Modernizing legacy business systems using Out Systems


Our client is a leading provider of telecom solutions to world class enterprises and federal agencies. They offer a wide range of devices and services from telecom infrastructure planning to consolidated billing to transparent cloud-based management capabilities. They specialize in managed and customized communications solutions which form the digital foundation for their end customers.


n market for over 30 years, the company has built several standalone applications for their business operations like Billing, Expense management, Payment management, Provisioning, and Vendor management system, among others. These systems have been around for a long time and are built on dated technology like Visual Basic desktop. As the business grew, data management between these loosely coupled systems have become a major problem for the corporate, and there is an urgent need to modernize these systems quickly. A significant challenge for the tech team to carry this out is that these legacy systems had little to no documentation available to work from, and they have to piece the requirement and logic together from conversations with current users of these systems, and understand the flow, pain points, and usage of data. Further, as these systems are presently in use, it was essential that any modernization work does not disrupt ongoing business operations.


OutSystems ( was the platform chosen to carry out the rebuild of the company’s legacy business systems. Being a low-code development platform, it offers a key advantage of fast development and quicker time to production. Congruent deployed an offshore OutSystems development team, working closely with the customer in an Agile development environment. The Microsoft SQL database was left intact, as this is a common backend component and the central data source across all their systems. All legacy system re-writes, and new application development is being done on OutSystems, integrating with the existing SQL Database. The Congruent team developed RESTful APIs in Out Systems to integrate across the customer’s application eco systems and third-party applications. The team also harnessed OutSystems’ capabilities to integrate with third-party platforms like Salesforce, VeloCloud, Comcast, and BroadSoft.


With the choice of platform and the right offshore team, Congruent was able to modernize the customer’s Billing, Expense management, Payment management, Provisioning, and Vendor management system with high speed and productivity of development. Built in CI/CD features, ease of customization and deployments also helped the team and the customer realize quick benefits in modernizing the system, and realize benefits of using modern tech. As OutSystems has both development and runtime components, we were able to host solutions in a private environment with separate staging environments during the rebuild to allow the modernization to take place without disrupting existing business operations