Custom website development
Castelis designs and develops high-performing, secure websites tailored to your business needs and digital strategy.
Our web expertise
We support our clients in creating custom websites, combining design, performance and technical integration for optimal impact.
Showcase & corporate websites
Showcase your brand, structure your message and generate opportunities with a robust technical architecture.
E-commerce websites
High-performing, secure online stores optimized for conversion, flow management and commercial oversight.
Site factories
A shared architecture for deploying multiple sites with brand consistency, industrialized updates and cost control at scale.
Our services
From creation to maintenance, we support you throughout the entire lifecycle of your website.
Website creation
Design and development of custom websites, aligned with your strategy and performance goals.
Strategic redesign
Modernization of existing websites to improve user experience, performance and SEO.
Maintenance & upgrades
Continuous support to ensure security, performance and functional improvements as your needs evolve.
/ Our project approach
Each project is handled with a clear methodology, from needs analysis to production launch, to ensure an effective and durable website.
Needs analysis
Identification of objectives, users and constraints to lay the groundwork for the project.
UX/UI design
Development of mockups and user journeys for an intuitive and ergonomic website.
Technical development
Custom front-end and back-end integration, respecting performance and security standards.
Testing and validation
Full quality control, functional testing and adjustments before going live.
Go live
Site deployment, hosting configuration and post-launch monitoring.
/ Tech stack
We use modern and proven technologies to develop high-performing, secure and scalable websites, perfectly tailored to your business needs.
Custom stack based on your technical and business constraints.
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Our quality commitments
We design reliable, high-performing and scalable websites. Each project meets rigorous technical standards to ensure security, speed and long-term durability.
All our sites are responsive, performance-optimized and developed according to security best practices. They integrate with your IS to ensure data consistency and process fluidity.
/ They strengthened their digital presence with Castelis
Discover how our clients improved their visibility, image and web performance through tailored projects.
Groupe Leclerc | Security and performance of the e-commerce website
Unification of e-commerce and marketplace sales on a geo-redundant cloud platform.
Apave | Rationalizing and optimizing a vast digital ecosystem
Deployment of a centralized digital platform to harmonize Apave's web presence across 45 countries.
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FAQs — web development
The timeline depends on the complexity and features of the project. A simple showcase site can be delivered in a few weeks, while a complex site may take several months, including design, development and testing phases.
Yes, all our websites meet current security standards, with data protection, regular updates and post-launch monitoring to prevent any incident.
Absolutely. We deliver an intuitive back-office tailored to your website and train your teams so they can manage content independently.
Yes, we develop integrated websites capable of communicating with your ERP, CRM or any other system to automate your processes and centralize your data.