We Renewed the Critical Systems of One of Europe's Busiest Airports
A flight information appearing incorrectly or late at an airport is not a simple software bug; it means thousands of passengers, dozens of planes, and an entire operation being disrupted. At Istanbul Sabiha Gökçen, one of Turkey's and Europe's busiest airports, we renewed exactly these critically sensitive systems. We cleared the technical debt accumulated by aging technology, took performance to the top, and established a future-ready architecture. While doing this, we didn't stop the airport's continuously running digital ecosystem for even a moment.
Featured Results
By deeply analyzing the airport's critical workflows, we permanently fixed errors in existing systems. We then completely revamped the old architecture with next-generation technologies capable of withstanding high traffic loads with zero latency. We carried out development in two main lanes. First, we developed the Flight Information Management Portal—which delivers error-free flight information to passengers and staff—from scratch using Phexum architecture. Second, we modernized the food and beverage applications in the terminal to handle the load during peak hours. Ultimately, system interruptions were eliminated, manual error risks dropped to zero, and operational coordination reached its maximum speed.
Who the Client Is and the World They Live In
Istanbul Sabiha Gökçen International Airport (ISG) is one of the busiest airports in Turkey and Europe, managing a massive passenger and flight traffic every day. In aviation, time management and data accuracy are the heart of the operation. A one-second delay or a single piece of faulty data can lead to cascading disruptions. The fundamental challenge of this world is continuity. The system must run 24/7, cannot be stopped for maintenance, and does not tolerate errors. Added to this is the technical debt accumulated over time; old technologies slow down, become fragile, and clog during heavy traffic. Therefore, the engineering challenge here is clear: renewing a running, critical system without stopping it, right when its load is highest.
Cross-Cutting Concepts and Architecture
The first concept running through this entire project is real-time. At an airport, flight data flows continuously from different sources: airlines, the tower, and ground services. The Flight Information Management Portal we developed from scratch gathers this raw data in a central pool. Operations personnel quickly check and approve the data from a dynamic interface. The approved information is then transferred in real-time to relevant operation screens and external systems via instant messaging and data queue technologies. An approval made by one personnel instantly appears on another's screen. This is a real-time data streaming and verification problem: carrying data not just fast, but also verified and error-free. The benefit is critical; the manual error risk drops to zero, and operational coordination hits top speed.
The second concept is scaling under load and performance. The food and beverage ecosystem in the terminal generates serious momentary loads during peak passenger traffic hours; sales transactions and end-of-day reconciliations can get clogged under this load. That is why we moved the infrastructure to a simple, resilient services architecture where each component can be scaled individually. Separating the old monolithic structure into independently running components made it possible to expand only the heavily loaded part during peak hours; the entire system was saved from being affected by a single bottleneck. This approach was met with a performance leap of nearly 9 times in some of the applications we modernized, and its value was twofold: businesses' efficiency increased, and passenger wait times shortened, improving the experience.
How the Collaboration Began
ISG's need was a technology partner to modernize its critical systems without stopping them, and even build some from scratch. As Phexum, we joined this project by taking on all architectural and technology transformation, business analysis, product development from scratch, and subsequent maintenance and operation support. We started by deeply analyzing the airport's critical workflows; because in an environment of this sensitivity, every development decision required fully understanding the reality of the operation.
Building Blocks of the Solution
The project took shape in two main modules. The Flight Information Management Portal is a system we developed from scratch. This portal gathers raw flight data flowing from different sources into a central pool, gives operations personnel the ability to quickly verify and approve, and transfers the approved information in real-time to relevant screens and external systems. Role-based authorization, user management, and complete transaction history were also built as part of this portal. Modernizing Food and Beverage applications was a separate effort; we carried sales and end-of-day (Z report) data of commercial software in the terminal to central systems and SAP error-free, made the load manageable during peak hours, and re-approached performance. These two lanes rose on cleared technical debt and a high-performance infrastructure built from scratch. We made the impact of this modernization approach measurable. We compared the old and new versions of the data processing services we renewed in the same period under the exact same load. The results painted a clear picture: in conditions where the old version could only process ~70 records per second, the new architecture went over ~650 records per second. This means an acceleration of approximately 9 times on the record processing side and over 11 times on the update operations side under high load; moreover, this gain is maintained not just in heavy load but also in low-volume transactions.
From ~70 records per second to over 650 — a nearly 9x acceleration, without stopping a critical airport for a moment.
The Impact We Created
Sabiha Gökçen's digital infrastructure transformed from a structure carrying the burden of aging technology and at risk of clogging, into a modern ecosystem eliminating system interruptions and securing operational continuity. With the Flight Information Management Portal we built from scratch, we brought the manual error risk to zero, and with the modernized commercial applications, we accelerated the passenger experience. We achieved all this with a highly scalable and secure architecture without stopping a critical airport for even a moment.