AI designed for your business processes, not the other way around

Castelis takes your AI from prototype to production: business apps, AI agents, and data platforms that actually work at scale. One partner, from strategy to execution.

Talk to an expert

+500 projects delivered

Since 1999, in France and internationally

+5 business sectors

Dev, cyber, cloud, data and UX under one roof

Certified security

ISO 27001:2022, GDPR and CyberVadis Platinum Medal 2025

# They chose our expertise

/ Our Clients

# Our Expertise

/ From concept to production

A single partner to move from use case to a production-ready product with measurable results, controlled compliance and optimised costs.

Custom Development

Websites, business applications, ERP and mobile. Solutions that integrate into your processes and evolve with your business needs.

Cybersecurity

Governance, technical security, detection and response. ISO 27001:2022 certified, GDPR compliant and CyberVadis Platinum 2025 recognised.

Artificial Intelligence

Data pipelines, AI agents and MLOps. From architecture to industrialisation, for use cases with measurable impact on your business.

Cloud Infrastructure

Cloud migration, managed services and optimisation, with 24/7 monitoring, guaranteed SLAs and data hosted in France.

/

Your challenges, our methodologies

Migrate or optimise your Cloud

Reduce costs and gain agility with a cloud infrastructure tailored to your needs.

Learn more

Secure & monitor your IS

Protect your systems, anticipate incidents and stay in control of your IT security.

Learn more

Leverage Data & AI

Transform your data into performance drivers with operational AI solutions.

Learn more

Build or optimise a business application

Tools that adapt to your business processes and evolve with your needs.

Learn more

Build or optimise a website

An online presence that drives traffic, engages your visitors and converts.

Learn more

Successfully navigate e-invoicing reform

Anticipate the legal requirement and implement a compliant solution without business disruption.

Learn more

# OUR APPROACH

/
An integrated approach, from scoping to operations

Castelis is involved throughout the entire lifecycle of your digital projects: design, development, security and optimisation. Every project is scoped, managed and delivered with rigour, by multidisciplinary teams engaged from start to finish.

Deadlines met, budgets controlled
Teams dedicated to your context
A single point of contact from design to operations

Talk to an expert

An integrated approach, from scoping to operations

+500

Projects delivered

Since 1999

/

24/7

Run & SOC

Continuous monitoring

/

≥99,9%

Guaranteed SLA

High availability

/

+5

Business sectors

Multi-industry

/
Dedicated experts at every stage of your project

250 professionals with complementary profiles: developers, cloud architects, cyber experts, data scientists and designers, who share a common commitment: understanding your context before delivering. Each engagement is led by experienced professionals, involved from design through to operations.

Talk to an expert

Dedicated experts at every stage of your project

# PARTNERS

/ An ecosystem to go further, faster

We work with recognised ecosystems to build solid solutions: CMS/DXP, cloud tools, data platforms and collaborative services. These partnerships accelerate your projects, secure integrations and simplify governance. You benefit from proven best practices, modern tools and lasting support to evolve your product.

# They trust us

EP

Eric Pagan

Chief Financial Officer • Groupe Qualiconsult

“ Castelis demonstrated its flexibility, its commitment to projects and its project management expertise. This is what naturally led us to them. ”

Fabrizio Gallina

FG

Fabrizio Gallina

Digital IT Manager • Prévoir

“ What was truly appreciated with the Castelis Dev Team was their level of commitment, their skills, their responsiveness and their mindset. ”

#INSIGHTS

/ Resources

Supervision informatique

Cloud

Équipe Castelis time_grey

11 min

27 Oct 2026

IT Monitoring: Definition, Objectives and Types

What IT monitoring covers, what it is for, its main types and the tools on the market: a guide to structuring monitoring of your information system.

cybersécurité gouvernance SOC

TMA, tierce maintenance applicative

Custom development

Équipe Castelis time_grey

11 min

20 Oct 2026

Application Maintenance Services: Definition, Scope and Software Enhancement

Corrective, preventive, adaptive: what application maintenance services cover, how they differ from software enhancement and how to frame them.

applications métier développement augmenté développement sur mesure

Préparer ses processus métier à la Data et à l'IA

Digital Artificial Intelligence

Équipe Access it time_grey

7 min

24 Sep 2026

Preparing Your Business Processes for Data and AI: Why It All Starts with the Application

AI relies on what it finds. If your processes are fragmented, the results will be too. Here's how to prepare your IS to get value from it.

applications métier Data IA +2

View all articles

CONTACT

Let's talk about your project

Describe your need to us, and our experts will get back to you within 24 hours.

Technical expertise

25+ years of experience, certified with leading technology partners

Proven methodology

500+ projects delivered, 95% client satisfaction, deadlines met

Ongoing support

Responsive maintenance, team training, 24/7 monitoring

Satisfaction rating

4.8/5