Payments and Transaction Flows for Neobanks

Neobanks have redefined what modern banking looks like—instant onboarding, seamless payments, and 24/7 access to money management tools. But behind every “one-tap payment” or “instant transfer” is a complex, event-driven infrastructure that makes real-time financial experiences possible. 

At OceanoBe, we’ve worked with multiple neobanks and fintechs to design, build, and optimize payment architectures capable of processing thousands of transactions per second—securely, reliably, and in full compliance with regulations like PSD2 and AMLD5. 

Event-driven architectures, automation, and intelligent monitoring come together to support modern neobanking payment ecosystems. 

1. The Core of a Neobank: Real-Time Transaction Processing 

Unlike traditional banks that rely on batch settlement systems, neobanks must operate in real time. Every user action—from card swipes to wallet top-ups—triggers events that need to be validated, processed, and reconciled in milliseconds. 

How it works 

When a user initiates a payment:

A payment initiation event is created through APIs (often PSD2-compliant). 

The event is placed on an event bus (e.g., Kafka, RabbitMQ) and picked up by specialized services handling authorization, risk, and fraud checks. 

Once verified, a settlement service posts the transaction, and the ledger microservice updates balances in near real time. 

Simultaneously, the system emits monitoring and audit events for traceability and compliance logs. 

This asynchronous, event-driven flow ensures scalability and fault tolerance—core requirements for high-volume digital banking. 

2. Architectural Blueprint: From Initiation to Reconciliation 

At OceanoBe, our neobank architectures are typically composed of modular, domain-driven microservices orchestrated via message streams. A simplified architecture might include: 

• API Gateway – Manages external communication, handles authentication (OAuth2, JWT), and enforces rate limiting. 
• Payment Orchestration Layer – Routes payment requests through available rails (SEPA, SWIFT, FPS, cards, or local APMs). 
• Core Ledger Service – Maintains accurate balance records and supports double-entry accounting. 
• Fraud & Risk Engine – Uses AI-based pattern recognition to identify anomalies in transaction behavior. 
• Reconciliation Service – Matches outbound and inbound transactions daily, ensuring end-of-day financial accuracy. 
• Compliance & Reporting Module – Automates the generation of regulatory reports, e.g., AML, KYC events, or suspicious transaction logs. 

Each of these services communicates through a pub/sub event model, allowing horizontal scaling and asynchronous execution. 

By decoupling payment components, neobanks achieve resilience and flexibility—upgrading a fraud detection model or integrating a new payment rail without disrupting the core transaction flow. 

3. Automation: From Workflow to Compliance 

Automation sits at the center of operational excellence in neobanking. From CI/CD pipelines that deploy microservices, to bots that reconcile ledger mismatches, automation reduces human error and accelerates innovation. 

Key automation layers include: 

• Automated CI/CD Delivery: Infrastructure-as-Code (IaC) tools like Terraform and Ansible manage cloud environments, while CI/CD orchestrators (e.g., GitLab CI, Jenkins) push updates across multiple regions. 
• Automated Testing Pipelines: API, regression, and performance tests run before every deployment using frameworks such as RestAssured, Postman, and Karate. 
• Automated Reconciliation and Reporting: Scheduled jobs verify transaction data across systems, ensuring every debit equals a credit and discrepancies are flagged instantly. 
• Regulatory Automation: PSD2 audit logs, consent records, and anti-fraud alerts are automatically stored, versioned, and reported to compliance systems. 

By implementing event-based automation triggers, teams can move from reactive issue management to proactive quality assurance and compliance. 

4. Monitoring and Observability: Seeing Everything in Real Time 

A neobank’s architecture is only as reliable as its monitoring stack. 

When dealing with millions of microtransactions daily, issues must be identified and addressed before they reach the customer. 

Modern monitoring stack 

Centralized Logging: Tools like ELK (Elasticsearch, Logstash, Kibana) or Grafana Loki aggregate logs from distributed services. 

Real-Time Metrics: Prometheus scrapes latency, error rates, and throughput across payment services, offering live dashboards. 

Alerting Pipelines: Alerts are integrated with Slack, Teams, or PagerDuty, ensuring instant visibility. 

Transaction Tracing: Using OpenTelemetry or Jaeger to trace each transaction end-to-end across microservices for compliance and debugging. 

At OceanoBe, we integrate monitoring as a core architectural component—not an afterthought—because every anomaly can represent both a technical issue and a regulatory risk. 

5. Event-Driven Design: Resilience by Default 

Neobanks operate in unpredictable conditions—network spikes, API delays, third-party downtime. 

Event-driven architecture (EDA) ensures fault tolerance and graceful degradation in such cases. 

How EDA supports resilience 

Retry & Idempotency: Each event carries a unique ID, so if processing fails, the system retries without duplication. 

Decoupled Components: Payment initiation doesn’t wait for settlement confirmation—it continues asynchronously. 

Event Sourcing: The system stores immutable transaction logs, allowing reconstruction of any account state at any time (a major compliance advantage). 

With event-driven systems, neobanks can scale across geographies and handle complex multi-rail payment ecosystems with consistent performance and accuracy. 

6. Compliance and Audit Automation 

In regulated environments, auditability isn’t optional—it’s mandatory. 

Automation supports compliance by embedding traceability into every transaction. 

For instance: 

Every API call is logged with timestamps, IDs, and consent tokens (for GDPR and PSD2). 

Reports are auto-generated for AML teams, detailing transaction histories, thresholds, and anomaly detection summaries. 

Versioned deployment and configuration histories provide evidence during audits—showing when a rule was added, changed, or deprecated. 

By embedding compliance logic into the architecture, OceanoBe helps fintech clients achieve “continuous compliance”—aligning innovation with regulatory assurance. 

7. Partnering for Scalable Payment Systems 

Building and maintaining a multi-rail, compliant payment system isn’t just about technology—it’s about strategy. 

As a technical partner, OceanoBe collaborates with product owners, architects, and compliance officers to: 

• Modernize legacy transaction engines. 
• Design event-driven, microservice-based payment architectures. 
• Automate operational reporting and monitoring. 
• Integrate with regional payment networks (SEPA, FPS, Visa Direct, etc.). 

Our approach combines deep domain understanding with engineering excellence—bridging the gap between regulatory expectations and real-time innovation. 

Real-Time Is the New Normal 

The modern neobank’s ability to compete depends on how efficiently it moves money, ensures trust, and meets compliance—all in real time. 

Event-driven automation, observability, and modular architecture are no longer optional—they’re the foundation for future-ready financial platforms. 

At OceanoBe, we help neobanks and fintechs design resilient, high-performance payment systems that balance speed, compliance, and reliability—turning real-time financial experiences into everyday reality.