Stephen Maina
Wainaina

Backend Software Developer · Java Spring Boot · Laravel · System Integration

I build scalable enterprise applications, backend systems, REST APIs, payment integrations, and business automation solutions that solve real-world business challenges.

View My Work → ⬇ Download Résumé

01. About

Engineering reliable systems

I am a Software Developer specializing in backend engineering and enterprise software development with over five years of experience building scalable business applications.

My expertise spans Java Spring Boot, Laravel, REST API development, payment gateway integrations, cloud deployments, database optimization, and enterprise system integrations. I have led architectural migrations from monoliths to decoupled systems.

Throughout my career I have designed and developed systems used in finance, retail, security, CRM, logistics, taxation, visitor management, and SaaS platforms. I enjoy solving complex business problems through clean architecture, scalable design, and automation.

Quick facts

LocationNairobi, Kenya
FocusBackend / DevOps
EducationBSc Applied Comp. Science
LanguagesEnglish, Kiswahili
Open toContract & Full-time

02. Skills

Tech stack & toolbox

The technologies I reach for when designing, building, and shipping production systems.

Backend

Java 21Spring BootSpring Security Spring Data JPAPlay FrameworkLaravel PHPCodeIgniter

Frontend

React.jsVue.jsThymeleaf JavaScriptHTML5CSS3TailwindLivewire

Databases

MySQLPostgreSQLSQLite SupabaseH2

Cloud & DevOps

DockerGitGitHub Oracle CloudAWS

Integrations

REST APIsM-PesaDPO JambopayKRA eTIMSSMS APIsEmail APIs

Testing & Tools

JUnit5MockitoPHPUnit PostmanIntelliJ IDEADBeaver

03. Experience

Where I've worked

Backend Developer (Contract)
SGA Holdings Limited
March 2025 – Present
  • Architect and develop microservices-based systems using Java 21, Spring Boot, and MySQL.
  • Built the eTIMS Middleware bridging OMNI ERP finance with KRA eTIMS (VSCU) for automated invoice signing and submission.
  • Implemented M-Pesa & DPO payment integrations and OMNI ERP ↔ KRA finance integration via Total Solution APIs.
  • Improved system performance by 40% and integrated government/financial APIs with 99.9% uptime.
Full Stack Software Developer (Contract)
Uzapoint Limited
August 2024 – February 2025
  • Led architectural transformation from monolith to decoupled Vue.js + Laravel microservices.
  • Optimized a multi-tenant SaaS POS platform with CRM, HRM, and Payroll modules.
  • Reduced system resource usage by 35% and managed a team of 4 developers through the migration.
Software Developer
Deveint Limited
January 2023 – August 2024
  • Developed backend services with PHP (Laravel, CodeIgniter) and designed RESTful APIs for system integration.
  • Delivered FedhaTrac, SokoFlow, MojaPass, Real Sources Africa, and Agnet platforms as technical lead.
  • Led 5+ major projects with 100% on-time delivery and mentored 3 junior developers.
Junior Software Engineer (Management Trainee)
Velocis Technologies Kenya
January 2022 – June 2022
  • Built Java / Spring Boot backend systems and deployed on Oracle Cloud with 99.5% uptime.
  • Developed an online file-scanning app using Spring Boot and ClamAV APIs for malware detection.
  • Earned Oracle OCI Foundations and AWS Cloud Foundations certifications.

04. Projects

Featured work

A selection of production systems I've designed, built, and shipped for real businesses.

📁
Live ↗

eTIMS Middleware

A bridge between OMNI ERP and KRA eTIMS (VSCU) that automates invoice generation, signing, and submission, with validation alerts and reporting for the finance team.

Java 21· Spring Boot· JUnit5· MySQL
📁
Live ↗

Enterprise Monoliths Platform

In-house suite: a CRM microservice, a React self-service customer portal, a Thymeleaf admin portal, M-Pesa C2B payments, and a KRA eTIMS tax-compliance module.

Spring Boot· React· Thymeleaf· Docker
📁
Live ↗

Uzapoint POS Suite

Multi-tenant SaaS point-of-sale platform with CRM, HRM, and Payroll modules, migrated from a monolith to a decoupled Vue.js + Laravel architecture.

Laravel· Vue.js· MySQL
📁
Live ↗

FedhaTrac

Personal finance management platform with budget tracking, investment modules, custom loan-management APIs, SMS/Email OTP, and M-Pesa / Jambopay payments.

Laravel· Livewire· MySQL
📁
Live ↗

SokoFlow SaaS

Commodity-trading automation platform serving multiple B2B clients (Sidai, Kenmeat, Hallmark) with order management, sales tracking, and reporting.

Laravel· Livewire· MySQL
📁
Live ↗

MojaPass VMS

Digital visitor and resident management platform with real-time data capture, registration, verification, and security-focused identity tools with fraud prevention.

Laravel· Livewire· Tailwind
📁
Live ↗

Event Ticketing System

Ticketing and event management platform handling event listings, ticket sales, and payment processing for organizers and attendees.

Laravel· REST API· MySQL
📁
Live ↗

More Platforms

Additional shipped products: BuyaLot (e-commerce), Kiyovu Sports Club, Bianlina, and the Agnet marketing platform for Tanzania Commercial Bank.

Laravel· Vue.js· PHP

05. Credentials

Certifications & links

🏅 Certifications

  • Oracle OCI Foundations Certified
  • Oracle Developer Certificate
  • AWS Cloud Foundations
  • CISCO — Introduction to Cybersecurity

🔗 Live deployments

buyalot.africa↗ kiyovusports.rw↗ bianlina.com↗ ticketspride.com↗

06. Contact

Let's build something

I'm open to backend and full-stack opportunities, contract work, and interesting technical challenges. The fastest way to reach me is by email.

✉ stevenmaina17@gmail.com 📞 +254 710 767 015