Our client
A U.S.-based company providing funding to small businesses relied on project pages that had been built by a freelancer without a proper architectural foundation. Function features and code were so tightly coupled that even small changes introduced new bugs, performance lagged, and maintenance costs grew.
The biggest bottleneck was the “Deal Page,” where employees spent up to 80% of their time. Instead of enabling productivity, it slowed it down, with long load times, unstable workflows, and an inability to adapt to new business requirements. This situation highlighted the urgent need for legacy system modernization.
We had seen a similar issue with a European energy efficiency company. Their challenge was seamless migration across Azure, AWS, and on-prem without vendor lock-in. By refactoring into microservices, adding abstraction layers, and containerizing services, migration time by 4x and cut cloud resource costs by 25%. Different industries, but the same challenge: outdated architecture limiting agility.
Challenges and impact of legacy system limitations on business
The client faced a long list of challenges that prevented them from using the full potential of their system and growing:
- Legacy architecture limits growth: outdated systems blocked innovation and scaling, while simultaneous work by multiple employees caused frequent save conflicts and data inconsistencies.
- High maintenance costs: ongoing bug fixes and patchwork updates drained budgets. Businesses needed to reduce cost of legacy software maintenance.
- Dependence on freelancers or small teams created a poor experience: ad-hoc fixes, chaos in architecture, undocumented code, and constant risks of instability with every change. The client realized they needed to replace this with a permanent support team, clear ownership, and documented processes spanning from discovery to delivery.
- Long release cycles: the absence of CI/CD pipelines and QA automation slowed down delivery.
- Inability to react quickly: despite repeated attempts, the company failed to meet market demands and investor expectations within reasonable timeframes.
- Operational bottlenecks: increased page volume and user load led to instability and data conflicts.
- Low flexibility: introducing new features, adding products, or expanding into new markets demanded excessive time and resources. The rigid architecture made even minor enhancements slow and costly, while system limitations capped usage at around 30 concurrent users, effectively blocking customer growth and scalability.
- High operational risks: frequent bugs and system instability created uncertainty.
- Eroding competitive edge: slow transformation allowed rivals to gain ground.
Our approach
We’ve seen many mid-sized fintech companies in the United States struggle with growth and scalability due to outdated systems. To remain competitive, they require legacy application modernization as part of broader legacy modernization strategies. This process is not just about fixing code but about accelerating digital transformation with legacy modernization to reduce costs, improve delivery, and unlock sustainable growth. It also included offloading part of the data processing to dedicated databases and migrating the project to cloud environments, enabling better monitoring, cost efficiency during load peaks, and reduced risks of system unavailability for end users.
NetLS assembled a dedicated development team to drive the company’s transformation. We began with a step-by-step legacy system modernization approach that started with a discovery phase to surface architectural issues, then moved to a complete redesign of both the interface and the system’s backbone. Our team started with the page’s core logic, data flows, and integration layers, ensuring a stable foundation for future scalability and innovation.
Rather than patching existing flaws, we rebuilt the platform from scratch, separating functionality into independent modules for data storage, calculations, integrations, and document handling — a modular approach to legacy system modernization. In addition, we gradually replaced each feature after UAT on production using an Omni-Channel routing approach.
In structuring the modernization effort, we adhered to three core principles designed to balance immediate impact with long-term scalability. The first priority was improving UI/UX in legacy application modernization — with an adaptive UI built on a mobile-first approach — by redesigning system interfaces to enhance usability, streamline navigation, and increase operational speed.
Then, we executed a transition from monolith to microservices, enabling greater scalability, architectural flexibility, and responsiveness to evolving business requirements — while achieving cost efficiency and more agile use of server resources.
To safeguard delivery and ensure reliability, we embedded phased testing, QA & automation testing, and rigorous quality control from the earliest development sprints.
To ensure long-term stability and scalability, we implemented a modern technology stack. With UI enhancement as the top priority, we selected Knockout.js for its lightweight MVVM framework, which supports dynamic, data-driven interfaces, seamless two-way data binding, and rapid development of interactive components without unnecessary overhead. With Knockout.js, UI logic ensures a stable user experience even in low-bandwidth or unstable network conditions.
The complete technology stack included:
- ASP.NET and .NET Framework with C#, Entity Framework
- Microsoft SQL Server for data management via store procedure
- JavaScript, Knockout.js, Bootstrap, and CSS for the front end
- SignalR for real-time features for sensitive financial data
- Integrations with HubSpot and Salesforce extended business capabilities
- Azure and Azure Monitor provided resilience and transparency
- QA and automation testing supported by NUnit, Visual Studio, Swagger, SoapUI, and Postman guaranteed quality from day one
Results and business value
The modernization initiative was not only a technical upgrade but also a strategic enabler for the client’s long-term business objectives. By addressing architectural inefficiencies and introducing a modular framework, the project delivered outcomes that went beyond operational improvements. The rebuilt system became a catalyst for productivity, cost optimization, both in personnel time and cloud resources, and competitive differentiation in the financial services market.
The results were both measurable and transformative:
- 6x faster page load times, driving higher employee productivity.
- Delivered at 65% of the previous cost — 35% cheaper for the same features.
- Approximately 30 legacy bugs were resolved, resulting in increased overall system stability.
- Lower server costs through optimized infrastructure.
- Clearer workflows and improved navigation, reducing operational complexity.
Beyond immediate gains, the project also strengthened the company’s strategic position:
1) Impact on the client’s business
- Productivity & efficiency: thanks to the agreed and well-executed Discovery phase, the delivery of the same features became more efficient, with reduced time wasted on daily operations, lower development and maintenance costs.
- Stability & scalability: modular architecture enables secure growth, seamless integration of new services, and future-ready infrastructure. Now, the system can handle higher transaction volumes and more users without risk.
- Strategic growth: modern technologies and optimized processes open opportunities for revenue expansion, stronger market positioning, and long-term competitiveness.
2) Impact on the creditor using the modernized system
- Enhanced experience: clean UI/UX, elimination of critical bugs, faster page loads, and intuitive workflows.
- Reliability: reduced risk of downtime or unavailability, even during peak loads.
- Confidence & trust: stable platform for processing more deals, enabling parallel work without conflicts, and scaling beyond the previous cap of ~30 users
Beyond the numbers, employees experienced smoother collaboration with parallel editing, while management gained confidence in a scalable, flexible system built for the future. What was once an uncontrollable legacy burden became a transparent, modern solution aligned with the company’s growth strategy.
This project demonstrates how a focused legacy system modernization initiative in fintech can replace inefficiency with scalability. With the right combination of a dedicated development team, legacy application modernization, cloud-native architecture on Azure, and QA automation, NetLS's dedicated development team helped a financial services company not only stabilize its operations but also prepare for sustained growth in a competitive market.
Ready to turn your legacy systems into a growth engine?
At NetLS, we help financial services companies accelerate digital transformation with proven legacy modernization strategies based on the Zachman Framework, from step-by-step architecture redesign to scalable microservices and automation. Explore Our Pricing to see how modernization fits your budget, or book a call with our experts to discuss a tailored approach for your business!