BUILDING SECURE AND SCALABLE FINTECH ECOSYSTEMS WITH APIS AND MICROSERVICES

Awogbade Kehinde; Omisope Abiodun Oluwasegun; Asiyanbola Olaoluwa Ebenezer; Samson Precious Loveth; Iyiola Ifeoluwa Johnson

doi:10.5281/zenodo.21501486

Abstract

The fast growth of financial technology (FinTech) has transformed the way financial services are being delivered, from monolithic financial institutions to agile, interconnected digital ecosystems that are based on application programming interfaces (APIs) and microservices architectures. This paper provides a thorough survey of the principles, patterns and issues in FinTech ecosystem design, with the goal of making the ecosystems secure, scalable, and compliant to ever-changing regulatory demands. The study draws from peer-reviewed literature from the past seven years (2017 to 2024), industry best practices and technical frameworks to explore how API gateway design, OAuth 2.0/OpenID Connect (OIDC) authentication, service mesh patterns, event-driven communication, container orchestration with Kubernetes and zero trust security models facilitate a strong FinTech platform architecture. The review also examines regulatory compliance aspects such as PCI-DSS, PSD2 (Open Banking) and GDPR and how these are catered for in microservices-based designs. Results show that architectural choices at the API boundary such as versioning, rate limiting, mutual TLS enforcement and granular authorization scoping can have disproportionate impact on the security and scalability posture at the overall ecosystem level. The paper concludes with a look at the trends that are emerging on the FinTech security horizon, such as AI-powered anomaly detection, decentralized identity, and confidential computing.

Keywords

FinTech; API Security; Microservices Architecture; Open Banking; PSD2; OAuth 2.0; Zero-Trust Security; Kubernetes; Service Mesh; PCI-DSS; Scalability; Event-Driven Architecture

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