Currently shipping regulated payroll infrastructure at APS Payroll

Architecting resilient systems & engineering culture.

Emmanuel IdowuSenior Software Engineer · Full-Stack, Integrations & AI

Senior software engineer with 10+ years building distributed, integration-heavy backends, most recently in a regulated payroll/HR system of record, where I designed a partner webhook platform, modernized accounting integrations (Sage Intacct, QuickBooks, NetSuite, Restaurant365), and shipped secure, compliant services handling employee PII and money movement. Polyglot across C#/.NET, PHP/Symfony, TypeScript/React, Java/Spring Boot, and Scala, with depth in CQRS, event-driven design, OAuth 2.0/OIDC, and cloud (AWS, GCP, Docker, Kubernetes). A daily AI-augmented developer (Claude Code, Gemini and Codex) building toward production LLM, RAG, and agent systems.

10+
Years of Experience
120+
Tickets Shipped to Production
90%
Reduction in Location-Spoofing Incidents
5+
Languages in Daily Use

System Architecture & Technical Deep Dives

A few of the harder architectural trade-offs behind recent work.

Partner Webhook Platform

APS Payroll · Nov 2024 – Present

A generalized webhook platform spanning .NET microservices and SQL Server: per-partner/per-event subscriptions, a transactional outbox, an event-coalescing service, and signed delivery with exponential backoff, jitter, dead-lettering, and at-least-once semantics.

$ tradeoff --explain
Rolled out with zero impact to the existing partner flow — the outbox and coalescing service had to sit alongside live traffic without a cutover window.

Zero-impact rollout alongside a live partner integration

.NETSQL ServerHMAC-SHA256Transactional Outbox

Sage Intacct Integration Modernization

APS Payroll · Nov 2024 – Present

Ran REST-vs-XML and OAuth 2.0 research spikes, authored the architecture decision for a hybrid XML/REST client abstraction, and drove the build.

$ tradeoff --explain
Sage Intacct's REST coverage is incomplete, so the abstraction had to bridge legacy XML endpoints and modern REST behind one client interface rather than picking one.

One client abstraction, two API generations

OAuth 2.0/OIDCRESTXMLSage Intacct

Company-wide Notification Center & Task Widget

APS Payroll · Nov 2024 – Present

A multi-channel (in-app, email, SMS) notification platform with per-module types, ESS/admin permission models, SMS opt-out, and templating across PHP and Scala services — the largest single program of work on the team.

$ tradeoff --explain
Had to unify notification semantics across two service languages (PHP and Scala) and every existing product module without breaking module-specific permission models.

Largest single program of work shipped at APS

PHP/SymfonyScalaMulti-channel delivery

AI Governance Platform

Algoralign · 2023

Architected an 18-module AI governance platform with production multi-model LLM integrations (Gemini, OpenAI, Claude, DeepSeek), delivered on Express.js, WhatsApp Cloud API, React, and Redis.

$ tradeoff --explain
Governance logic had to stay provider-agnostic across four LLM vendors with different tool-calling and safety-filter behavior.

18 modules, 4 production LLM providers

Express.jsWhatsApp Cloud APIReactRedis

Engineering Essays & Thought Leadership

Prompt engineering can address local challenges in Nigeria

Published Article·2024#PromptEngineering#AI

React Native UI Components

Technical Guide·2024#ReactNative#UI