What is a legacy system?

A legacy system, also known as an old system, is an IT solution that has grown over the years and still controls important business processes, but is no longer technically up to date. Such systems are often based on outdated technologies, are difficult to maintain and lack flexibility. They cause high costs and make it difficult to integrate modern applications. Replacing a legacy system means gradually modernizing these structures and thus creating the basis for future-proof IT.

How can AI support us in modernizing legacy systems?

Today, AI is an indispensable part of any modernization. It accompanies the entire process when it comes to replacing a legacy system: From a deep understanding of the existing legacy systems, the development of domain knowledge and the creation of tests through to implementation. Our employees use AI consciously and efficiently. This not only makes the modernization of your legacy system more predictable and secure, but also significantly faster.

What challenges are there when replacing legacy systems?

The main challenges are secure data migration, integration into existing processes and avoiding downtime. There is often a lack of documentation and up-to-date system knowledge, which makes planning more difficult. Technical dependencies and coordination between specialist departments and IT also make the replacement process complex.

How long does it take to replace a legacy system?

The duration of a replacement depends heavily on the size of the company, the complexity of the existing system and the scope of the data to be migrated. While smaller applications can often be modernized within a few months, the replacement of extensive or production-critical legacy systems takes several years. Old and new systems often run in parallel for a while or the new systems are introduced gradually, for example initially at central locations.

White computer keyboard on a blue background; a bright pink cloud of digital circuits rises from the keyboard, connected by fine conductors/wire lines.

Replace legacy system

We transform your legacy systems into flexible, future-proof solutions.

Why you should replace your legacy system

IT systems that have grown over the years form the backbone of central processes in many companies and at the same time are increasingly becoming strategic brake blocks. These so-called legacy systems are based on outdated technologies, code that is difficult to maintain and rigid structures. Legacy systems often fulfill their core function, but reach their limits as soon as new requirements for data availability, security or integration arise.

With MaibornWolff, you can make the change: we develop individual strategies to replace your legacy systems strategically, with AI support and low risk. We modernize mature IT landscapes, combine old and new technologies and thus create the basis for your long-term digital development.

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Replace your old system: Your advantages with MaibornWolff

Implementation at the right pace

We offer customized solutions that are established at a pace that suits the customer.

Step-by-step modernization

We modernize legacy systems step by step and ensure stable operation throughout.

Continuous quality assurance

In each phase, the results are compared between the old and new systems, especially in production-critical environments.

Extensive understanding of technology

We combine in-depth technology expertise with experience from complex transformation projects in various industries.

Technical signs

The system reacts noticeably slower, fails more frequently or displays error messages.
Frameworks, databases or programming languages used are no longer supported.
Interfaces to other applications are outdated or do not exist at all.
New technologies, AI services or cloud services can only be integrated with great effort.
Security updates are missing and the system is becoming increasingly vulnerable to attacks.

Functional signs

Organizational signs

Reduce costs: The elimination of old hardware and inefficient processes significantly reduces maintenance costs, license costs and operating costs.
Increase agility: Modern system architectures make it possible to develop new functions more quickly and adapt them flexibly.
Improve data quality: Standardized interfaces and up-to-date data models create the basis for transparent, reliable information.
Increase security: Current software and cloud solutions offer modern security mechanisms, automatic updates and clear compliance structures.
Strengthening innovative strength: A modern IT landscape creates space for new digital services, AI applications, intelligent automation and data-based business models.

Understanding before change

Every legacy system is unique. We analyze the code base, data flows and interfaces to understand technical risk and business dependencies. We make targeted use of AI and use Agentic Domain Discovery to gain a very deep understanding of your legacy system. This forms the basis for a robust migration strategy.

Gradual modernization instead of big bang

We migrate in stages and initially run the old and new systems in parallel. This allows us to continuously compare results, validate data and safeguard functions. This approach reduces the risk of failure and enables a smooth transition.

Architectures with a future

Our solutions follow modern principles such as domain-driven design, hexagonal architecture and microservices. We create clear interfaces and ensure that systems remain scalable and maintainable in the long term.

Targeted renewal of technology

Whether migrating monolithic applications to container-based environments with Docker and Kubernetes, switching from old DB2 databases to PostgreSQL or building modern web front-ends with React or Angular: We modernize in a targeted manner where it brings real added value. Our customers benefit from our expertise in the latest AI-supported techniques and technologies. This significantly reduces the migration time.

Quality through continuous validation

Automated tests, monitoring and regular comparisons between the old and new systems safeguard every development step. Entire systems can be validated using AI-supported tests, creating a wide-ranging safety net. This makes the new solution not only functionally identical, but also more efficient, stable and future-proof.

Cooperation at eye level

Technical transformation can only succeed through dialog. We work closely with specialist departments, IT and management. We translate complex interrelationships into comprehensible decisions and accompany the entire process.

Our references and projects

How can a legacy system be replaced while safeguarding business operations? Our references provide an insight into projects in which mature structures were turned into powerful, future-proof systems.

To all references

TK Elevator: Health Check Connectivity for the IoT gateway of elevators

The IoT gateway is the linchpin for the increasing digitalization of elevators. Within 6 weeks, we put the quality of the software, hardware and operation through their paces.
To the TKE reference

TK Elevator: Health Check Connectivity for the IoT gateway of elevators

IoT gateway

connects elevator with IoT platform

Code analyses

and 22 interviews & workshops

Optimization

of the connectivity of the gateways

To the TKE reference
inCTRL Solutions: Modernization of the IoT platform for water treatment plants

We are making the opsCTRL IoT platform highly resilient, maintainable, and capable of further development. New functions can be integrated into products more quickly.
To inCTRL reference

inCTRL Solutions: Modernization of the IoT platform for water treatment plants

Renovation

of the IoT platform

Maintenance & new features

go hand in hand

Change code quickly

thanks to CI/CD pipelines

To inCTRL reference
Schöck components: Improvement of the requirements process

Together with MaibornWolff, the construction industry specialist optimized the requirements management of its Scalix design software. Thanks to the digital design approach, the technical requirements were re-specified and the software was further developed in a user-centered manner. The aim is to continuously increase user satisfaction and integrate internal and external interests. Read more about the methodology and results now!
See Schöck Bauteile reference

Schöck components: Improvement of the requirements process

Project duration

since 2022

Team size

2-3 Digital Designer:inside

In 2024

Scalix replaces old software

See Schöck Bauteile reference
BMW Group: Replacement of a production-critical legacy system

20-year-old system, new digital future. We gradually migrated production software to a flexible architecture. After two years, central plants were running on the new solution - stable, fail-safe and ready for the challenges of tomorrow.
See BMW Group reference

BMW Group: Replacement of a production-critical legacy system

Project duration

Mid-2018 to the beginning of 2024

Team size

25 employees

Legacy system

replaced after 20 years

See BMW Group reference
ifm services: Remote maintenance of systems and machines

Maintenance, anywhere and at any time - together with ifm services, we developed a remote access solution for industrial plants. A small, agile team created a full-stack cloud application that combines intuitive operation and secure connectivity. The product celebrated its premiere at HMI 2024.
See ifm services reference

ifm services: Remote maintenance of systems and machines

Project duration

since March 2023

Remote Access

integrated in platform

Team

5 Developers

See ifm services reference
Planning systems: Optimizing the capacity utilization of pressing plants

Maximum capacity utilization, minimum costs: Our customer relies on a central planning system for pressing plants. We have been supporting its further development with .NET Core, GraphQL and PostgreSQL for over ten years. Now the journey is moving to the cloud - for greater scalability, flexibility and efficiency.
See reference

Planning systems: Optimizing the capacity utilization of pressing plants

>10 years

Customer support

Technological modernization

Cloud-ready platform

Efficiency through data

Site-specific cost planning

See reference
Global workforce planning system

How do you achieve globally harmonized workforce planning? With a modern web application based on domain-driven design and hexagonal architecture. Event sourcing ensures transparent traceability, while Azure and Quarkus provide stability and scalability. The result: a flexible, future-proof solution.
See reference

Global workforce planning system

Team size

up to 8 employees

Domain Driven Design

development approach

Microsoft Azure Cloud

allows easy roll-out of new versions

See reference
Supply chain management: Reducing cloud operating costs by 50 percent with FinOps

We have made the supply chain management system for an international industrial company more scalable and robust through process modernization, improved monitoring, automation and rightsizing. Targeted optimization of the infrastructure reduced oversizing and unnecessary resources - the platform is more stable.
To the FinOps reference

Supply chain management: Reducing cloud operating costs by 50 percent with FinOps

Lowering

of the cloud operating costs

Fast

to the new release

More transparency

and control

To the FinOps reference

FAQs: Frequently asked questions about replacing legacy systems

What is a legacy system?

A legacy system, also known as an old system, is an IT solution that has grown over the years and still controls important business processes, but is no longer technically up to date. Such systems are often based on outdated technologies, are difficult to maintain and lack flexibility. They cause high costs and make it difficult to integrate modern applications. Replacing a legacy system means gradually modernizing these structures and thus creating the basis for future-proof IT.
How can AI support us in modernizing legacy systems?

Today, AI is an indispensable part of any modernization. It accompanies the entire process when it comes to replacing a legacy system: From a deep understanding of the existing legacy systems, the development of domain knowledge and the creation of tests through to implementation. Our employees use AI consciously and efficiently. This not only makes the modernization of your legacy system more predictable and secure, but also significantly faster.
What challenges are there when replacing legacy systems?

The main challenges are secure data migration, integration into existing processes and avoiding downtime. There is often a lack of documentation and up-to-date system knowledge, which makes planning more difficult. Technical dependencies and coordination between specialist departments and IT also make the replacement process complex.
How long does it take to replace a legacy system?

The duration of a replacement depends heavily on the size of the company, the complexity of the existing system and the scope of the data to be migrated. While smaller applications can often be modernized within a few months, the replacement of extensive or production-critical legacy systems takes several years. Old and new systems often run in parallel for a while or the new systems are introduced gradually, for example initially at central locations.

Why MaibornWolff?

As one of the most innovative IT service providers with a great passion for AI, we focus entirely on the project business and individual software development - without our own products. To stay at the forefront, we continuously invest in our team of digital technology engineers and develop digital solutions that are well thought-out, efficient and reduced to the essentials.

Our principle: simplicity instead of complexity. We only develop what is really needed - tailor-made, useful and reliable. Our results speak for themselves. With over 800 large-scale systems and more than 10,000 person-years of experience in high-end software engineering, we are one of the few who can reliably implement even the largest and most complex IT landscapes. Thanks to close partnerships with leading hyperscalers, our customers operate their solutions in today's most modern and powerful environments.

Less technology. Better Business.

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