Open to full-time · contract · consulting

McdavidEmereuwa.

or, to my little cousins, Uncle Jabs.

I build systems where money can't go missing: payments, double-entry ledgers and fiscal compliance, from the Go service down to the Kubernetes cluster it runs on.

Hire me See the work

STATEMENTNo. UJ-2017

Mcdavid Jabuikem Emereuwa

Engineering Lead · Lagos, Nigeria

Books opened: Aug 2017
Years posted: 9
Domains: Pay · Tax · Health · ERP
Shipped for: NG · US · DE
Stack: Go · TS · Python · k8s
Webhook double-credits: 0.00
Plantain consumed: ∞

STATUS OPEN TO WORK

Thank you for reading the books.

Account 01 · Experience

The general ledger

Every role, posted in order with the newest first. The books opened at Andela in 2017 and haven't stopped balancing since.

Ref	Period	Account	Entry
JRN-010	Oct 2025 — now	TAX Fiscal compliance	Engineering Lead @ Westmetro · LagosLead on a live FIRS/NRS e-invoicing platform. Go services on Kubernetes turning ERP payloads into UBL e-invoices for IRN issuance.
JRN-009	Feb 2026 — Jul 2026	PAY Payments	Senior Software Engineer, Payments @ GradientFi · CentryOS · RemoteShopify and BigCommerce payment integrations, idempotent webhook ingestion, and dispute and chargeback reporting.
JRN-008	May 2022 — Dec 2025	ERP ERP & SMEs	Senior Software Consultant @ Oyasync Inc. · LagosHeaded engineering. White-labelled ERPNext into three SME products; the hospitality module runs at 18+ firms.
JRN-007	2020 — 2022 · 2023 — 2025	HLTH Health interop	Senior Software Engineer @ Parallelscore · New YorkFHIR/HL7 interoperability for ERPNext via OpenHIM and DHIS2, telemedicine, and video APIs for soccer match analysis.
JRN-006	May 2022 — Oct 2022	ECOM Commerce data	Senior Backend Engineer @ Emax Digital GmbH · MunichAmazon Marketplace connectors. Replaced an in-house crawler with Rainforest API and cut scheduler memory 4×.
JRN-005	Nov 2019 — Dec 2020	FNDR Founder	Backend Engineer & Co-founder @ Echovon · LagosAPIs that put physical retail stores online. Kafka-based on-prem ↔ cloud sync. Reached the Y Combinator 2020 interview stage.
JRN-004	Jan 2020 — May 2020	ENG Engineering	Lead Backend Engineer @ Roqables · LagosContract backend lead.
JRN-003	Nov 2018 — May 2019	ENG Engineering	Backend Engineer @ Fluidangle · Houston · RemoteBackend engineering for a US team.
JRN-002	Apr 2018 — Jul 2018	ENG Engineering	Frontend Developer @ Nairabox · LagosFrontend engineering.
JRN-001	Aug 2017 — Feb 2018	ENG Engineering	Software Developer @ Andela · LagosOpening balance. Where the books were opened.
Closing balance9 yrs · 10 entries · balanced ✓

Account 02 · Selected work

Transactions worth auditing

Five things I've built. Each one is posted as a debit (what made it hard) and a credit (what shipped).

TXN-001TAX

FIRS e-invoicing platform

Westmetro · Oct 2025 — present

DR: Every ERP has its own dialect, and FIRS accepts exactly one. The invoice must be validated UBL with the right tax identifiers and product codes, or no IRN is issued.
CR: High-throughput Go services on Kubernetes, integrations for six ERP families, and no public ingress to origin. Every integration failure is visible in Grafana.

TXN-002PAY

CentryOS commerce payments

GradientFi · CentryOS · Feb 2026 — Jul 2026

DR: Two commerce platforms with opposite rules about checkout, and a gateway that retries webhooks. Every retry is a chance to pay a merchant twice.
CR: A Shopify offsite payments extension, a BigCommerce middleware with its own Checkout SDK method, and idempotent webhook ingestion checked against production data.

TXN-003ERP

Oyasync hospitality ERP

Oyasync Inc. · May 2022 — Dec 2025

DR: Small fashion and hospitality businesses need proper books, but enterprise ERP is too expensive, too general, and too much.
CR: Three white-labelled products with APIs for mobile and web clients, and a hospitality module now running at 18+ firms.

TXN-004HLTH

FHIR & OpenHIM health interop

Parallelscore · 2020 — 2022 · 2023 — 2025

DR: Open-source health platforms each model patients and encounters their own way, and none of them spoke FHIR out of the box.
CR: Two-way FHIR/HL7 exchange for ERPNext Healthcare, routed through OpenHIM to DHIS2, plus telemedicine built into ERPNext.

TXN-005APP

Storage Sweep

Side project · 2026

DR: Disk-usage tools are either ugly treemaps or "cleaners" you can't trust with your files.
CR: A dependency-free Swift app with a multithreaded fts(3) scanner, a rule-based cleanup advisor, and a fantasy island where your biggest folders are dragons.

Sundry entries

SND-01paginate-info Paginate arrays and work out limit and offset in one call. 300+ weekly downloads.npm package
SND-02EchovonLocal commerce for physical retailers. Made it to the Y Combinator 2020 interview stage.Startup · co-founder
SND-03Email service with RabbitMQ, AWS SES & PM2 Queue-backed transactional email on Node.js.Article
SND-04CI with Node.js, Heroku & GitLab CI/CD A two-part walkthrough of continuous integration from zero.Article · 2 parts
SND-05Sync MongoDB with Kafka & the Kafka connector The on-prem ↔ cloud sync pattern from Echovon, written up.Article

Account 03 · Skills

Chart of accounts

Where the hours have been posted. Payments correctness is the core account; everything else rolls up into it.

1000

Languages

Go · TypeScript · JavaScript · Python · SQL · PHP · Swift

2000

Payments & compliance

Double-entry ledgers · Idempotency & replay protection · Settlement & disputes · Stripe · Shopify & BigCommerce payments · FIRS/NRS e-invoicing (UBL, IRN)

3000

Health interop

FHIR · HL7 · OpenHIM · DHIS2 · EHR integration · ERPNext Healthcare

4000

Backend

Go (Gin, Fiber) · Node.js (NestJS, Express) · Frappe / ERPNext · Flask · REST · GraphQL · OpenAPI · RabbitMQ · Kafka

5000

Frontend

React · Next.js · React Native · Redux · Tailwind · Electron

6000

Data

PostgreSQL · Row-level locking · MongoDB · MySQL / MariaDB · Supabase

7000

Cloud & DevOps

Kubernetes (DOKS) · AWS · Docker multi-arch · GitHub Actions · Nginx · cert-manager · Cloudflare Zero Trust

8000

Observability & testing

Prometheus · Loki · Grafana · Jest · Mocha / Chai

9000

Identity

Multi-tenant SSO · Auth0 · Entra ID · Keycloak · RBAC

Account 04 · The person

Why “Uncle Jabs”?

My middle name is Jabuikem. My little cousins decided that was too much name, so I became Uncle Jabs, and it stuck well enough to end up as this domain.

Mcdavid is the name on the contracts: the engineer who cares whether a webhook retry credits a merchant twice, and who'll reconcile production to prove it didn't. Uncle Jabs is the same person after work: anime on, plantain in the pan.

Anime
Always watching something. Ask me what's on, and expect a long answer.
Plantain
Dodo, boli, chips or porridge, there's no wrong way. Type (or tap) for proof.
Akwete & Nsibidi
The woven bands here borrow from Akwete cloth. The line marks are inspired by Nsibidi. It's Igbo craft on ledger paper.
Lagos, worldwide
Based in Lagos (WAT · UTC+1). I've shipped with teams in New York, Houston and Munich.

Settlement

Let's balance the books.

Hiring a lead? Need a payments, ledger or e-invoicing system built or untangled? I'm open to all three.

DR 01

Full-time

Engineering lead or senior backend roles in payments, fintech or compliance. Remote-friendly, based in Lagos.

DR 02

Contract

Payment-gateway and commerce integrations, ledgers, FIRS/NRS e-invoicing, and ERP integrations (ERPNext, Sage, SAP, QuickBooks).

DR 03

Consulting

Architecture reviews, idempotency and ledger audits, and e-invoicing readiness. I'll find the double-credit before your customers do.

mcdavidemereuwa95@gmail.com