What is custom business software?
Custom business software is an application developed specifically for your company’s processes, rules, and users, as opposed to a standard SaaS solution that suits 80% of companies in your industry.
Your current software—CRM, ERP, or management tool—meets 80% of your needs. The remaining 20% are exactly what make the difference: your business rules, your internal processes, and the way you work. No off-the-shelf SaaS solution understands these. You adapt to the tool, working around its limitations with Excel exports, manual processes, and third-party tools that are connected as best as possible.
For 30 years, custom software development was reserved for large companies for economic reasons: it was simply too expensive. AI has changed everything. It eliminates the mechanical aspects of development and makes custom software accessible to small and medium-sized businesses. This is what IT Systèmes has standardized under the name“hyperdevelopment.”
Industry-specific software designed for your sector
Chartered accountant
Lawyers / Legal
Architect
Industry
Local Governments and the Public Sector
Service and consulting firms
Why Custom Software Can Transform Your Business
Custom software isn't just a productivity tool. It becomes the digital backbone of your business. Whereas standard SaaS forces you to adapt your processes to the tool, custom software flips that logic on its head: the tool adapts to the way you work.
In practical terms, deploying custom software means:
- Your business processes are followed 100% of the time instead of 80%, without having to resort to workarounds in Excel or third-party tools
- Elimination of recurring SaaS subscriptions in favor of a one-time, amortizable cost
- Complete independence from software vendors: the source code belongs to you
- Evolution driven by your business needs, not by a vendor’s roadmap
For 30 years, this approach was reserved for large companies. Generative AI and rapid development are changing the game: what used to take a team three months to complete can now be done in just a few days, under the supervision of senior experts. These productivity gains are fully reflected in our pricing.


Why Choose IT Systèmes for Your Business Software
- Software Developer and Integrator: We don’t just develop your software. We integrate it with your existing IT systems (ERP, CRM, EDM, M365, Active Directory) so that it fits seamlessly into your daily operations.
- AI-powered hyperdevelopment: Our team uses generative AI to accelerate code generation, testing, and documentation. The result: development times reduced by a factor of 3 to 5 compared to traditional development.
- Agile methodology with short sprints: incremental deliveries every 2–3 weeks. You test, you validate, we adjust. No six-month-long blind spots.
- Robust, cloud-native architecture: microservices, containers, REST APIs, DevSecOps. Your software is scalable, secure, and portable.
- Security and compliance by design: GDPR, ISO 27001, NIS2. Encryption, strong authentication, security audits at the end of each sprint.
- Maintenance and Long-Term Development (TMA): Your software grows and evolves alongside your business. Bug fixes, updates, new features, and responsive support.
Hyperdevelopment, our signature method
After two years of R&D, IT Systèmes has brought a methodological breakthrough to market. AI does not replace our developers; it eliminates the routine aspects of their work.
Our teams now focus on domain expertise and architecture, while specialized AI agents generate the code, tests, and documentation. In practice, a project that used to take a team three months to complete is now finished in just a few days, under the supervision of senior experts. These productivity gains are fully reflected in our pricing: our clients now receive custom ERP solutions at a cost 5 to 7 times lower than the quotes they received a few years ago.
“We’ll be able to develop solutions 30 times faster and make these business tools accessible to as many people as possible.”
Samir Amara, CEO of IT Systèmes — LES ÉCHOS


Standard SaaS or custom software?
Six structural differences that can help you make the right choice based on your situation.
- Adaptation to your processes: 80% with standard SaaS, 100% with custom software tailored to your company’s unique needs.
- Ownership of the code: With SaaS, you’re renting. With custom development, you own 100% of the source code.
- User cost: SaaS billed per seat on a monthly, tiered basis. Custom plan: unlimited users, one-time payment.
- Functional evolution: With SaaS, you’re at the mercy of the vendor’s roadmap. With a custom solution, you drive it based on your business needs.
- Hosting and data: SaaS solutions are often hosted outside the EU. Custom solutions: hosting in France, native GDPR compliance.
- Total cost over 5 years: increases with the number of users for SaaS. Stable and amortizable for custom solutions.
For more information, see our article “ Business Software: Definition, Benefits, and Custom Development ."
They canceled their SaaS subscription
Obeevi, an independent audiovisual production company, had been searching for years for a tool capable of adapting to its highly specific production processes. No off-the-shelf solution met their needs. In just 22 days, IT Systèmes delivered a unified CRM and project management tool, custom-designed for their workflows.
“Our business is unique, and our processes are what set us apart. We now have the tool that allows us to digitize our expertise.”
Styde Jacquin — Co-CEO, Obeevi

OUR INTRODUCTORY OFFER
Try the software before you pay.
You only pay once you’re satisfied. No commitment, no risk. Our teams will build a Version 0 of your custom software based on your requirements. If you approve it, we’ll scale up production. If not, you won’t pay a thing.
Offer subject to eligibility — formalized use cases or specifications required.
Are you looking to automate a business process using AI? Start with a free AI agent audit →
STEP 01
Have you already identified your needs?
A requirements document? Business use cases? Perfect. We’ll use your work as a starting point to define the scope of Version 0 with you during a 30-minute discussion.
STEP 02
We're building your V0
Within 5 to 10 days, a working version of your software, based on your use cases. Your real data, your business terminology, your workflows.
STEP 03
Convinced? Let's wrap this up.
Not convinced? You don't pay a thing. You can keep the V0 version as a demo, with no obligation and no hidden charges.
Quick Audit
ROI Calculation
Working prototype (not a set of specifications)
Development in 2-week sprints
Deployment and Continuous Improvement
FAQ: Custom Business Software
What is the difference between custom business software and standard SaaS?
Standard SaaS solutions (Salesforce, Sage, Monday, etc.) address general-purpose needs. Custom business software is designed specifically for YOUR processes, YOUR management rules, and YOUR users. You don’t have to adapt your business to the tool—the tool adapts to you. And you own it.
How long does it take to develop business software?
With our AI-powered Agile methodology, a simple application can be delivered in 6 to 8 weeks. A full-featured software solution with integrations (ERP, CRM, EDM) takes 3 to 5 months. Thanks to short sprints, you’ll have usable versions as early as the first few weeks.
How much does custom business software cost?
Our packages are transparent and all-inclusive. Small-scale solution (replacing Excel, Access, or small software applications): under €10,000, under 10 days. Custom CRM (replacing Salesforce, HubSpot, or Dynamics): under €50,000, under 50 days. ERP / Core Business (replacing Odoo, SAP, Cegid): less than €100,000, less than 100 days. All packages include: unlimited users, code ownership, free migration, hosting in France. No commitment, no per-user cost. Ongoing maintenance (TMA) represents 15–20% of the initial cost per year.
What technologies do you use?
Backend: Java, Python, C#, PHP. Frontend: ReactJS, NextJS, VueJS. Databases: SQL Server, PostgreSQL, MongoDB. Cloud: Azure, AWS. Integration: REST APIs, GraphQL. Security: DevSecOps, Azure AD, MFA, TLS encryption. We choose the best combination based on your specific needs, without locking you into a single technology.
How does AI accelerate development?
Our team uses generative AI at every stage: generating boilerplate code, writing unit tests, automating documentation, assisting with code reviews, and creating UX mockups. AI doesn’t replace developers—it boosts their productivity. The result: development times and costs reduced by a factor of 3 to 5 in certain phases.
How do you integrate the software into my existing IT system?
We connect your business software to your existing tools via secure APIs (REST/GraphQL), native connectors (Power Automate, M365), or custom middleware (FlexFlow) for legacy systems without APIs. No overhaul of your IT infrastructure is required.
Is there any financial assistance available for business software?
Yes. There are several programs available for small and medium-sized businesses (SMEs): the research tax credit (CIR) if the project involves innovation, BPI France grants (digital loans), regional digital vouchers, and France Num programs. We can help you identify the grants that are best suited to your project.
What happens after the system goes live?
We offer a third-party application maintenance (TMA) contract that covers: bug fixes, security updates, functional enhancements, and user support. Your software isn’t static—it evolves alongside your business. Our contracts have no minimum term.
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