Olusola Ojewunmi

About Me

Engineering with intent

I build the systems that power products people depend on. Over five years of building in the trenches of production backend engineering, I've shipped 15+ APIs serving real users across fintech, healthcare, logistics, and hospitality.

My work lives at the intersection of domain complexity and engineering discipline — designing state machines, decomposing monoliths into microservices, and architecting event-driven systems that remain coherent under pressure.

I've been the sole engineer who ships, the team lead who unblocks, and the architect who thinks three steps ahead. Whether it's a multi-tenant SaaS platform, a government logistics system, or a healthcare payments engine — I take ownership of outcomes, not just tasks.

Years Experience

Production APIs

Industry Domains

Test Coverage Gains

Good backend engineering is invisible. Users never think about the API, the queue, or the state machine — they just trust the product.

Domains I've shipped in

Fintech HealthTech Logistics PropTech GovTech SaaS Alumni Tech HR Tech

Technical Skills

The stack behind the systems

Production-proven tools from API design to deployment infrastructure.

⚡

Backend & Languages

Core engineering stack

PHP Laravel Yii2 Symfony RESTful APIs gRPC Domain Modelling Event-Driven Arch State Machine Design

🗄

Databases & Storage

Data persistence layer

MySQL PostgreSQL MongoDB Redis SQLite Aggregation Pipelines Replica Sets

💳

Payments & Fintech

Financial systems

Paystack Stripe Braintree Remita Virtual Accounts Tokenized Mandates Ledger Reconciliation Dual-Ledger Wallets

🚀

DevOps & Infrastructure

Build & deploy pipeline

Docker GitHub Actions DigitalOcean Linode Linux/Ubuntu Laravel Octane Supervisor Laravel Pulse

📨

Queues & Messaging

Async & event systems

RabbitMQ Apache Kafka Laravel Horizon Supervisor Event Dispatching

🔬

Testing & Observability

Quality & monitoring

PHPUnit Pest TDD Paratest Honeybadger Sentry Datadog Telescope

Work History

Where I've built things

A track record of ownership, promotion, and shipping in fully remote, distributed teams.

Senior Backend Developer

Jan 2025 – Present

Squadio (Contract) · Client: ******* — Saudi Hospitality & PropTech · Remote

Designed and implemented the OTA integration layer end-to-end — hotel availability, room confirmation, dynamic pricing resolution, and concurrent unit orchestration via DTOs and service abstractions.
Architected the bulk offer and discount management system in the pricing microservice, including batch job processing, discount conflict validation, and offer group lifecycle management.
Built the performance insights dashboard backend using MongoDB aggregation pipelines with host-scoped authorization and reservation metrics.
Raised test coverage from ~5% to ~90% on key services by authoring comprehensive production test suites with DI patterns and MongoDB model isolation.
Developed a custom FeatBit PHP SDK for feature flagging across Laravel services, with automated CI via GitHub Actions.

Yii2 MongoDB gRPC Microservices PHPUnit Pest GrowthBook SDK

Engineering Team Lead

Dec 2020 – Present

NQB8 Limited · Product Studio — Promoted from Software Engineer · Remote

Send24 (Logistics): Architected entire logistics backend from initial commit — wallet-based payments, WhatsApp-integrated order creation, PDF invoice generation with Google Drive storage, and a role-based operations dashboard.
CLRD (GovTech): Designed a microservice-based government logistics regulation platform with RabbitMQ inter-service comms, CAC business verification, Remita payment integration, and QR-based vehicle/rider management.
Residifi (PropTech): Built a multi-tenant residential management system with Spatie Multitenancy, Livewire Volt interfaces, visitor access codes, and Excel-based resident import with eager loading.
Axocheck (HealthTech): Core feature development including Paystack/Stripe/Braintree integrations and professional payout scheduling.

Laravel PostgreSQL RabbitMQ Docker Livewire Spatie Multitenancy

Backend Developer

Apr 2023 – Apr 2025

Clafiya Limited · HealthTech · Remote

Engineered automated wallet top-up and recurring payment systems using tokenized mandates with direct debit, including rollback-safe HSA balance transfers across daily/weekly/monthly cycles.
Designed accruing spend limit enforcement for employer-sponsored Health Savings Accounts with sponsor-controlled toggles and monthly carryover logic.
Built a Symfony API gateway using API Platform, Doctrine ORM, and JWT authentication for secure third-party API key management.
Integrated Kafka-based event dispatching for consultation data sync, plus Typesense full-text search across 75+ models and 144 controllers.

Laravel Symfony Kafka Typesense Google Calendar API Mixpanel

🎓

Bachelor of Science — Computer Science

University of Ibadan

Feb 2016 – Feb 2020 · Ibadan, Nigeria

Freelance & Independent

Products I've owned

End-to-end platforms built from schema to deployment — sole engineer to production.

01 / 03

🏢

Venspace

Space Booking & Marketplace API

Multi-tenant space booking platform with custom domain support, DNS verification, and tenant-scoped data isolation — built for scalable marketplace operations.

State machine-driven booking lifecycle: initiated → confirmed → active → completed
Dual-ledger wallet with virtual accounts, gift cards & dispute resolution
KYC with BVN validation, PII hashing & per-tenant branding
POS module for walk-in bookings with guest user creation

Laravel Spatie Multitenancy Paystack Ably BunnyCDN Laravel Pulse

02 / 03

🔍

Laurel Checks

Employee Verification Platform

Multi-tenant employee background verification platform with Livewire-powered admin interfaces, RBAC enforcement, and asynchronous batch processing pipelines.

Async batch import with Excel parsing, chunk processing & row-level error tracking
Cloudinary file sync with checksum-based idempotent uploads
Downloadable PDF reports for guarantor/referee verification
SSH-based deployment automation with backup & env management

Laravel Livewire Spatie Permission Cloudinary DomPDF Maatwebsite Excel

03 / 03

🎓

Alma

Multi-Tenant Alumni Platform API

Full-featured alumni association platform supporting membership management, event organization, job postings, career advice, and social features with per-association data scoping.

Ledger-style financials with Paystack: payment intent tracking & audit tables
Event-driven subscription lifecycles with dues tracking & payment insights
RBAC across 90+ API endpoints via Spatie Permission
Auto-generated API docs via Scramble + Laravel Nightwatch observability

Laravel Spatie Multitenancy Paystack Cloudinary Scramble Laravel Nightwatch

Earlier builds

WriteRight

Sole Developer

Content verification platform built end-to-end — user authentication, email verification flows, and the complete API from schema design to deployment.

Laravel REST API Auth

Drop24

Sole Developer

Delivery and drop service API with wallet debit transactions, courier signup flows, and status-filtered request management — designed and shipped independently.

Laravel Wallet Courier Flows

Merchant Payment Gateway

Backend Developer

Implemented loan request functionality and merchant detail retrieval endpoints with tokenized user authentication for a payment processing platform.

PHP Tokenized Auth Payments

Numbers that tell the story

Measurable outcomes from production systems, across years of engineering ownership.

⚙️

Production APIs

Shipped across 6 domains

🧪

Test Coverage

Up from ~5% on key services

🏗️

Industry Domains

Fintech · Health · Logistics & more

🗂️

Years Remote

Distributed teams globally

Laravel ✦ Microservices ✦ Event-Driven Architecture ✦ Kafka ✦ Financial Engineering ✦ MongoDB ✦ TDD ✦ State Machines ✦ Multi-Tenancy ✦ Docker ✦ Laravel ✦ Microservices ✦ Event-Driven Architecture ✦ Kafka ✦ Financial Engineering

Engineering with intent

The stack behind the systems

Where I've built things

Products I've owned

Numbers that tell the story

Let's build something remarkable