Discipline Full stack
Domain Fintech · Insurance
Base Manila, PH
In practice 9 yrs · since 2017

Open to new roles Senior Full Stack Developer

Karekezi Caleb
Buhungiro

I build the systems that carry regulated money.

Nine years designing, building and shipping production software across fintech, insurance, hospitality and enterprise platforms — Java and Spring Boot microservices running on Kubernetes, and the React and Flutter interfaces people actually use. A product I helped architect is in production today, serving thousands of users.

Download resume karekkhaleb@gmail.com
Portrait of Karekezi Caleb Buhungiro
Manila, Philippines
  • 01

    End to end ownership

    Architect through production and into operations — decided platform architecture, ran Kubernetes and GitOps delivery, and shipped a consumer food delivery app solo from first commit to production.

  • 02

    Polyglot stack

    Java and Spring Boot microservices, Ruby on Rails, Python and Django, Node, PHP and Laravel, Flutter, and C++ with Unreal Engine — chosen to fit the problem rather than collected.

  • 03

    Regulated fintech

    Loans, credit cards and insurance compared across Malaysia, on a production platform serving thousands of users — running on Consul, Redis, Keycloak, Kubernetes and AWS.

Selected work

Things I have built

Three products I have shipped or worked on — a food delivery platform I built end to end, and the fintech and hospitality platforms behind two larger teams.

HatodNow, a food delivery platform: its landing page with the Android download call to action
01 hatodnow.net ↗

HatodNow

A food delivery platform for my hometown in Negros Occidental — designed, built, deployed and running in production, with live rider tracking and a separate driver app.

  • Built the whole product solo — Laravel API and admin panel, plus two Flutter apps for customer and rider.
  • Built live order tracking that moves the rider on the map from kitchen to doorstep, with status updates at each step.
  • Shipped Google sign-in with SMS verification, saved addresses, and cash-on-delivery checkout with fees shown before payment.
Flutter Dart Laravel PHP REST APIs
LoanStreet, a Malaysian financial comparison platform: its product grid of personal loans, home loans, car loans, credit cards and insurance
02 loanstreet.com.my ↗

LoanStreet

A Malaysian financial comparison platform for loans, credit cards and insurance, built as a polyglot system — a React front end, a Ruby on Rails core, and a set of Java Spring Boot microservices.

  • Worked on the Java Spring Boot microservices that sit between the Rails core and the React front end.
  • Services used Consul for service discovery and configuration, with Redis and Keycloak behind the API gateway.
  • Deployed on Kubernetes and AWS behind CI pipelines with SonarQube quality gates on every build.
Java Spring Boot Microservices React Ruby on Rails Redis Keycloak Kubernetes
GroupSync, a group hotel booking marketplace: its landing page headline and property search form
03 groups360.com ↗

GroupSync

A B2B marketplace where meeting planners, sports teams and weddings book group rates across more than 200,000 properties — React front end, Django back end.

  • Built and maintained Python services behind property listings, room availability and booking workflows for a multi-region user base.
  • Developed reusable React components so listing and booking screens stayed consistent across the platform's markets.
  • Helped move the platform from a monolithic application to microservices, giving each domain independent deployment.
Python Django React REST APIs Microservices

Experience

Where I have worked

  1. 2017 → 2026 · 9 yrs 2 mos
  2. Mar 2023 – Present 3 yrs 6 mos

    Senior Software Developer

    Finology Sdn Bhd · Malaysia

    • Lead a team of 5 engineers — 2 frontend, 3 backend — setting code standards and code review practices across the group.
    • Decided the architecture of a fintech product in production today, serving thousands of users across health and automotive insurance.
    • Provision and operate Kubernetes workloads on Azure Kubernetes Service, covering deployment, scaling and ingress configuration.
    • Run services on AWS EC2 and Lightsail, sizing each environment against cost and performance.
    • Set up GitOps continuous delivery with ArgoCD, making every deployment automated, auditable and reversible.
    • Build CI/CD pipelines across Azure and AWS that automate build, test and release.
    • Introduced monitoring and alerting for production workloads, improving deployment reliability and reducing downtime.
    • Build a cross-platform Flutter app for Android and iOS from a single codebase, integrated with existing backend APIs to give mobile users full feature parity with web.
    Java Spring Boot Kubernetes ArgoCD AWS Azure React Flutter
  3. Apr 2022 – Mar 2023 11 mos

    Full Stack Developer

    Luxoft · Malaysia

    • Contributed to a global hospitality and real estate booking platform for a US-headquartered client operating across multiple international markets.
    • Built and maintained Python backend services powering property listings, room availability and booking workflows for a multi-region user base.
    • Developed reusable React components for the listing and booking interfaces, keeping UX consistent across the platform's markets.
    • Helped migrate a monolithic application to a microservice architecture, improving scalability and deployment independence.
    Python React Microservices REST APIs
  4. Mar 2019 – Apr 2022 3 yrs 1 mo

    Full Stack Developer

    Finology Sdn Bhd · Malaysia

    • Developed purchase and management dashboards for an insurance platform bridging banks and insurance providers.
    • Built Java / Spring Boot microservices carrying core business logic, and handled deployments for AWS-hosted applications.
    • Developed React and TypeScript interfaces, and managed the Linux servers and automation scripts behind them.
    • Ensured application security and integration across multiple APIs and databases.
    • Partnered with PMs, developers and QA on problem-solving, testing and best practices.
    Java Spring Boot React TypeScript AWS Linux
  5. Jul 2017 – Mar 2019 1 yr 8 mos

    Full Stack Developer, Freelance

    Self-employed · Rwanda

    • Delivered projects for clients including Never Again Rwanda (NAR) and the Peacebuilding Institute (PBI).
    • Worked extensively with Laravel, Drupal and WordPress.
    • Built front-end and back-end features with Bootstrap, Material CSS, Express and Node.js.
    • Implemented unit and integration tests with Jest, Mocha and Jasmine.
    Laravel Drupal WordPress Node.js Express

Capabilities

What I work with

Most of my depth is in Java and Spring Boot on the back end and React on the front. The mobile and game work is less common, and it means I can carry an idea all the way from a service to a client app without a handover.

Frontend

  • React
  • TypeScript
  • Vue
  • JavaScript
  • HTML5
  • CSS3
  • Tailwind
  • Bootstrap

Backend

  • Java
  • Spring Boot
  • Node.js
  • Python
  • Django
  • PHP
  • Laravel
  • Bash

Cloud & DevOps

  • Azure
  • AWS EC2
  • Lightsail
  • Docker
  • Kubernetes
  • AKS
  • ArgoCD
  • GitOps
  • CI/CD
  • Linux

Mobile

  • Flutter
  • iOS & Android
  • Dart
  • REST integration

Databases

  • PostgreSQL
  • MySQL
  • MongoDB
  • API integration

Architecture & practice

  • Microservices
  • System design
  • Tech leadership
  • Code review
  • Jest
  • Mocha
  • JUnit
  • Cypress

Also C++, Unreal Engine, Travis CI, CircleCI, Windows, macOS

Education

Background

2013 – 2017

Bachelor of Science

University of Rwanda

2009 – 2012

MPC

Lycée de Kigali · Mathematics, Physics and Computer Science