Senior Backend Engineer · Abuja, Nigeria

I build the backend systems that move money.

10 years building financial systems at scale — payments, core banking, and identity. Currently at Moniepoint, building high-availability payment APIs on a platform that processes 100+ million transactions a day.

Get in touch See my work
Portrait of Moses Abubakar
100M+transactions a day on the payments platform I work on
50K+users on the OAuth2/SSO platform I designed
99.99%uptime on core banking for 4 microfinance banks
10 yrsbuilding production backend systems
Live estimate 0 transactions processed on Moniepoint since you opened this page at 100M+/day

How I think about payments

Retries happen. Double charges shouldn't.

Networks time out and clients retry. Without idempotency, a single airtime purchase can be billed twice. Every request carries an idempotency key; a retry with the same key replays the original result instead of charging again.

This pattern, together with transaction monitoring and retries, raised the airtime purchase success rate at Moniepoint by 18% and stopped double-billing.

01 About

I'm a backend engineer who has spent the last decade in fintech, where correctness, uptime, and security aren't optional. My work sits in the parts of the stack customers never see but always feel: payment pipelines, core banking ledgers, and the authentication layer that ties an organisation's services together.

At Moniepoint I build payment APIs and migrated 18B+ transaction rows from MySQL to Google Cloud Spanner. At VFD Group I designed a centralized OAuth2 & SSO platform used by 6+ companies and customized Apache Fineract as the core banking system for four microfinance banks.

I work mainly in Java (Spring Boot), Node.js (NestJS), Go, and Ruby on Rails, and I'm certified in Kubernetes (CKAD) and AWS. I've also led teams — introducing Agile practices and engineering standards that make delivery predictable.

02 Experience

  1. Senior Backend Engineer @ Moniepoint Inc

    Nov 2025 — Present
    • Design and maintain high-availability Java payment APIs on a platform processing 100M+ transactions daily.
    • Migrated 18B+ transaction rows (six months of history) from MySQL to Google Cloud Spanner for horizontal scalability.
    • Implemented duplicate-purchase detection and idempotency checks, with transaction monitoring and automatic retries — raising the airtime purchase success rate by 18% and eliminating double-billing.
    • Integrated 3 third-party airtime and data providers, launching new value-added services.
    • Built a recurring-purchase service so customers can schedule automatic airtime and data top-ups.
    JavaPaymentsCloud SpannerMySQLIdempotency

    Ships in the Moniepoint app: Google Play ↗ App Store ↗

  2. Senior Backend Engineer @ VFD Group

    Jan 2024 — Nov 2025
    • Designed and deployed a centralized OAuth2 Authorization & Resource Server with SSO in Java across 6+ group companies — 50,000+ users, 100+ internal APIs secured.
    • Supported Authorization Code, Client Credentials, and Refresh Token grants with multi-tenant isolation, scoped tokens, and <150 ms token issuance at peak.
    • Reduced redundant login flows by 60% and improved session consistency system-wide.
    • Customized Apache Fineract as the core banking platform for 4 microfinance banks — 100,000+ monthly transactions at 99.99% uptime.
    JavaOAuth2SSOMulti-tenancyApache FineractCore Banking

  3. Team Lead @ Outsource Global Technologies

    Jan 2022 — Jan 2024
    • Led a team of 8+ developers delivering a company-wide ERP — payroll, recruitment, attendance, leave management, and procurement — replacing manual processes and saving ₦40M annually.
    • Introduced Agile methodologies and engineering best practices, improving sprint delivery consistency by 30%.
    LeadershipAgileERP

  4. Senior Fullstack Developer @ DATHARM (Contract)

    Jan 2021 — Jan 2022
    • Modernized legacy Ruby on Rails systems onto a NestJS/React stack, improving performance by 40%.
    NestJSReactRuby on Rails

  5. Co-Founder & Fullstack Developer @ Console Dotlog Tech Solutions

    Jan 2016 — Jan 2021
    • Built backend systems in Java, Node.js, and Ruby on Rails with a 98% first-time QA pass rate.
    JavaNode.jsRuby on Rails

03 Projects

Moniepoint app icon

Fintech · Moniepoint Inc · 10M+ downloads

Moniepoint Personal Banking

Moniepoint's consumer banking app — instant transfers, cards, savings, and bill payments. I work on the payment APIs behind it, including airtime and data purchases, scheduled recurring top-ups, and the idempotency layer that prevents double-billing.

Get it onGoogle Play Download on theApp Store
100M+transactions processed daily
+18%more airtime purchases completing successfully
18B+rows migrated to Cloud Spanner
Bvndle app icon

Loyalty as a Service · PSL

Bvndle

A loyalty platform I worked on as one of the backend developers, built for PSL and used by UBA and MTN Nigeria to reward staff and customers based on target achievements. Today it's a consumer rewards app where users earn BvndleCoins on everyday spending and redeem them for data, airtime, and marketplace items.

Get it onGoogle Play Download on theApp Store
UBA · MTNenterprise clients rewarding staff & customers
SSOsecured as a resource server on the OAuth2 platform I designed
ERP dashboard screenshot

Outsource Global Technologies

Enterprise ERP

Company-wide platform covering payroll generation, recruitment, attendance monitoring, leave management, and procurement.

FindThatPlug screenshot

e-Commerce · Product lead

FindThatPlug

Location-based product discovery app that finds the product nearest to a customer.

Identity · VFD Group

OAuth2 & SSO Platform

In production at VFD Group for secure single sign-on across group companies, with Bvndle as a resource server.

Wealth management

IWealth

Financial management systems tracking assets and liabilities for Norrenberger Investment Company.

Estate management

Nesta

Secure resident access control, visitor management, and automated utility billing modules.

04 Skills

Java

Spring Boot · JPA/Hibernate · JUnit · Mockito · Concurrency & multithreading

Node.js

NestJS · TypeORM · Prisma · Jest · Supertest · Swagger

Go

SQLC · Goroutines · Table-driven tests

Ruby

Ruby on Rails · Active Record · Sidekiq · RSpec · FactoryBot · Devise · Pundit

Security

OAuth2 · SSO · JWT · RBAC · Encryption · Hashing

Cloud & DevOps

AWS · Kubernetes · Docker · Linux · CI/CD (GitHub Actions, Jenkins) · CNCF ecosystem

Databases

PostgreSQL · MySQL · Cloud Spanner · MongoDB · Redis

Architecture & Messaging

Microservices · Hexagonal architecture · SOLID · gRPC · Protobuf · Kafka · RabbitMQ

CKAD

Certified Kubernetes Application Developer

The Linux Foundation

AWS

AWS Certified Cloud Practitioner (CLF-C02)

Amazon Web Services

B.Eng

Metallurgical & Materials Engineering

Ahmadu Bello University, Zaria · 2009 — 2014

Let's build something reliable.

Open to remote senior backend and platform roles, consulting on payments and identity systems, and good conversations about distributed systems.

dev.mosesabubakar@gmail.com