Available for opportunities

Full Stack
Engineer who
thinks in money flows

I build production-grade financial systems — double-entry ledgers, FX platforms, cross-border payment engines. 2+ years shipping at Access Bank Africa and beyond.

7+
Projects shipped
4.85
Fintech assessment score
0
Double-spends in production
14
Blockchain networks integrated
Mayopo Adeoye

About me

Engineer who operates at the intersection of code and capital

I'm a Full Stack Engineer based in Lagos, Nigeria, specialising in financial systems, payment infrastructure, and real-time applications. My background in Mathematics sharpens how I think about correctness, edge cases, and failure modes.

At Access Bank Africa, I built the RetailFX Solution — handling trade bookings, bulk approvals, Nostro GL debits, and CRON-based reconciliation for one of Africa's largest banks. That experience gave me a deep appreciation for systems where bugs have real financial consequences.

I approach every project with the same question: what happens when this fails? Then I build accordingly.

Fintech Engineering Assessment — 4.85 / 5.00

Independently assessed by TJOC LLC payments team. Rated Strong Hire. Exceptional marks on concurrency, schema design, webhook handling, and failure scenario analysis.

Triple-layer concurrency control

Advisory locks + SELECT FOR UPDATE + SERIALIZABLE isolation with deterministic lock ordering. Zero double-spends.

Production financial systems

Double-entry bookkeeping, HMAC webhook verification, idempotency pipelines, FX quote lifecycle, and ledger integrity constraints.

Full stack across the board

Node.js, Java/Spring Boot, React, NestJS, PostgreSQL, OracleDB, Docker — whatever the system needs.

Core capabilities

What I bring to your team

💳

Payments & Fintech

Double-entry ledgerFX systemsIdempotencyHMAC webhooksStripePaystackCross-border payments
⚙️

Backend Engineering

Node.jsPostgreSQLJava / Spring BootNestJSOracleDBRedisREST APIs
⚛️

Frontend

React 18Redux ToolkitTypeScriptTailwind CSSMaterial UIQuasarSocket.IO
🔒

Security & Reliability

SERIALIZABLE isolationJWT / RBACSpring SecurityActive DirectoryOWASP
🔗

Blockchain & Web3

DEX / Cross-chainSolidityBIP-39Supabase Edge FunctionsSmart Contracts
🚀

Infrastructure

Docker / PodmanGitHub ActionsNetlifyRenderPrometheusOpenAPI

Work history

Where I've shipped

2023
Aristack Solutions
Access Bank Africa

Software Engineer — RetailFX Solution

Led implementation of a trading platform for one of Africa's largest banks. Built trade booking with multi-stage validations, bulk upload and approval flows, Active Directory authentication, Hold and Release via amount block numbers on traded accounts, Nostro/FRO GL debits, CRON-based reconciliation, and trade reversal logic. Integrated FlexCube file generation, Entrust SSL, and real-time FX quote fetching via WebSocket.

ReactTypeScriptNode.jsOracleDBJavaCalypsoActive Directory
2025
Treasury System
Collaboration

Software Engineer — Enterprise Treasury Management

Collaborated on an enterprise TMS supporting core trading, asset management, and internal financial controls. Built backend services with Java 21 and Spring Boot 3, implemented Flowable BPMN for multi-stage approval workflows, real-time WebSocket notifications via STOMP/SockJS, and end-of-day batch settlement jobs. Built financial dashboards with ApexCharts, ECharts, and GoJS workflow visualisers.

Java 21Spring Boot 3Flowable BPMNOracle DBReact 18Redux ToolkitWebSockets
2025
iBloom
Full Stack

Software Developer — Chair Rental Platform

Built and deployed iBloom, a full-featured web application for a chair rental company covering bookings, logistics, admin operations, and customer engagement. Engineered a Node.js + Express backend with secure email-based authentication and Cloudinary image management. Integrated Redux Toolkit for global state and Socket.IO for real-time admin chat.

Node.jsExpressRedux ToolkitTailwind CSSSocket.IOCloudinaryNodemailer
2025
Chronos
Full Stack

Software Developer — Order Management System

Built a dynamic multi-product order creation platform with real-time validation and confirmation flows. Developed a scalable RESTful API with NestJS connected to PostgreSQL. Integrated Nodemailer for transactional emails and Twilio for SMS notifications. Designed a mobile-first UI with Quasar. Delivered a full handover package including GitLab repos, Render deployment, Postman collection, YouTube walkthrough, and a 2-page technical decision memo.

NestJSTypeScriptPostgreSQLQuasarCapacitorTwilioNodemailer
2024
Scholist
Full Stack

Full Stack Developer — Scholarship Discovery Platform

Led development of a university scholarship platform with custom web scraper increasing the database by 50% and reducing student search time by 35%. Built advanced filtering by GPA, major, citizenship, and location. Integrated Stripe payment processing for coach bookings and Socket.io real-time messaging.

ReactNode.jsMongoDBReduxSocket.ioStripeCheerio

Selected projects

Things I've built

01 — Featured
⭐ 4.85 / 5.00 · Strong Hire

PayRoute — Cross-Border Payment Engine

Production-grade payment processor with triple-layer concurrency control, double-entry bookkeeping, FX quote lifecycle management, HMAC webhook verification, and full idempotency pipeline. Independently assessed by a fintech payments team.

Node.js PostgreSQL React 18 Docker
GitHub →
02
⚠ Currently unavailable

RelaySwap DEX

Decentralized exchange frontend supporting token swaps and cross-chain bridging across 14 blockchain networks. Live price feeds via CoinGecko, BIP-39 wallet validation, custom swap widget with slippage controls, and Supabase Edge Function transaction logging.

React 18SupabaseCoinGecko APINetlify
relayswap.link
03

Access Bank RetailFX

Enterprise FX trading platform for Access Bank Africa. Trade booking, bulk approvals, Active Directory authentication, Nostro GL debits, Hold and Release via amount block numbers, CRON reconciliation, and FlexCube integration.

ReactTypeScriptOracleDBJava
Enterprise project
04

iBloom — Chair Rental Platform

Full-featured web application for a chair rental company covering bookings, logistics, admin operations, and customer engagement. Node.js + Express backend with real-time admin chat via Socket.IO and Cloudinary image management.

Node.jsExpressSocket.IOCloudinaryTailwind CSS
ibloomrentals.com →
05

Scholist Scholarship Platform

University scholarship discovery platform with custom web scraper increasing database by 50%. Advanced filtering by GPA, major, and citizenship. Stripe payment integration for coach bookings and Socket.io real-time messaging.

ReactNode.jsMongoDBStripeSocket.io
scholistapp.com →
06 — Open Source (Coming Soon)

Gmail Bulk Cleaner CLI

Built out of personal frustration when Gmail froze at 10,000+ unread emails — the UI only allows 50 deletions at a time. A Node.js CLI tool connecting to the Gmail API to bulk-delete emails based on filters, completely bypassing the UI restriction.

Node.jsGmail APICLIOpen Source
  • Bulk delete beyond the 50-email UI limit
  • Target by category: Promotions, Social, Updates
  • Filter by time range & operation logging
  • Interactive CLI prompts for safe execution
🔒 Private repo · open source coming soon

Get in touch

Let's build something that matters

I'm open to full-time roles, contract work, and interesting fintech problems. Based in Lagos — available remotely worldwide.

adeoyemayopoelijah@gmail.com ⤓ View / Download CV
Independent assessment result
4.85/5.00
TJOC LLC Fintech Engineering Assessment · 2025
Strong Hire Recommendation