Boost your legacy
accelerate now

Your existing software may feel sluggish, clunky and unreliable โ€” but it doesnโ€™t have to stay that way. At Spartner we dust off the cobwebs, rebuild the core with smart AI tools and expand it modularly. The result is a modern, stable application that matches your ambitions without the long radio silence of a traditional rebuild.

Old code, new opportunities

Why wait?

Every month of delay costs speed, customers and euros.

Automate

We leverage generative AI to speed up 80โ€“90% of repetitive coding. Fewer human errors, more focus on unique logic.

Integrate

We connect new microservices safely to your existing core, keeping operations running while we modernise โ€” stress-free for your team.

Scale

Ready for growth? Our cloud-native architecture doubles capacity at the press of a button. No more hardware pains, just happier end-users.

Validate

We prove the business case up-front with hard numbers: performance metrics, TCO calculations, ROI scenarios. You know exactly what youโ€™re getting into.

Why smart renovation works.

A modern foundation without breaking the culture
Why smart renovation works

Why smart renovation works.

Picture your software as a characteristic canal house. Charming, yet the wiring dates back to 1978 and the crawl space is damp. Do you demolish it? Or do you renovate cleverly, floor by floor, while the occupants keep sleeping?

Continuity first

  • Spartner builds a digital twin alongside your current production environment.

  • Users only switch over once every vital feature has been validated one-to-one.

AI as a turbo-charger

  • Our internal models analyse legacy codebases and generate clean, tested modules.

  • Notably, teams report 30โ€“40% fewer regression bugs as a result.

Business case over gut feeling

  • Together we calculate savings on licences, hardware and support.

  • Whatโ€™s more, we simulate new revenue streams as soon as the API layer opens up.

Key benefits at a glance:

  • faster release cycles (weeks, not quarters)

  • measurably less downtime

  • easy integration with BI, IoT and mobile apps

  • lower operational costs through cloud elasticity

  • future-proof architecture with microservices and event streaming

How do you navigate this modernisation journey?.

A step-by-step approach that delivers impact without disruption.

Step 1: System snapshot

Step 1: System snapshot.

We begin with a read-only copy of production. Tests run in parallel, users notice nothing and we instantly see the real bottlenecks โ€” no assumptions.

Step 2: Functional digital twin

Step 2: Functional digital twin.

AI agents reverse-engineer processes and convert them into a Universal Application Model. This lets developers understand the โ€œintentโ€ behind the code, not just the syntax.

Step 3: Modular rebuild

Step 3: Modular rebuild.

Domain by domain we create microservices: auth, orders, reporting. Each service gets its own tests, CI pipeline and versioning scheme.

Sub-step: Shadow traffic โ€” live traffic flows to both old and new, so we can compare in real time.

Step 4: Accelerated UI refresh

Step 4: Accelerated UI refresh.

We derive the design system from the current front-end, refresh it in React or Flutter and auto-generate wherever possible.

Step 5: Phased cut-over

Step 5: Phased cut-over.

When metrics (latency, error ratio, throughput) outperform the legacy system we flip the feature flags. No big bang, plenty of relief.

Step 6: Optimise and innovate

Step 6: Optimise and innovate.

After migration we expand: reporting dashboards, machine-learning recommendations, no-code workflow designers โ€” whatever the business needs.

Ready to give your software wings again?

Ready to give your software wings again?

Schedule a coffee call with one of our modernisation architects. Weโ€™ll listen to your story, share honest insights and explore whether our AI-driven approach fits. No sales pitch, just a clear plan.

Practical tips for quick wins

Practical tips for quick wins.

Small tweaks, big impact

In practice organisations often stall on a single bottleneck, not the entire system. So tackle that one pain point first.

Reduce chatty databases

  • Cache read-intensive queries with Redis.

  • Bundle writes in an event queue to absorb spikes.

Automate tests

Use contract testing (for example Pact) between old and new services. That way you spot breaks before the deploy.

Measure everything

Install a lightweight observability suite: OpenTelemetry, Prometheus, Grafana. Because without numbers, performance is just a gut feeling.

A critical look at pitfalls

A critical look at pitfalls.

Modernisation is not a silver bullet

Not every application lends itself to an AI-driven rebuild. A monolith with thousands of undocumented stored procedures can delay your project by months if youโ€™re not careful.

Overly ambitious scope creep

Donโ€™t hang all your digital dreams on modernisation. Keep releases small and incremental.

Insufficient business alignment

As mentioned earlier: without buy-in from finance and operations, the roadmap will stall โ€” no matter how good the code is.

Forgotten licences

Sometimes you keep paying for old runtime licences for years. Check contracts early to avoid double costs.

Looking ahead โ€” AI as a colleague

Looking ahead โ€” AI as a colleague.

From code generator to code caretaker

AI models are already better at refactoring than the average developer on a Monday morning. Within two years, experts expect autonomous code maintenance to handle 50% of all simple bug fixes.

Continuous regeneration

Code ages. AI agents that refactor daily keep your stack fresh โ€” as if a cleaning crew sweeps through every night.

Explainable migrations

New tooling not only generates code, but also migration documentation in plain English. Handy for audits.

Ethics and governance

Letโ€™s be clear: bias in code suggestions is a real risk. Strict review flows and model audits remain essential.

Hans Lugtenberg

"A deal is a deal"

Yield.inc is a new asset manager in the Netherlands that focuses on excellent customer experience, sustainability and technology. When faced with the question of whether to develop our platform in-house or with a partner, we got in touch with Spartner. We are still 100% behind the choice for Spartner because we own the source code and with Spartner, a deal really is a deal, whether it concerns the delivery date or the agreed budget!

Hans Lugtenberg Partner at Yield Inc.

Norbert Wegter

"A professional software partner since 2010"

Spartner is involved and contributes in our search for innovations and always delivers top-notch work. After the first Huurda.nl version got out-dated, we collaboratively launched a completely new version in 2020.

Read more

Norbert Wegter Owner of 123wonen and Expat Homes Holland

"Doijer & Kalff"

After transferring our D&K portal to Spartner, we have elevated the further development and continuity to a higher level. Although the D&K platform was originally developed internally, our technical expert can now focus on other innovations within Doijer & Kalff. Spartner provides the quality we need without excessive costs. They have seamlessly taken over the care of our portal, allowing us to benefit from a flexible capacity that perfectly aligns with our future plans and innovation goals.

Reinier van Bergen Managing Director at Doijer & Kalff

Jurjen Terpstra

"Pragmatic and flexible collaboration"

Spartner has created a customized portal for us for the accountability of large-scale collaborative projects. This enables us and our partners to execute and account for their plans in a shared environment that is secure, transparent, and manageable. The pragmatic and flexible collaboration with Spartner has ensured that we have quickly achieved a functional and user-friendly environment.

Jurjen Terpstra Managing Partner at Wecreate Consulting

Marco Caspers

"AI and machine learning as legal tools"

In 2020, we transferred the development of Lynn to Spartner. As a result of their fast development process, the Lynn platform achieves an increasingly central role in the legal world.

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Marco Caspers Software Development Manager at Lynn Legal

Bjorn Gubbels

"As a business you must dare to move forward"

Innovation and change are not always welcomed with equal enthusiasm by our employees, man is a creature of habit but as a company you have to dare to move forward and the need for a contemporary drawing program for the realization of various constructions with our Masterbloc bricks was high. For us but also for Spartner, this challenge was a bit of pioneering and together we had to overcome some hurdles to arrive at a beautiful and efficient business tool. A development and learning process for both parties, in which the feedback of questions and desired adjustments by our employees to Spartner was always in good consultation and we could count on quick feedback and targeted solutions. We continue to exchange experiences with Spartner and look back and forward to a successful collaboration.

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Bjorn Gubbels Owner of Masterbloc

Marco Leenders

"Spartner extends our capabilities and development capacity"

With weekly calls, using our Azure DevOps sprint system, Spartner actively works together with our innovation, communication and software development departments.

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Marco Leenders Head of Automation

Gemeente Groningen

"Flexible collaboration with yearly updates"

The projectteam of the city of Groningen is very enthusiastic about the "Roomfinder" platform.

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Gemeente Groningen Projectteam

Josh Mountain

"Have been using Laravel Excel for years"

We requested custom help to a performance challenge we had in our implementation of Laravel Excel. I was amazed how quickly these Laravel artisans achieved significant performance gains, which saved us a lot of development time.

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Josh Mountain Co-Founder at IncentivePilot.com

Maurice Evers

"Higher occupancy rate thanks to our user-friendly platform"

Throughout the great years that we cooperate with Spartner (previously Maatwebsite, Ed.), our software has been developed continuously. Students and landlords actively work with features like allocation, payments, chat, contract generation and more.

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Maurice Evers Head of Student Housing Department

Maarten Bremer

"Innovating in the digital identification network of The Netherlands and Europe"

The pro-active approach of Spartner was crucial in understanding the complexity of the eHerkenning network.

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Maarten Bremer CTO / Founder Ensured

Niels Winters

"Innovation in legal technology"

As jurists with knowledge of IT, we highly value quality; within code, but also in process. The high work-level and trustworthiness of Spartner gives us the capacity to continuously create innovative features.

Read more

Niels Winters Managing Director JuriBlox

Frequently asked questions

Straightforward answers to the questions we hear most often.

Do I have to shut down my current system during modernisation? ๐Ÿ˜Š

No. Thanks to our shadow migration everything keeps running. Users will only notice faster load times once we go live.

Does AI really work for every programming language? ๐Ÿค”

AI agents perform best on popular languages (C#, Java, PHP, JavaScript). For exotic languages we combine AI with manual refactoring.

What about security in microservices? ๐Ÿ”

We follow zero-trust principles, token-based auth and encrypted service-to-service communication. We also run automated pen tests.

Can I keep parts of my monolith? ๐Ÿ—๏ธ

Yes. We decouple step by step. Certain stable modules can remain for the time being as long as they meet performance and security requirements.

How quickly will I see ROI? ๐Ÿ’ถ

On average within 12โ€“18 months thanks to lower maintenance costs and higher productivity โ€” but we calculate the exact figures in your business case.

What happens to my data during migration? ๐Ÿ› ๏ธ

We run migration scripts in parallel, execute checksums and have end-users confirm test scenarios. No data loss, complete peace of mind.

Will my team become redundant? ๐Ÿ˜…

Certainly not. AI handles the boring work; your developers focus on innovation and customer-specific logic.

Does this approach suit regulated industries? ๐Ÿ“œ

Absolutely. Our tooling produces complete audit trails and we operate in line with ISO 27001 and GDPR guidelines.

Feel like a cup of coffee?

Whether you have a new idea or an existing system that needs attention?

We are happy to have a conversation with you.

Call, email, or message us on WhatsApp.

Bart Schreurs
Business Development Manager
Bart Schreurs

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