MoMo – Banking Integration
Host-to-Host APIs with over 30 Banks
Project Overview
MoMo is Vietnam's leading digital wallet. This project involved designing and deploying direct host-to-host API connections with over 30 partner banks, replacing intermediary systems (NAPAS) to enable real-time, zero-latency deposits and withdrawals while ensuring strict compliance with domestic eKYC and AML regulations.
My role
As Product Manager for Banking Integration, I led the technical solution design and coordinated with engineering, legal, compliance, and banking partners. I managed API contract negotiations, designed secure data flows (tokenization, payload encryption), and deployed a real-time reconciliation monitoring dashboard.
The Intermediary Bottleneck
As Vietnam's top digital wallet, MoMo serves millions of daily active users. However, early on, topping up e-wallets was done primarily via NAPAS or Internet Banking. This created significant friction: users had to log into separate platforms or re-enter card info, leading to a disrupted user experience. Furthermore, indirect connections carried compliance risks (eKYC and AML) and left MoMo vulnerable to high operating costs and sluggish incident resolution.
In a multi-party project, designing a solution that balances business objectives, technical requirements, and legal compliance demands a deep understanding of each party's limitations.
Project Lifecycle
Discovery
- Compliance Review
- Dependency Analysis
Definition
- Solution Design
- API Contracts
Execution
- Scrum Integration
- UAT & Security
Launch
- Pilot Deployment
- Real-time Monitoring
Iteration
- Error Handling
- Success Metrics
Company Objectives & API Architecture
To address the identified challenges, MoMo set a strategic objective to build a large-scale bank-connected platform. The goal was to reduce reliance on intermediary systems, proactively manage cash flow, improve data reliability, and optimize operating costs.
I aligned this vision with our product strategy, leading the design of a Host-to-Host API architecture connecting MoMo directly with the core banking systems of partner banks. This architecture enabled real-time deposit and withdrawal flows directly within the app, laying a solid, scalable foundation for future value-added financial services such as consumer credit, savings, and investments.
Compliance & Security By Design
A critical constraint was ensuring the solution complied with stringent Vietnamese banking regulations, specifically Circular 23/2019/TT-NHNN for account verification, Decree 117/2018/NĐ-CP for data security, and AML/FATF standards.
I translated these complex legal requirements directly into our technical workflows. We enforced mandatory KYC (account verification) when users linked their bank accounts, preventing any transactions until verification was successful.
Building a Bank-Grade API
Working directly with the engineering and security teams, I helped design a comprehensive security layer for the host-to-host API to prevent data leaks and request forgery.
Data Integrity
Implemented API communication over TLS and added payload encryption for all sensitive data (e.g., account info, transaction numbers).
Authentication
Designed a token-based authentication system combined with message signatures to ensure the authenticity of each request and prevent replay attacks.
Execution & Operations Management
Integrating with 30+ banks required a highly structured rollout. I divided the project into smaller phases: Pilot connection with the first bank, followed by gradual expansion, and finalization of the reconciliation monitoring system.
Scrum & Contract Negotiation
During technical development (API client, backend, reconciliation), I applied the Scrum framework with clear sprint objectives. For external dependencies (API contracts and compliance sign-offs), I coordinated linear timelines directly with partner banks to ensure on-schedule delivery.
Pilot & Real-Time Monitoring
During the pilot phase, we discovered data discrepancies (timestamp mismatches) between MoMo and the bank. I organized an emergency meeting, analyzed the root cause within 24 hours, and updated the API contract to prevent recurrence. We deployed a real-time dashboard to monitor invalid tokens, timeouts, and reconciliation discrepancies.
Results & Strategic Impact
The project successfully established direct host-to-host connections, enabling real-time deposits and withdrawals without users exiting the app. This drastically improved UX and established the foundational technical capability for MoMo's future value-added services.