The 10 best software modernisation agencies in the Netherlands (2026)
How this list came about
For this overview, we reviewed the agencies' own websites and service pages and checked that these are genuine Dutch firms that modernise or rebuild outdated software. We deliberately use neutral, descriptive summaries and no invented scores, so you have an honest starting point for your own orientation. We link to each agency so you can compare them yourself. When reviewing them, we look at:
- Experience with legacy projects previous rebuild or modernisation projects, and for what kinds of organisations
- Approach and risk management how the agency handles the transition, big-bang or phased, and how it limits risk
- Data migration and business logic attention to moving data safely and retaining proven processes
- Integrations experience connecting to existing software, so the new system doesn't stand alone
- Management and ongoing development agreements on what happens after handover
- Knowledge safeguarding documenting how the system works, so you don't become dependent on a single party again
The top 10 software modernisation agencies in the Netherlands
Appfront (Amsterdam)
Custom software, app and integration agency that rebuilds legacy systems as modern web applications
Appfront is an Amsterdam software studio that builds custom software, web applications, mobile apps and integrations, and compiled this overview. When modernising, Appfront rebuilds outdated systems as modern web applications, where possible step by step alongside the existing system so that work carries on. The proven business logic is retained, while the outdated technology makes way for a maintainable foundation. The studio also builds the necessary integrations with your other software.
Get in touch with Appfront →Legacy systems rebuilt step by step as modern web applications, retaining your proven processes, from design through to management.
Prikr (Deventer)
Replacing legacy software step by step while the process keeps running
Prikr from Deventer replaces and modernises legacy software step by step. The agency first maps out the existing system and the hidden business logic, creates a replacement plan, and builds the new system in parallel with the old one. Both systems run side by side for a time, and switchover only happens once a component has proven to work. Suited to organisations that want to renew a business-critical system without work grinding to a halt.
View Prikr →Sqits (Zoetermeer)
Custom software with software rebuilding as a dedicated service
Sqits from Zoetermeer develops custom software and offers software rebuilding as one of its core services. The studio modernises outdated applications into user-friendly web applications and builds the necessary software integrations with existing systems. Sqits focuses on digitising processes and works on web applications, websites, mobile apps and data solutions. Suited to organisations that want to replace their outdated system with a modern, maintainable foundation.
View Sqits →MSML (Deventer)
Rebuilding existing software to the latest standards
MSML from Deventer rebuilds existing software to current standards and gives outdated applications a second life. A common project is converting desktop applications into web-based solutions that are accessible from anywhere, with attention to security and GDPR. The agency also connects legacy systems to modern platforms via APIs. Suited to organisations with an outdated desktop or custom application that is due for renewal.
View MSML →Agencies #5 – #10
#5 EGALiT (Amersfoort)
Low-code rebuildEGALiT from Amersfoort rebuilds legacy applications using modern, cloud-friendly technology on a low-code platform. The agency rewrites the application entirely while retaining the existing functionality and specifications, and works with its own architecture framework for maintainable code. Suited to organisations wanting to renew an outdated system while keeping its proven operation intact.
View EGALiT →#6 Wolfpack (Eindhoven)
Phased rebuildWolfpack from Eindhoven modernises outdated web applications in phases: first securing the data by analysing the existing database and setting up a new data model, then migrating components modularly, and finally phasing out the old system. This avoids a risky big-bang approach. Suited to organisations that want to modernise step by step with minimal downtime.
View Wolfpack →#7 Radorfa (Den Bosch)
Phased migrationRadorfa ICT Group helps organisations analyse, improve and modernise legacy software through a controlled, phased migration to modern platforms. The process covers technical analysis, code restructuring, integration upgrades via APIs and security improvements, while preserving valuable functionality. Suited to organisations with business-critical, legacy applications.
View Radorfa →#8 Bergfort (Woerden)
Custom development and rebuildsBergfort, based in Woerden, develops custom software, web applications and integrations, and rebuilds existing software where that is the wisest route. The agency sees a rebuild as a sound choice once the cost of maintaining and adapting a system exceeds the cost of building anew. Suited to organisations torn between further development and rebuilding who want honest advice on the matter.
View Bergfort →#9 NetRom Software (Utrecht)
Nearshore modernisationNetRom Software, based in Utrecht, provides software development across the full lifecycle, from consultancy and design through to build, testing and management, using a nearshore development model. The agency publishes extensive knowledge on modernising legacy applications and on the order in which to tackle it best. Suited to organisations that want to run a larger modernisation project with a dedicated development team.
View NetRom Software →#10 PAQT (Utrecht)
Existing applicationsPAQT, based in Utrecht, conceives, builds and maintains custom software and AI solutions, from strategy and design through to development, maintenance and management. Alongside new applications, the agency also supports existing ones and acts as a dedicated technology partner from idea to implementation. Suited to organisations seeking a longer-term relationship to renew and manage their software.
View PAQT →All 10 software modernisation agencies at a glance
A direct comparison of the key features. Use this table to quickly see which type of agency best suits your modernisation needs.
| # | Agency | Location | Focus | Suitable for |
|---|---|---|---|---|
| 1 | Appfront | Amsterdam | Rebuilding into modern web applications, step by step | Organisations that want to renew an ageing system without bringing work to a standstill |
| 2 | Prikr | Deventer | Replacing legacy software in stages | Business-critical systems that must not go down |
| 3 | Sqits | Zoetermeer | Custom software and software rebuilds | Organisations that want to replace an old system with a modern foundation |
| 4 | MSML | Deventer | Rebuild, desktop to web | Organisations with an ageing desktop or custom application |
| 5 | EGALiT | Amersfoort | Rebuilding legacy systems with low-code | Organisations that want to renew while preserving functionality |
| 6 | Wolfpack | Eindhoven | Phased rebuilding of web applications | Organisations that want to modernise incrementally |
| 7 | Radorfa | Den Bosch | Phased migration to modern platforms | Organisations with business-critical, legacy software |
| 8 | Bergfort | Woerden | Custom software and rebuilds | Organisations torn between further development and rebuilding |
| 9 | NetRom Software | Utrecht | Modernisation with a nearshore team | Organisations with a larger modernisation project |
| 10 | PAQT | Utrecht | Custom development and existing applications | Organisations seeking a dedicated technology partner |
Big-bang rebuild, phased modernisation or further development: what should you choose, and when?
The main consideration upfront is how you tackle a legacy system. Broadly, there are three routes: rebuild the system in one go and migrate across, replace it gradually alongside the old one, or continue developing on the existing foundation. Which route suits best depends on the state of the technology, how business-critical the system is and how much risk you can carry. The agencies in this overview give you honest input on this.
Choose a big-bang rebuild if…
With a big-bang approach, you rebuild the system in a single project and switch off the old one all at once. This can be the quickest route for a well-defined system, but the cutover happens in one go.
- The system is relatively small and easy to define
- The legacy technology is genuinely unsustainable or insecure
- There are few users, or a quiet moment to make the switch
Modernising step by step if…
With a step-by-step or strangler approach, you build the new system alongside the old one and replace it piece by piece. Both run in parallel for a while, so work carries on and the risk stays small.
- The system is business-critical and cannot go down
- It is too large or complex to replace in one go
- You want to build value and confidence along the way
Continuing to develop the existing system if…
Rebuilding is not always necessary. If the technology is still sound and maintainable, you can build on the existing code and add or improve functionality in a targeted way.
- The codebase is still maintainable and secure
- You mainly need new features or improvements
- The cost of maintenance is lower than that of a rebuild
What should you look for when choosing a software modernisation agency?
Whether you opt for a big-bang rebuild, a step-by-step modernisation or continued development, these signals will help you assess an agency, without passing judgement on any specific company.
Red flags
- No examples of previous rebuild or modernisation projects
- Wants to rebuild everything at once without analysing the old system
- No plan for data migration or for preserving your business logic
- Unclear how risks are limited during the switchover
- No agreements on maintenance and further development after launch
Warning signs
- Only offers a big-bang approach, with no step-by-step alternative
- Little attention paid to integrations with your existing software
- Knowledge of the system is not documented or shared
- Communication is stilted or there is no fixed point of contact
- Only builds, without considering whether a rebuild is actually needed
Green flags
- Analyses the old system and its hidden business logic first
- Gives honest advice on rebuilding, step-by-step renewal or continued development
- Can build the new system alongside the old one so work carries on
- Builds integrations and data migration in as a standard part of the work
- Makes clear agreements on management, security and knowledge retention
Looking for something else?
None of these agencies fit your question exactly, or is your question broader? Then take a look at our other, independent overviews:
- The best custom software agencies in the Netherlands for bespoke software in the broad sense, not specifically for modernising an outdated system.
- The best integration agencies in the Netherlands for those who mainly want to connect existing systems rather than rebuild them.
- The best software companies in the Netherlands for those looking for product companies offering ready-made software rather than bespoke rebuilds.
Conclusion
Modernising outdated software pays off once maintenance becomes too expensive or risky and nobody dares touch the system any more. The key lies in the route: sometimes a big-bang rebuild is the fastest, often replacing it step by step alongside the old system is the safest, and sometimes continued development on the existing foundation is enough. The ten agencies in this overview are genuine Dutch firms that rebuild or modernise outdated software, spread across the country. Use the comparison table and the criteria as a starting point, and speak with a few agencies before you decide.
Want your outdated software modernised?
Appfront is an Amsterdam software agency that rebuilds outdated systems as modern web applications, where possible step by step alongside the existing system so that work can carry on. If you have a legacy system or a specific challenge, we are happy to think along with you. See our page building software or get in touch for a no-obligation conversation.
Frequently asked questions about software modernisation
What this article is and is not. This overview has been compiled by Appfront and lists Dutch agencies that modernise or rebuild outdated software: parties that rebuild or gradually renew legacy systems, outdated Access, Excel or Visual Basic applications and old web apps into modern software. It explicitly does not cover hosting and migration parties that merely relocate existing systems, or pure cloud consultants without their own development. Want to know more about this service right away? Then see our page on modernising old software.
Why Appfront for modernising outdated software
Most parties either move your old system or build something entirely new from scratch. Appfront rebuilds outdated systems into modern web applications, where possible in stages alongside the existing system so that work carries on as normal. Here is what that difference means in practice.
Rebuilding while keeping your proven processes
We start by mapping out the old system and the hidden business logic, then rebuild it on a modern, maintainable foundation. What demonstrably works we keep; the outdated technology that holds you back we let go.
Modernising legacy softwareStep by step, so the work carries on
Where possible, we build the new system alongside the old one and replace it piece by piece. Both run in parallel for a while, so nothing grinds to a halt, and you only switch over once a part has proven it works.
Building softwareFrom design to management, from Amsterdam
Appfront builds custom software, web apps and integrations from Amsterdam. From the first introduction and planning through to development and management, we follow a clear process, and we stay involved after delivery for further development and maintenance.
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