CMR System (Union Bank of Nigeria)
Enterprise customer management, data consolidation, and operational reporting platform for core banking
Problem
Union Bank operated with customer data deeply fragmented across multiple siloed legacy systems—System A held account demographics, System B tracked transaction histories, and System C stored credit profiles. Operations teams and bank tellers wasted hours manually cross-referencing and consolidating data across disjointed terminal screens, creating high operational overhead, delayed customer service, and error-prone manual reporting.
Solution
Architected and developed a unified enterprise web platform and high-speed API aggregation layer using Java and Spring Boot. The system securely connects to disparate legacy core banking databases, transforms data into unified customer profiles, and caches high-frequency queries in PostgreSQL to serve instant operational dashboards and automated regulatory reports.
How It Was Built (Architecture & Implementation)
Core Banking API Gateway (Spring Boot & Java)
Designed secure RESTful API endpoints that orchestrate concurrent connections to legacy core banking infrastructure. The gateway retrieves raw data from Systems A, B, and C, normalizes complex proprietary data structures, and serves clean, structured JSON to internal client applications. Wrote comprehensive OpenAPI/Swagger documentation for cross-departmental adoption.
High-Performance Caching Layer (PostgreSQL)
Designed an intelligent, multi-tiered caching schema in PostgreSQL to store frequently accessed customer profiles and transaction summaries. This architecture dramatically decoupled read-traffic from brittle legacy mainframes, ensuring reports execute almost instantaneously without impacting core banking availability.
Enterprise Security & RBAC (JWT + Spring Security)
Implemented stateless JWT authentication and strict Role-Based Access Control (RBAC) governed by least-privilege principles. Frontline tellers access basic account details, while branch managers and risk auditors unlock full credit histories and audit trails.
DevOps & Infrastructure-as-Code (Docker, Jenkins, Terraform)
Containerized the entire microservice ecosystem using Docker for consistent multi-environment deployments. Built Jenkins CI/CD pipelines for automated regression testing and deployment, and authored declarative Terraform scripts to provision and manage cloud servers, database clusters, and secure networking.
Production Observability (Prometheus & ELK Stack)
Embedded Prometheus metrics instrumentation across all API routes to track real-time query latencies, throughput, and database connection pool health. Deployed an ELK Stack (Elasticsearch, Logstash, Kibana) pipeline for centralized distributed logging and proactive error alerting.
How I Improved It Over Time (Evolution & Iteration)
[ V1 (Legacy Connectivity Gateway) ]
Launched the initial synchronous API aggregation layer connecting directly to legacy mainframe systems. While successfully unifying customer data on a single dashboard, heavy multi-system joins caused query latencies to exceed 10+ seconds.
[ V2 (Intelligent Caching & Query Optimization) ]
Engineered and deployed the PostgreSQL intermediate caching and indexing layer. Query response times plummeted from >10 seconds down to sub-second (<800ms) execution, reducing load on core banking mainframes by over 70%.
[ V3 (Granular RBAC & Audit Compliance) ]
Upgraded the security architecture from broad employee access to strict, role-differentiated views. Tellers, supervisors, and compliance officers now interact with tailored UI permissions, ensuring strict adherence to Nigerian banking data privacy regulations.
[ Post-Launch Observability Rollout ]
Initial deployments lacked visibility into intermittent legacy network timeouts. Added complete Prometheus and ELK telemetry, turning blind spots into proactive alerts that ops teams intercept before employees report slowdowns.
Outcome & Business Impact
Approved, adopted, and deployed organization-wide across Union Bank operations. Successfully presented the system architecture, security rigor, and quantitative business impact directly to executive leadership (CIO and CTO). Proved enterprise-grade delivery capability across high-security banking infrastructure, legacy systems integration, and full DevOps lifecycle mastery.
My Role & Execution
Java Backend & DevOps Engineer. Designed and developed the Spring Boot RESTful APIs, engineered the PostgreSQL caching schema, implemented JWT/RBAC security, built the Jenkins CI/CD pipelines, wrote Terraform IaC definitions, and configured Prometheus/ELK observability.
Key Learnings
- Navigating enterprise banking security standards, data encryption, and strict regulatory compliance
- Architecting high-concurrency caching layers to shield fragile legacy mainframe banking systems
- Implementing end-to-end DevOps automation (Jenkins, Docker, Terraform) and observability (Prometheus/ELK)
- Executive technical communication and translating architectural decisions into measurable ROI for C-suite leadership