See the case study
MCBParts & accessories for concrete batching plants
Turning an end-of-life B2B e-commerce platform into a modern, secure store
Zero re-entrycatalog and customer accounts fully migrated See the case study
Hightekers GroupFreelancing with all the benefits of employment
Integrating two-factor authentication (2FA) via a mobile app
Thousands of accountsprotected by a second factor, with no dependency on SMS or email See the case study
Francofa-Eurodis (Rexel Group)B2B distribution / e-commerce
Adjustable multi-factor authentication
Every loginto the back office protected by a second factor See the case study
Cordia (Rexel Group)Fire safety / E-commerce
Self-service B2B media library module
The entire catalogin HD visuals and documents, self-service See the case study
AmmonitiaRental management & wealth advisory
Modernizing the Investors Department's business application
3 unitsbrought together in a single repository See the case study
CT49Vehicle inspection centers
Online vehicle inspection booking platform, multi-center and multi-actor
24/7self-service online booking, with no phone call needed See the case study
Let us start by looking
A short audit is enough to know whether your application deserves to be modernised, rewritten, or simply left alone a while longer.
Get my application audited