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Executive Summary
A top-tier bank with a strong presence in Central and Eastern Europe (CEE) partnered with mindit.io to improve the performance and responsiveness of its digital self-care channels. With over 14 million customers and vast volumes of transactional data to process, the bank needed a robust solution to support real-time search and aggregation for mobile and web banking applications.
mindit.io delivered a high-performance API built on Cassandra, Java, and REST, enabling seamless access to transaction history across terabytes of data. The result was a significant boost in speed, scalability, and customer satisfaction across digital channels.
Key Results:
- Real-time API deployed for mobile and web platforms
- Terabyte-scale transaction datasets indexed and searchable
- High throughput and low latency achieved in production
- Improved digital experience for millions of banking customers
About the client
Our client is a leading financial institution with one of the largest footprints in the Central and Eastern European region. With a workforce exceeding 45,000 professionals and over 14 million customers, the bank is committed to innovation and digital-first services that empower customers to manage their accounts independently.
As demand for responsive digital banking increased, the client sought to enhance its self-care experience through real-time access to transaction data, improving transparency and customer satisfaction.
The Challenge
With terabytes of historical and real-time transaction data, the bank needed an API that could:
- Search across massive datasets without compromising performance
- Deliver results with low latency and high throughput
- Scale across both web and mobile self-care channels
- Integrate securely within existing digital banking infrastructure
The technical complexity was amplified by the need to evaluate multiple approaches for indexing and serving data efficiently, as well as designing a REST endpoint capable of meeting demanding performance expectations.
Project Goals
The project was centered on enabling fast, scalable, and secure access to customer transactions across mobile and web channels. mindit.io was engaged to:
- Evaluate and select the optimal indexing strategy for large-scale transactional data
- Implement a high-performance REST API backed by a distributed architecture
- Ensure rapid response times and consistent uptime
- Deliver a solution that would elevate the customer self-care experience while maintaining enterprise-grade security
Our Solution
mindit.io designed and implemented a real-time transaction search API using a powerful stack composed of Cassandra, Java, and REST. Key elements of the solution included:
- Scalable Data Architecture: Leveraged Cassandra to handle high-velocity read operations and distribute data across nodes
- Optimized Query Layer: Designed and tested multiple indexing strategies to achieve the best trade-off between performance and flexibility
- REST API Implementation: Developed lightweight endpoints optimized for fast response times and secure communication
- Performance Tuning: Benchmarked query latency and throughput to meet strict performance thresholds
This architecture allowed mobile and web self-care channels to deliver seamless, near-instant transaction search results to customers.
Implementation Process
The implementation followed an agile and collaborative approach:
- Requirement Discovery: Worked with the client’s digital banking and infrastructure teams to define functional and performance needs
- Technology Evaluation: Assessed various indexing techniques and data models suitable for terabyte-scale workloads
- API Design and Development: Built the REST API with a strong focus on efficiency and scalability
- Testing and Validation: Conducted intensive QA cycles to ensure stability and rapid response under real-world conditions
- Deployment and Monitoring: Deployed the solution to production with real-time monitoring and performance tracking in place
Results
The API went live with immediate impact across the client’s self-care channels:
- Real-Time Access: Customers gained instant access to historical and live transaction data
- Improved User Experience: Reduced wait times across mobile and web applications
- Scalable Design: Built to accommodate growing data volumes and peak user activity
- Secure Integration: Compliant with the bank’s stringent data protection and security protocols
Client Testimonial
“This API was a major step forward in improving our digital channels. The mindit.io team understood the complexity of our data and delivered a fast, secure, and reliable solution that scaled with our needs.”
— Digital Banking Lead, CEE Region
Visuals and Supporting Media
To help internal teams and stakeholders visualize the implementation, mindit.io provided:
- API Architecture Diagram: Detailed illustration of data flow from Cassandra to web and mobile channels
- Performance Benchmark Graphs: Showcased key latency and throughput metrics
- Security Overview: Documented encryption, access control, and compliance layers
- UX Impact Snapshots: Demonstrated improved search times in real self-care interfaces
Strategic Takeaways
This project highlights the strategic value of building real-time capabilities for digital banking platforms:
- Data Volume is No Longer a Barrier: With the right architecture, even terabytes of data can be served in real time
- Performance Drives Satisfaction: Faster access to information means better experiences for end users
- Scalability is Essential: Systems must handle future growth without compromising performance
- Security Cannot Be an Afterthought: Real-time access to sensitive financial data requires robust protection
- API-First Design Wins: Modular, scalable APIs are the foundation of modern digital banking ecosystems
What’s next?
Looking to improve your digital self-service experience or unlock real-time access to critical data?
Let’s talk about how mindit.io can help you build high-performance, secure APIs for your banking platforms.
