At Catapult, we propel businesses forward with tailored legacy system modernisation and legacy system migration services. Our transformative approach blends innovative technology, collaborative expertise and customer-centric strategies to ensure your business stays agile, efficient and competitive. We’re here to assist you with:
- Legacy System Reengineering: We’ll help you rebuild all or parts of your systems using modern engineering practices. This approach reduces technical debt and delivers high-quality software that can be updated without any downtime, all while being cloud-compatible. We’ll start with your MVP features to ensure a solid foundation.
- Data Migration: Moving data from old systems to new ones can be intricate and time-consuming. We ensure a smooth transition through meticulous mapping, cleaning, and validation of your data. This guarantees that your new system has accurate information in the right format and complies with GDPR regulations.
- APIs and Integrations: We specialise in creating and managing customised interfaces for both new and existing services. Our solutions add an extra layer of security and resilience, allowing you to integrate services that expose data and capabilities, whether privately or publicly.
- User Experience (UX): We’ll map out customer journeys with a user-centred design approach, optimising your business processes along the way. Our services include designing a system component library, implementing analytics for better customer satisfaction, promoting self-service, and enhancing operational efficiency to drive user adoption
Our build-operate-transfer (BOT) model means your new service is always production ready and we will take care running it until you're ready to take ownership.
Ready to redefine digital transformation

Ready to redefine digital transformation
Ready to redefine digital transformation Unlock the secrets to successful legacy system modernisation.
Overcoming legacy system challenges: The Aldermore case study
Aldermore Bank faced several challenges in upgrading its legacy system, including complex data migration, integration issues and user adoption concerns. Ensuring GDPR compliance and seamless compatibility with existing applications was crucial, as was providing comprehensive training to ease the transition for employees.
Additionally, the responsible decommissioning of outdated systems and managing unexpected costs required careful planning. By partnering with Catapult, Aldermore successfully navigated these challenges, benefiting from best-practice insights, tailored solutions and a fixed-price engagement model that ensured a smooth and cost-effective modernisation process.
Curious how we helped Aldermore overcome legacy system challenges? Read the full case study to see how our tailored solutions made all the difference.
Why modernise legacy systems?
Outdated legacy computer programs and software applications create barriers to growth, limiting scalability, flexibility and operational efficiency. They also expose businesses to security vulnerabilities, compliance risks and rising maintenance costs.
By upgrading legacy systems with Catapult, you can:
- Improve efficiency and streamline business operations
- Reduce the risks associated with legacy software modernisation and security vulnerabilities
- Enhance data integration and support cloud computing adoption
- Boost scalability while ensuring cost-effectiveness and measurable ROI
Our solutions don’t just update your technology — they align with your business goals.
Reduce your tech debt, fast.
Signs your business needs legacy system modernisation
Your team might be resistant to change because it’s used to existing systems and processes. However, it’s important to consider how a transformation could improve productivity.
Modernising legacy systems is crucial to ensure your business can adapt to the changing needs of customers. Legacy applications and software, often built on outdated technology, prevent efficiency, flexibility and innovation, while also resulting in scalability and security limitations.
When you use outdated systems and end-of-life legacy software and hardware, you're exposing your business to security and compliance risks that could lead to unscheduled downtime, hacking, data loss and fines. These issues often result in low quality services and a poor customer experience, which will negatively impact growth and revenue.
As trainers teach new employees about current systems and older employees leave, the company may experience a shortage of knowledge about legacy systems. To attract talent and investors who can help meet business goals, businesses must modernise.
Legacy modernisation is crucial when businesses struggle with outdated technology. If your system:
- Is incompatible with modern application modernisation strategies
- Runs on an outdated legacy computer program or unsupported technology
- Increases security risks because of lack of updates
- Limits business continuity, data integration and innovation
- Requires high maintenance costs that outweigh its value
Then it’s time to consider a structured legacy application modernisation plan. Our proven approach enables businesses to accelerate growth while reducing risk and complexity.
The importance of legacy software migration
At Catapult, we believe that legacy software modernisation should be seamless and strategic. Many businesses struggle with outdated technology that limits efficiency and innovation, while increasing compliance risks. By modernising systems, businesses can find modern technologies and architectures that improve performance, streamline processes, and reduce tech debt to ensure flexibility and enhance security.
Modern, responsive, Agile businesses always have a competitive advantage. They can thrive in the constantly changing socio-economic and technological landscapes that drive customer needs and expectations.
Our expert-led approach helps businesses:
- Achieve business objectives through scalable, future-proof solutions
- Reduce security vulnerabilities and operational inefficiencies
- Improve cost-effectiveness with cloud computing and automation
- Ensure business continuity and resilience in a fast-evolving market
By transforming legacy systems, we empower businesses to thrive in the digital era.
When is the right time to upgrade legacy systems?
Making an informed decision about legacy system migration is critical. Key factors to consider:
- Performance: Is your system slowing down, crashing, or limiting productivity?
- Compatibility: Does it integrate with modern application modernisation frameworks?
- Scalability: Can it support business growth and operational demands?
- Cost-effectiveness: Are maintenance and support costs becoming excessive?
If your system is impacting efficiency, security, or customer satisfaction, it’s time to modernise.
The benefits of upgrading legacy systems
Upgrading legacy systems unlocks:
- Scalability: Cloud computing and improved system integration
- Operational efficiency: Faster response times and streamlined workflows
- Enhanced security: Proactive risk management and compliance support
- Data-driven decision-making: Optimised insights and automation
- Future-ready infrastructure: Adaptable, innovative solutions
Legacy system modernisation isn’t just about technology — it’s about empowering teams, reducing complexity and driving sustained business growth.
Our approach to legacy system migration
At Catapult, we follow a structured, human-centered approach to ensure smooth, effective legacy software modernisation. Our process includes:
Overcoming barriers to modernising legacy systems

Overcoming barriers to modernising legacy systems
Overcoming challenges in legacy system modernisation
Modernising legacy computer programs comes with challenges, but Catapult helps businesses overcome them efficiently:
- Data migration: Transferring data from old to new systems can be complex and time consuming. Thorough mapping, cleaning and validation of data ensures that the new system has access to accurate data in the correct format and is GDPR compliant.
- Integration issues: Integrating new systems with existing applications can be challenging. Working with a software development expert enables businesses to build a custom solution that ensures compatibility.
- User adoption: Employees that are comfortable using existing software may struggle to adapt to the new system. Providing comprehensive training and support is key to a smooth transition and minimal disruption during the transition.
- Legacy system decommissioning: Once the migration is complete, businesses must decommission the legacy system responsibly. Software experts can support during this process to ensure compliance with regulations.
- Unexpected costs: Migrations can incur unexpected costs caused by issues around data clean up, customisation, training or other issues that lead to disruption. Working with an expert that offers fixed outcome, fixed price engagement models ensure clear accountability and helps avoid costly setbacks.
Partnering with Catapult can increase the chances of successful software modernisation and system upgrade. We can use our expertise to navigate challenges, provide valuable insight into best practice and offer tailored solutions that meet your needs.
How Catapult supports your legacy system modernisation
Understanding the best way to modernise your systems can be difficult, so Catapult can provide hands-on support to guide businesses through the process.
Catapult works alongside businesses to modernise IT systems as part of their digital transformation plans, ensuring any upgrades directly align with business goals and meet the needs of both internal users and customers. Our expert consultants and software testing engineers will be there to help keep the plan on schedule, upskill teams and futureproof processes.
For example, when The Maritime Coastguard Agency wanted to become the best performing and fastest growing international flag state, it decided to digitalise the UK Ship Register to reduce internal administration and enhance CX.
Supported by Atlassian tools, Catapult took an Agile approach to deliver a cloud-native, modular solution that enables 24/7, self-service vessel registration and management.
Our client success stories, such as the Maritime and Coastguard Agency’s award-winning digital transformation, highlight our ability to deliver impactful, scalable solutions.
Why choose Catapult for legacy system modernisation?
Catapult is more than a service provider — we are your strategic growth partner. We specifically design our solutions to accelerate business transformation through innovative and scalable strategies. We simplify complexity, making application modernisation a seamless process.
Our approach ensures measurable return on investment by reducing risk and improving efficiency. Additionally, we empower teams and enhance performance, fostering user adoption and overall satisfaction.
As a trusted technology partner, we provide:
- Tailored solutions for bespoke software and app modernisation
- Expert guidance through every stage of legacy system modernisation
- Proven results in optimising performance, security and efficiency
- Future-ready strategies that ensure long-term sustainability
Ready to develop bespoke software?
Don’t let outdated technology hold you back. Partner with Catapult for a seamless, secure and cost-effective legacy system migration and app modernisation strategy.
Contact our team today to discuss your legacy modernisation plan and take your business to the next level.