LAGOS, NIGERIA · 6.52° N, 3.38° E

AI and backend engineer. I build the system around the model.

Four years of production systems for HR, fintech, edtech and government.

// I build things because I can't help it.

ApproveHR · the assistant's query engine

Ask it about someone's salary. It depends who's asking.

The model never decides who may see what. On every request it's handed only the fields the asking person is allowed to see, and protected ones arrive redacted.

Ask as:

“How much does Ada earn?”

What the model is given

What it answers

An illustration with made-up people. The real catalogue is built from the asker's own permissions, per request, before the model sees anything.

47tests on the engine
2token budgets per org: daily and monthly
4trace levels, because traces hold pay data

Also in production: a public-holiday engine that works out Nigeria's holidays from their rules and checks the news for the Federal Government's Eid declaration.

In review: a fairness check for performance ratings that hides groups under five, so no one person's score can be worked out, and AI review notes written with names taken out before the prompt.

Kowane · text-to-SQL evals

A query can run, return a number, and still be wrong.

Kowane answers a microfinance bank's questions in SQL. The hard part is knowing when it's wrong, so I built evals that send real questions through the real agent and score what comes back.

// The join was very confident. Confidence isn't a test.

A case from the suite:

The tempting answer

What passes

34cases through the real agent
14categories, incl. refusal and safety
resultsare compared, not SQL text

And it runs on purpose: repeat runs to catch flaky answers, a baseline that fails the run on any regression, and a workflow to trigger before a prompt change or a model upgrade.

EDMS · lead backend developer

Every action leaves a link in a chain you can check.

Document management for enterprise and government. Each audit entry carries the hash of the one before, so a quiet edit breaks the chain.

✓ chain verified

An illustration. The real trail is append-only, with a verify endpoint and export.

75endpoints under role-based access
6roles, with confidentiality tiers
~4klines in the circulars module, on BullMQ

And the AI part: scanned documents go through OCR, then Gemini writes a summary, behind a provider interface that can be swapped.

Android · debugging

My app's alarms kept vanishing. The phone was deleting them.

No crash, no error. The answer was one line, under a log tag I didn't write.

20:00:00.112 ScheduleReceiver run: next alarm 21:00 20:00:00.231 ScheduleReceiver alarm set 20:00:05.004 Hiber/hiber proxy alarm (uid=…, pkgName=com.tolu.dpc) 21:00:00.000 …………………………………… (nothing)

Reconstructed log. The Hiber line is the real one.

Range

Where I've shipped.

AI and backend are the spine. Tap a name to see the work.

// Ask me about any tile.

ProductRole

HR · fintech · edtech · government · hospitality · trading

Also built

One line each.

Schull LMS

Sole backend from the first commit: courses, quizzes, certificates and Paystack checkout, with signature-verified webhooks.

in production · AWS
Spotlight Creative Hub

Bookings, event tickets and food orders. One Paystack webhook, verified and idempotent, settles all four. Live

Django
Trade Height Sweden

Bilingual site with live metal and diamond prices cached in Redis, and a blog editor. Live

React · Express
Safescrow

Full-stack escrow: a six-state lifecycle, a wallet ledger, and a Paystack webhook that checks signature and source IP.

FastAPI · React
Scene Rec

Type a line, find the films where it's spoken, across 7,656 films. Next: embeddings, measured against the lexical baseline. GitHub

NLP
ChunkIt

Telegram bot that splits big files without recompressing them. Built because I couldn't send my uncle a video. GitHub

live · real users

Writing

Three I wrote up properly.

Experience

Where I've been.

Sep 2025 – now
Schulltech · Software Engineer

AI and backend across ApproveHR, EDMS and Schull LMS.

2025 – 2026
Freelance · Sole developer

Spotlight Creative Hub and Trade Height Sweden, both live.

Apr 2024 – Aug 2025
Safeboxx · Software Engineer

Automated savings billing on Celery and Redis, 500+ transactions a month. What the founder said ↓

Jan – May 2024
JIA Outdoor Services · Contract

A Django marketplace API for billboard advertisers, load-tested with Locust.

2023
HNG IX · Backend finalist

Top 1% of 22,000+.

About

I'm Tolu.

I genuinely enjoy the craft. I think in systems, and I ask uncomfortable questions about why something is built the way it is.

I want to build where being wrong costs something: finance, health, anything regulated. That's where you can't ship and see.

This year, outside the IDE

  • Revamping Àṣàrò, a reading app my friends and I use to quietly judge each other's progress. They didn't ask, but they'll thank me.
  • Pushing AI agents to see what breaks first when a new model drops.
  • Trying to gain weight. It's going. Slowly.
  • Going outside more.

People I've worked with

What they said.

We worked well together, so I will definitely refer you when someone next asks me for a backend guy.

Stanley OnwukaCTO, The Noti Company

This blew my mind. You've done an excellent job. I don't know what I was expecting, but I wasn't expecting this at all.

Chukwuemeka AwereFounder, Safeboxx

You did this?! This is incredible work.

Contact

Let's build something. Or just talk.

Full-time roles, contracts, or an interesting problem.