Modernisation of
legacy systems

We build and modernise large-scale systems, such as ERP and PIM solutions – tailored for efficiency with no disruptions to daily business operations.

Business-critical systems are the cornerstone of a digital strategy: they have a direct impact on the efficiency of daily operations, competitiveness, and information security.

Taiste staff member together with Hesburger staff

Six approaches to system modernisation

Modernising a system does not always mean a complete overhaul. There are several ways to develop or replace the current solution – from light interface solutions to a full rebuild. Below are six of the most common approaches, which we can combine case by case according to your organisation’s needs, budget, and technical situation.

Improve the existing system

Encapsulate

Modern API interfaces are added to the existing system, enabling the deployment of new functions and integrations without major changes to the system’s internal structure.

This approach is particularly suitable for stable, business-critical systems whose lifecycle is intended to be extended and whose capabilities are to be expanded in a controlled manner.

Refactor

Improving the internal structure of the code and reducing technical debt without altering the system’s functionality.

The goal is to clarify the architecture, eliminate unnecessary dependencies, and enhance performance. The result is a system that is easier to maintain, scale, and migrate to modern environments.

Migrate to a new environment

Replatform

The system is migrated to a modern runtime environment with minimal code changes, without significant structural or functional redesigns.

The goal is to improve performance, scalability, and maintainability, while ensuring the system’s continuity in a modern infrastructure. This is a cost-effective and low-risk way to extend the system’s lifecycle and lay the foundation for future development steps.

Rearchitect

The system’s foundation is overhauled to support future requirements, such as increasing user numbers or evolving business models. This overhaul may involve, for example, migrating to a distributed cloud environment or adopting event-driven solutions.

The goal is to create a scalable and flexible system that enables rapid development and facilitates the deployment of new functionalities.

Rebuild completely

Replace

The old system is decommissioned and replaced with a new, customised solution that meets current and future needs without the constraints of legacy technology.

This approach is often the best option when the system is technically outdated, its architecture no longer supports development, or maintenance has become uneconomical.

Rebuild

The system is completely redesigned and implemented using modern technologies while preserving the original business requirements and core logic.

The result is a clear, scalable, and technically up-to-date solution that improves performance and security and supports future development.

System modernisation project in practice

UX Designer working on Resq app

Assessment and user-centred design

We map out the current state of the system: how well does it serve the size, goals, and users of the business? How up to date is it technically? With a clear overall picture, we identify the risks, opportunities, and implementation options.

Taiste developers thinking about a problem

Technical
implementation

We design and implement the system’s technical overhaul – whether that means rearchitecting, updating technology choices, changing component structures, fixing the codebase, or handling data migrations and structural changes.

Connectivity and Data Structures

We ensure that the new system works seamlessly as part of your organisation’s wider system landscape and ecosystem. Modern, well-documented API interfaces, scalable integration solutions, and tailored data structures lay the foundation for long-term success.

10 risks of system modernisation – and how to overcome them

Custom product or commercial software?

Choosing between a custom solution and off-the-shelf software is one of the key decisions in a system modernisation project. At Taiste, we specialise in solutions tailored to your company’s needs. We either build a product from scratch or adapt an open-source solution to suit your business – but we do not implement commercial off-the-shelf software such as Salesforce or SAP.

Custom system

A software solution designed specifically for the business, giving full ownership of the code and intellectual property, as well as the flexibility to adapt and switch vendors without losing the system.

Client owns software, code & IPR

Development, hosting, support

Product adapts to business needs

Vendor can be changed without losing the software

Commercial software

A ready-made product owned by the vendor, offering quick deployment with standardized modules, but requiring ongoing license fees and creating dependency on the provider.

Vendor owns software, code & IPR

Licenses, development, hosting, support

Business adapts to product

Switching vendors typically requires switching the software

A Taiste employee in a meeting

Why choose Taiste as your
system modernisation partner?

A clear roadmap from strategic goals to execution

  • A practical plan aligned with your core business objectives
  • User-centered UX design, prototyping, and testing
  • Modern architecture and framework choices that scale with your needs

All the necessary expertise in one team

  • Our team includes all the key roles: developers, UX/UI designers, DevOps specialists, project management, and quality assurance.
  • Flexible resourcing gives you peace of mind – the right experts for every stage are always at your disposal.

Smart cost-efficiency without compromising quality

  • A simple billing model based on actual work done
  • An optimised team setup that maintains high quality
  • We make use of ready-made solutions and integration libraries that speed up delivery
  • No vendor lock-in: open-source code and technologies supported well into the future

Some of our clients

The reimagined Hesburger ERP

Hesburger’s comprehensive ERP system is the backbone of its entire restaurant chain, tailored precisely to fit the company’s operations. Connecting nearly 500 locations, the solution is built to adapt to the demands of a growing business environment.

Case coming soon!

Design and development of the SoteKaista service

SoteKaista helps Finnish disability service clients to decide how they want to travel by taxi.

Read more

An institution-wide design system

A design system for one of the largest universities in Finland. Built to encourage creativity.

Read more

Is system modernisation a relevant topic for your company?

We help you choose a strategy that best supports your operating environment, business, employees, and customers. Leave a contact request, and let’s talk more!

Taiste developers reviewing code

Development principles

Scalability

We focus on the most business-critical features first, releasing them module by module – while the old system continues to operate alongside during the transition.

Collaboration

Ongoing involvement of all user groups is key to success – after all, users know their own work environment best.

Continuous feedback

No test environment can fully replicate real-world usage. An agile release cycle delivers valuable insights from the field and drives faster results.

Focus

A jointly created and regularly updated roadmap helps developers stay focused on what truly matters. A shared vision across the team is essential – it's about deciding both what to build and what not to build.

Hesburger ERP – how we increased sales by 10%

Hesburger’s comprehensive ERP system is the backbone of its entire restaurant chain, tailored precisely to fit the company’s operations. Connecting nearly 500 locations, the solution is built to adapt to the demands of a growing business environment.

A Hesburger cashier machine

Tailored solution vs. commercial software

Choosing between a custom-built solution and an off-the-shelf product is one of the most critical decisions in a system modernisation project. The final decision should always be weighed against the size of the business and the estimated business value of the renewal.

Custom-built system

  • The client owns the software, source code, and intellectual property (IPR)
  • The client pays for development, hosting, and support
  • The product is developed to meet the specific needs of the business
  • The vendor can be changed without losing the software

Off-the-shelf product

  • The vendor owns the software, source code, and IPR
  • The client pays for licenses, hosting, development, and support
  • Ready-made modules — the client adapts to the product
  • Switching vendors typically requires switching the software as well

Six approaches to a system overhaul

A system overhaul does not always mean replacing everything. There are several ways to develop or replace the current solution – from light interface solutions to a full rebuild. Below are six of the most common approaches, which we can combine case by case according to your organisation’s needs, budget, and technical situation.

Improve the
existing system

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Migrate to
a new environment

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Rebuild
completely

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Measurable value

Performance and efficiency

Modern architecture and optimised code improve system speed and reduce downtime.

Cost savings

Lower maintenance costs, more efficient infrastructure, and smoother development workflows.

Security and compliance

Solutions aligned with the latest standards reduce risk and simplify regulatory compliance.

Enhanced user experience (UI/UX)

Modern interfaces and user-centric design improve satisfaction for both internal users and customers.

Sustained competitiveness and scalable growth

A modern system enables faster response to business needs and supports continuous development.

When is it the right time for a system overhaul?

Outdated Technologies

Legacy technologies often fall short of modern business requirements. This results in decreased efficiency and challenges in building seamless integrations.

Competitiveness

Slow daily operations add up quickly — as does the gap between you and your competitors.

Talent Shortage

Skilled professionals for legacy systems are increasingly hard to find, and existing experts are gradually retiring.test environment can fully replicate real-world usage.

Growing Security Risks

Older systems become more vulnerable each year. A system renewal can significantly reduce the sleepless nights caused by security concerns.

Why choose Taiste as your system modernisation partner?

A clear roadmap from strategic goals to execution

  • A practical plan aligned with your core business objectives
  • User-centered UX design, prototyping, and testing
  • Modern architecture and framework choices that scale with your needs

All the expertise you need in one team

  • Our team includes all the key roles: developers, UX/UI designers, DevOps specialists, project management, and quality assurance.
  • Flexible resourcing gives you peace of mind – the right experts for every stage are always at your disposal.

Smart cost-efficiency without compromising on quality

  • A simple billing model based on actual work done
  • An optimised team setup that maintains high quality
  • We leverage proven solutions and integration libraries to accelerate delivery
  • No vendor lock-in: open-source code and technologies with long-term support
A Taiste employee in a meeting

Is system modernisation on your company's horizon?

Book a free consultation with our expert — together, we’ll identify a strategy that aligns with your business, people, and customers. Drop us a line — we’d love to continue the conversation.

When is it the right time for a system overhaul?

The need for modernisation should be assessed from the following perspectives:

Taiste developers reviewing code

When is it the right time for a system overhaul?

The need for modernisation should be assessed from the following perspectives:

Outdated technologies

Legacy technologies often fall short of modern business requirements. This results in decreased efficiency and challenges in building seamless integrations.

Outdated technologies

Legacy technologies often fall short of modern business requirements. This results in decreased efficiency and challenges in building seamless integrations.

Outdated technologies

Legacy technologies often fall short of modern business requirements. This results in decreased efficiency and challenges in building seamless integrations.

Outdated technologies

Legacy technologies often fall short of modern business requirements. This results in decreased efficiency and challenges in building seamless integrations.

Four Taiste employees having a meeting

Upgrade the old system – or start fresh?

Modernising a system can mean gradually replacing the existing solution, migrating the technology stack to the cloud, or launching the new system all at once.

The right approach should always be evaluated on a case-by-case basis, considering both the needs of the business environment and the technological landscape.

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