terminal BS.

Senior Full Stack Engineer

Brian Mahindu Sanzio

Modernization and high-throughput systems specialist across PHP, Node.js, Vue, and NestJS ecosystems. Building resilient cloud-native platforms where uptime, throughput, and developer velocity matter.

Nairobi, Kenya (UTC+3) Remote Expert

Professional Profile

What I Build

Pragmatic and performance-driven engineer with 4+ years of experience architecting and modernizing high-throughput digital platforms. Strong in Symfony/Laravel ecosystems, Doctrine ORM, and AWS cloud-native architecture. Proven in transitioning legacy monoliths into modular services while sustaining 99.9% uptime for systems serving 30,000+ users. Deep hands-on work in SQL optimization, Redis caching for high-frequency workloads, observability with DataDog/CloudWatch, and AI-assisted development to accelerate delivery.

Core Technical Skills

Stack and Specialization

Backend Mastery

  • PHP 7.2 - 8.3 (Expert)
  • Symfony 5.x/6.x, Laravel
  • Doctrine ORM
  • Node.js, TypeScript, NestJS
  • Vue.js

Architecture

  • Monolith to microservices modernization
  • Domain-Driven Design (DDD)
  • API-first design
  • Event dispatchers, dependency injection

Data and Performance

  • MySQL indexing and optimization
  • Redis, PostgreSQL, Memcached
  • High-throughput API performance tuning

Cloud and Infra

  • AWS ECS, Lambda, S3, API Gateway
  • Docker, Linux/Ubuntu SysAdmin
  • Terraform, GitHub Actions CI/CD

Observability and QA

  • DataDog and CloudWatch
  • PHPUnit, TDD, Mockery
  • Swagger / OpenAPI

Frontend and Tooling

  • jQuery, SASS, responsive UI/UX
  • Git, Copilot, Cursor
  • AI-assisted SDLC acceleration

Professional Experience

Impact Across Roles

Software Engineer II - Full Stack Engineer | Daktari Online

Jan 2025 - Present
  • Leading monolith decoupling into microservice-oriented architecture with domain isolation and scalable API integrations.
  • Managing ERP and LLM-integrated platform serving 30,000+ users across Africa with high availability.
  • Optimized Doctrine/MySQL queries and indexing, reducing report latency by 35% and improving request throughput.
  • Architected AWS Lambda, ECS, and API Gateway services with 99.9% reliability for healthcare workflows.
  • Built payment flow handling micro-transactions as low as $0.50 and generating $12,000 in first quarter.
  • Improved observability with DataDog and custom alerts, reducing incident resolution time by 30%.

Full Stack and DevOps Engineer | Cleanconex

Mar 2024 - Dec 2025
  • Scaled marketplace launch across Australia, UK, and Philippines supporting 5,000+ daily transactions.
  • Designed idempotent REST APIs and secure payment integrations (Stripe, PayPal, GoCardless).
  • Owned Dockerized deployments and GitHub Actions CI/CD for fast and reliable release cycles.
  • Hosted and tuned high-concurrency billing engines on AWS with observability and cost-aware scaling.

Technical Lead | Big Brainz Solutions

Jan 2023 - Dec 2025
  • Developed insurance claim system transacting $100,000+ with reconciliation and robust failure handling.
  • Refactored legacy procedural systems into modern, testable Symfony patterns.
  • Built internal automation and AI-assisted refactoring spikes, saving 15+ engineering hours weekly.
  • Mentored junior developers and enforced code quality via PHPUnit/Mockery and peer reviews.
  • Engineered KRA eTIMS integration for 50+ schools with compliance and performance requirements.

Junior Software Engineer | Afrisyntech

Jan 2022 - Dec 2022
  • Built PHP 7.2, jQuery, and SASS modules in MVC architecture while following team standards.
  • Participated in Scrum ceremonies, estimations, and task refinement.

Key Contributions

Beyond Day-to-Day Delivery

AI-Enhanced SDLC

Adopted AI for unit test generation, legacy code documentation, and faster technical spikes.

Payment Engine

Designed high-volume billing engine using Redis rate limiting and asynchronous queue processing.

Symfony Bundles

Created reusable bundles for standardized API responses and error handling across services.

Projects

Live Products

Daktari Online Platform

Health-tech LMS for healthcare professionals.

Daktari Webinars

Live and recorded medical training platform.

Metropoly ERP System

Enterprise operations and workflow ERP platform.

CleanConnex

Cleaner-customer marketplace for UK and Philippines.

Delight Funerals System

Insurance claims and policy administration platform.

Cash-Flow App

Expense and cash-flow management platform.

iReceipts

KRA eTIMS tax compliance and e-receipt system.

Digiskool Academy

Children and teen focused digital skills academy.

Wordeos

Word guessing game with streak and hint mechanics.

Education

BSc in Software Development

KCA University, Nairobi

References

Available Upon Request

Professional references can be shared during interview process.

Contact

Let's Build Something Serious

Open to remote and hybrid full stack opportunities focused on scale, modernization, and reliability.

Portfolio GitHub