Contact us
Our team would love to hear from you.
Back to blog
How to modernize a legacy application from multiple legacy systems: approach and key elements
The software development process involves many challenges that developers must solve to deliver valuable products. Transforming multiple legacy platforms into a modern solution is one of them.
In this article, we’ll examine the challenges of developing a robust application from multiple legacy platforms, how to approach the process, and the key aspects that should be considered.
Tackling the challenge of different legacy systems
Many long-established companies have likely encountered the difficulties associated with managing one or more legacy systems. As organizations expand their service offerings and create applications for each service, they often become burdened with outdated systems. These legacy systems jeopardize not only customer experience and retention but also security, compliance, effective resource allocation, and operational efficiency. Application modernization addresses the risks and issues associated with legacy systems, making software resilient and reliable.
A comprehensive approach to legacy system modernization, especially when consolidating several different systems into an all-in-one solution, aims to create a powerful new system that improves a company’s processes. To ensure the performance, flexibility, and scalability of the new application, it’s crucial to adhere to the following effective approaches.
SAFe project management
The SAFe (Scaled Agile Framework) methodology is an iterative approach to project management that is suitable for large enterprises. It involves applying Agile practices to development projects to increase flexibility and improve control. Product development is divided into different streams across various teams working independently, each with clearly defined roles and responsibilities. This structure makes complex projects easier to manage.
Migration and coexistence
When dealing with legacy systems, migration helps resolve compatibility issues and enhance the availability and security of the system. To allow the concurrent operation of the legacy systems alongside the new application before full replacement, both systems are operated in parallel. This is necessary to validate the new application against the legacy system.
Legacy Application Modernization
Explore our expertiseData access
Event-driven implementation for data access enables a system to act on events (such as the pressing of a button) as they happen. This approach is suitable for the independent development and deployment of the system, achieved through the decentralization of responsibilities. In this scenario, the new application operated independently from the legacy software, not relying on its performance, thereby enabling scalability and real-time processing and analytics.
Testing pyramid
When building a reliable, high-quality product from a legacy system, a testing pyramid is an effective approach. This includes unit, integration, and end-to-end (E2E) tests, offering a comprehensive and efficient method for maintaining and improving the application by dividing and balancing the testing efforts at different levels.
- Unit. These tests focus on individual components and functions and are run regularly.
- Integration. Integration tests are run less frequently; they check how different components and modules interact.
- E2E. E2E tests are used to assess the overall application and are run after each development milestone.
Key infrastructure elements
The following infrastructure elements play a key role in transforming multiple legacy systems into a powerful modern solution.
Front-end functionalities
As the cornerstone of customer engagement, the client-facing side of an application should be well-designed, intuitive, and functional. Legacy app modernization provides an opportunity to add features that were lacking in the old system and improve the interface, enhancing user experience.
Admin panel
An admin panel is a core component of an application that gives administrators the tools they need to manage, control, and configure the system. It also displays all the data the system is designed to collect, such as customer details, operational status, and more. Admin dashboards allow companies to monitor and analyze product performance, facilitating prompt decision-making and action.
Single sign-on (SSO)
SSO is an authorization protocol that allows users to log into multiple applications with one set of credentials. When transforming multiple legacy systems into a modern solution, SSO can streamline the user experience, enhancing both convenience and security while the legacy application transformation is in progress.
Security
Security is one of the main issues with legacy systems. When modernizing outdated software, it’s important to integrate security measures from the early stages to ensure that the new solution meets all requirements.
Notification and alerts
This is an important functionality for enhanced user experience. The system should be able to send notifications through different channels, such as push notifications and email, and alert users about relevant events (changes in policy, new features or services, proposals, etc.).
Reporting and analytics
Data plays a significant role in helping companies develop strategies. Systems require reporting capabilities to collect and present data in a clear, structured format, which enables a comprehensive view of business dynamics. With data analytics capabilities, companies can gain valuable insights and identify patterns essential for informed decision-making.
A centralized data warehouse and Microsoft Power BI allow collecting and analyzing data from the divisions scattered across the USA.
Logging and monitoring
Logging and monitoring ensure that the system is secure, fully functional, and demonstrates optimal performance. This unified approach to tracking and managing system activities enables prompt identification and resolution of issues and errors, ensures the system is compliant with the relevant regulations, detects malicious activities, and prevents or mitigates cyberattacks.
Localization and internationalization
If the new application is intended for an international audience, localization and internationalization are crucial aspects of the development process. Localization and internationalization frameworks ensure dynamic content translation based on regional and user settings. The modernized application should support right-to-left languages and layouts for different text directions. By setting up a localization platform integration with the code repository, new and updated translations can be automatically integrated into the application, accelerating time to market.
How to ensure app security
When it comes to modernizing a legacy system, let alone multiple systems, security is one of the primary considerations. The new application should address the faults and vulnerabilities of the outdated software, protect sensitive data, comply with local legal requirements like GDPR, and prevent cyberattacks. This is achieved by integrating security measures throughout the entire application modernization process.
Compliance and standards
Each industry has a set of policies or security requirements that regulate data protection and privacy. Noncompliance with these standards can lead to lawsuits and financial and reputational losses.
Dependency management
Systems consist of numerous interdependent components, such as libraries, frameworks, and other systems. To avoid errors and security breaches when modernizing legacy systems, these dependencies must be properly managed. There are tools designed to automate dependency checks and provide security alerts, ensuring the security and reliability of the system.
Error monitoring
Error monitoring tools facilitate real-time tracking of problems, allowing for quick detection and resolution and offering insights into their underlying causes.
Continuous integration/continuous delivery (CI/CD) security integration
Incorporating security measures into the CI/CD pipeline enables continuous monitoring and helps identify potential security threats and vulnerabilities in the system, protecting it against cyberattacks.
Data privacy
Access to sensitive data should be controlled throughout the development process. Secure storage and data backup are also key measures to ensure data safety and availability in case of any disruptions.
As cutting-edge technologies are developing at a staggering pace, so are cybersecurity threats, putting organizations heavily reliant on such technologies at risk. Business owners seek assistance from cybersecurity experts, who know how to efficiently respond to cyberattacks, and combat these threats using artificial intelligence.
How to provide scalability
Legacy systems typically lack scalability, which impacts performance, workload handling capacity, infrastructure costs, functionality, and even customer satisfaction. Several practices can ensure that a modernized application is scalable and resilient, guaranteeing high availability and consistent performance.
Microservices architecture
Microservices architecture involves breaking the system down into independent services. This approach facilitates scaling each service separately according to specific needs, thereby avoiding unnecessary resource expenditure.
Distributed caching
Distributed caching involves storing data across multiple nodes of a network system. This is crucial for applications with high data loads and volume because distributed caching increases processing power, lowers response time, and reduces the load on databases.
Asynchronous processing
Breaking down procedures into independent tasks allows for asynchronous processing, so processes can be handled separately without having to wait for other tasks to be completed. This improves system performance and enables efficient scalability.
Performance monitoring
Continuous monitoring of system performance is essential for promptly identifying and resolving any issues, including scaling bottlenecks. This ensures that the system can effectively manage increasing workloads.
DevOPs Services
Explore our expertiseConclusion
Legacy app modernization is an important step toward new opportunities and business growth. Modernized solutions come with enhanced security, improved performance, upgraded flexibility, and many other benefits. Though modernization is a complex process, a skilled development partner can ensure the process runs smoothly and the new system meets all requirements and objectives. Ready to launch your project? Contact our experts to learn more and get started.
F.A.Q. about legacy application
A legacy system or application is computing software that is based on outdated technologies but is crucial to a company’s operations. These systems are characterized by limited flexibility, scalability, and integration opportunities as well as low performance and weak security.
There are seven main application modernization approaches: encapsulation, rehosting, replatforming, refactoring, rearchitecting, rebuilding, and replacing. The choice of legacy application modernization strategy depends on the company’s needs and requirements, the current state of the system, and the budget.
The approach to legacy application modernization determines the process. You can begin by teaming up with a skillful partner who will evaluate the complexity of the project, define the goals, and develop an effective plan. Contact our experts to begin collaboration.
STILL HAVE QUESTIONS?
Can’t find the answer you are looking for?
Contact us and we will get in touch with you shortly.
Blog
Related articles
Top 7 frameworks for building AI agents: which one fits your use case?
Every company wants its workflows to be smarter and more efficient, and AI agents are the ideal solution. These intelligent systems act like loyal employees that operate around the clock, orchestrate a myriad of unrelated workflows simultaneously, and solve big-picture problems independently. But what if building a ground-up AI agent is too costly for your business? AI agent frameworks offer more cost-efficient and time-saving options.
Generative AI consulting company: does technology advisory make a difference?
Modern businesses have discerned the true value of generative AI: the democratization of art, automated workflows, and substantial cost savings. While some companies rush to adopt the technology no matter the risks, others stay on the sidelines, discouraged by challenges. So, how do you integrate generative AI safely and effectively, turning it into a powerful tool rather than a risky liability for your business? Generative AI strategy consulting is the answer.
What it really costs to migrate to OCI and how to maximize savings
Cloud adoption does not guarantee cost-efficiency; in fact, it often results in higher expenses due to reactive decisions, lack of financial governance, and other factors. To prevent this, an accurate assessment of all factors and hidden costs is essential.
Hackathon behind the scenes: Insights from our software engineer
In April 2025, EffectiveSoft held its second hackathon around generative AI, where analysts, developers, designers, testers, and other professionals teamed up to turn their ideas into working prototypes within two days. For one of our software engineers, Uladzimir Poddubny, it was a first-time experience.
LLM сomparison: How to choose the right model for your business
Major companies like Spotify, Salesforce, and Duolingo are already using large language models (LLMs) to improve podcast recommendations, facilitate financial analytics, and deliver hyper-personalized experiences to global users. Following their lead, more businesses have begun integrating LLMs into their operations. But with an impressive list of large language models, choosing the right one becomes a challenge.
EffectiveSoft welcomes a new global HR director
The EffectiveSoft team is expanding and strengthening its expertise with the addition of Anna Aleksina as our new global Human Resources director. We are thrilled to welcome Anna, an experienced professional dedicated to fostering a strong company culture and effectively navigating the challenges of the global tech workforce.
Low-code development: changing the game with Oracle APEX
As technology evolves, software development is becoming more accessible to businesses and individuals. Low-code practices allow developers to build web and mobile applications with minimal coding efforts, saving time and resources. One standout low-code service is Oracle Application Express (APEX), which is gaining traction for its efficiency and ease of use.
Blazor: transforming the trajectory of app development
Creating an app is like constructing a building: both require strategic planning, upfront investment, and the use of versatile tools. But what if a single tool could make app development more cost-efficient, streamlined, and native-like? That’s where Blazor steps in.
A new milestone achieved: EffectiveSoft expands its talent pool of Certified Azure AI Engineers
Certification plays a key role in specialists’ career growth and development. However, EffectiveSoft recognizes that supporting its employees in obtaining prestigious designations and staying current with disruptive technology trends isn’t just about building skills internally—it’s about prioritizing clients. Every upskilling initiative revolves around our clients’ unique business needs and unresolved challenges.
Healthcare data visualization: benefits, examples, and tools
The healthcare industry is awash in data. From patient records and clinical trials to operational metrics and public health trends, the sheer volume of information can be overwhelming. Data visualization helps make complex medical data easily digestible with visual formats like charts, graphs, and interactive dashboards. This allows healthcare professionals to quickly obtain the required insights, make decisions with more confidence, and ultimately improve patient care.
EffectiveSoft welcomes its new Technology Director
EffectiveSoft is thrilled to welcome Vlad Movsikov as our new Technology Director! With a strong background in software engineering and management, Vlad is passionate about building teams, delivering innovative solutions, and bridging the gap between technology and business strategy.
Cloud pricing comparison: choosing the right cloud provider
Choosing the right cloud service provider requires careful consideration due to the vast array of options, each with unique features and capabilities. Pricing significantly influences the decision, as organizations strive to balance their requirements with their budget to find the perfect fit.
Burning questions about mobile app testing: insights from our QA specialist
Mobile app quality assurance (QA) testing plays a pivotal role in ensuring the reliability and optimal performance of the apps we use every day. QA is more than just detecting and fixing bugs. QA specialists face various testing challenges, including choosing the most suitable tool, ensuring app usability, and guaranteeing accessibility. The EffectiveSoft team approaches these challenges with dedication and expertise.