Kosi Kaira Onyia

Kosi Kaira Onyia

I build software and spend a lot of time wondering why things are the way they are. An introvert with a soft spot for animals, a head full of questions, and a heart very much taken.
Welcome to my little corner of the internet. A personal playground inspired by seyi.wtf, built for my wandering thoughts, occasional experiments, and everything in between.

Software Engineer. Endlessly curious. コシ・カイラ・オニア

LAGOS · --:-- 

Kosi Kaira Onyia

Resume

Backend engineer · Python & FastAPI · Lagos, Nigeria

Profile

Backend engineer in Lagos who builds APIs with Python and FastAPI. I care most about the parts that are easy to get wrong: bookings that can’t be oversold when two people grab the last slot at once, payment webhooks that are safe to receive twice, and live updates that reach people the moment something changes. I work mainly with FastAPI, PostgreSQL, Redis and SQLModel, test the tricky paths with Pytest, and I’m currently building a product that matches CVs to jobs and keeps applications in one place.

Projects

WashWagon ↗

Team project

Backend for a laundry pickup and delivery service. Pickup slots are capacity-controlled and stay correct even when several customers try to book the last space at the same time. Payments run through Paystack with signed webhook verification and idempotent handling of duplicate events, and order-stage changes reach customers live through Redis Pub/Sub and Server-Sent Events. Customers, couriers and operations managers each get role-based access, backed by an automated Pytest suite.

Python, FastAPI, PostgreSQL, Alembic, Redis Pub/Sub, Paystack, JWT, Pytest

Backend for a weekly rotating savings circle (ajo/esusu): members contribute a fixed amount each week and one member collects the pot by turn. Contributions only count once a trusted bank service confirms the transfer has cleared; confirmation is idempotent and writes an audit ledger entry in a background task. JWT authentication with bcrypt-hashed passwords, plus a separate API-key route for the bank.

Python, FastAPI, SQLModel, SQLite, JWT, bcrypt

LagosRoute ↗

Personal project

A read-only API for exploring Lagos transport routes, stops, fares and fleet information from a structured sample dataset, with parameter validation, pagination, filtering and consistent JSON responses.

Python, FastAPI, REST API

Task Management API ↗

Personal project

A task-management API with user-linked tasks, API-key protected routes, status changes and pagination. Completing a task logs it to a report in a FastAPI background task.

Python, FastAPI, SQLModel, SQLite

Skills

Languages
Python, SQL, TypeScript
Backend
FastAPI, Pydantic, SQLModel, REST APIs, JWT auth, Webhooks, Server-Sent Events, Background tasks
Data
PostgreSQL, SQLite, Alembic, Redis
Tools
Pytest, uv, Git, GitHub
Frontend
React, Next.js, CSS

Contact

onyiakosisochi@gmail.com · github.com/kosionyia · linkedin.com/in/kosionyia