Based in Passau, Germany

I build software that stays useful after launch.

Software developer working across Java, Spring Boot, Vaadin, mobile, Docker, and Kubernetes—turning complex product needs into dependable systems.

Let’s work together See selected work

01 / About

Engineering with a product point of view.

I work comfortably from architecture to interface: shaping the backend, integrating data, building the UI, and supporting the path to production.

My experience spans backend services, web applications, mobile products, CI/CD, and cloud-focused deployments. Graduate study complements that hands-on delivery with current technical depth and systems thinking.

  • Java
  • Spring Boot
  • Vaadin
  • JavaScript
  • MySQL
  • Docker
  • Kubernetes
  • Jenkins
  • Flutter
  • REST APIs

02 / Education

Always learning.

2024 — Present

M.Sc. Computer Science

University of Passau

2015 — 2018

B.Sc. Computer Science

Africa Nazarene University

03 / Experience

Building, integrating, and shipping.

—

Full-Stack Developer · Goldvein Solutions Ltd

  • Designed a scalable Java and Spring Boot backend supporting concurrent sales orders from more than 100 retail shops.
  • Containerized a three-service application environment with Docker.
  • Built a Jenkins CI/CD pipeline that reduced deployment time from approximately 10 minutes to 2 minutes.
  • Added JUnit and Mockito tests to detect defects earlier and improve maintainability.

—

Freelance Software Developer

  • Delivered tailored Java, Spring Boot, and Docker applications for three SME clients.
  • Translated business requirements into maintainable technical solutions.
  • Improved operational efficiency by approximately 15% through workflow-focused software.
  • Worked directly with stakeholders from requirements gathering through delivery.
  • Completed AWS re/Start and earned the AWS Certified Cloud Practitioner certification in 2024.

—

Software Developer · eKRAAL Innovation Hub

  • Progressed from Junior Software Developer to Mobile Application Developer and Software Developer.
  • Designed scalable microservice architectures to improve reliability and maintainability.
  • Built cross-platform Flutter applications for Android and iOS.
  • Developed and integrated more than 80 REST APIs across distributed services.
  • Deployed and monitored production environments to improve operational stability.

—

Software Developer Intern · Sematime Ltd

  • Built interactive operational dashboards and a car-hire web application.
  • Created responsive interfaces with Java, Vaadin, and CSS.
  • Contributed to UI/UX design and database integration for reliable application data flows.

—

First-Line Support Developer · Safaricom PLC

  • Supported developers integrating applications with the M-PESA Daraja API.
  • Troubleshot payment integration issues and developed reliable transaction listeners.
  • Published an open-source C# library that simplified M-PESA integration for .NET applications.

04 / Selected work

Systems with real-world jobs to do.

01

IOT · Computer vision · Highway operations

ANPR Highway Dashboard

Built an operational dashboard that validates number plates streamed by AI edge devices against a shared blacklist. Real-time alerts, live tracking, and historical search help enforcement teams identify vehicles of interest sooner.

Impact Turned continuous plate streams into immediate, actionable enforcement information.

  • Java 11
  • Spring Boot
  • Vaadin
  • MySQL
Open ANPR service ↗
02

IoT · Payments · Mobility

Smart Parking Platform

Designed connected APIs for facility onboarding, edge-device deployment, ANPR vehicle entry, time-based fee calculation, and cash or M-PESA settlement.

Impact Automated the journey from vehicle detection to checkout and reduced manual reconciliation.

  • REST APIs
  • ANPR
  • JPA
  • Docker
Open parking service ↗Watch demo ↗
03

Field intelligence · Analytics

Election Intelligence Suite

Created a secure field-reporting workflow and dashboard. Agents capture local issues on Android while decision-makers analyse county, constituency, and ward trends and audit submissions.

Impact Converted distributed observations into structured intelligence for faster campaign planning.

  • Spring Security
  • JWT
  • Android
  • Vaadin
Open dashboard ↗Open API (login required) ↗
04

Civic technology · Geospatial

NTSA Issue Reporting

Developed a mobile-to-dashboard flow that captures precise locations, responsible government bodies, issue categories, and photo evidence, then presents cases as live map markers.

Impact Added geographic and evidential context so teams can route cases and plan informed responses.

  • Maps
  • Mobile
  • Case management
  • Spring Boot
Open NTSA service ↗
05

Traffic analytics · Data visualization

Transtat Admin Dashboard

Administrators can move from a network-wide picture to individual locations, compare changing traffic volumes, and use the connected API documentation to understand the underlying data services.

Impact Replaced fragmented traffic records with one navigable view, making road-use trends easier to monitor, compare, and communicate across locations and time.

  • Vaadin 8
  • Swagger UI
  • Jetty
  • Java
Open Version 2 dashboard ↗API documentation ↗
06

Insurance operations

Insurance Workflow Dashboard

Built a centralized interface for reviewing and managing insurance records through shared services, relational persistence, and a containerized deployment.

Impact Consolidated record handling and enabled consistent deployment with connected ITS services.

  • Java
  • Hibernate
  • MySQL
  • Docker Compose
Open insurance service ↗
07

Open data · Developer tooling

Nairobi Intersection Geocoder

Built a Python utility that matches named road intersections to real shared OpenStreetMap nodes, generates SQL, and flags uncertain results for review.

Impact Replaced error-prone coordinate entry with a repeatable workflow that preserves data quality.

  • Python
  • OpenStreetMap
  • SQL
  • Geospatial data
View on GitHub ↗
08

Fintech · Open source

C# Daraja Libraries

Created reusable .NET libraries that wrap common M-PESA Daraja API workflows in a clearer C# interface. The project gives developers a practical starting point for authentication and payment requests while keeping HTTP communication and request construction out of application-level business logic.

Impact Reduced repetitive integration work, shortened the path to a working C# payment flow, and made M-PESA integrations easier to understand, reuse, and maintain.

  • C#
  • .NET
  • M-PESA
  • REST
View repository ↗
09

Personal finance · Data analytics

Finance Dashboard

Built a Python pipeline that imports bank statements, cleans and classifies transactions with reusable rules, stores them in SQLite, and produces Excel, CSV, monthly cash-flow, and money-leak reports.

Impact Turned raw statements into repeatable spending insights, with a Streamlit review workflow that improves future classifications.

  • Import and clean raw bank transactions automatically.
  • Review classifications and reuse corrections as future rules.
  • Generate cash-flow, spending, and money-leak reports.
  • Python
  • SQLite
  • Streamlit
  • Excel
View on GitHub ↗
10

Field sales · Offline-first mobile

GVS Sales App

Built a multi-tenant field-sales platform that guides representatives from outlet discovery and NFC, QR, or location-based visit confirmation through product selection, order review, and submission. Downloaded business data and a retry queue keep the core pre-sales workflow available when connectivity drops.

Impact Brought visit verification, pack-and-piece order capture, pricing, and daily sales visibility into one dependable field workflow.

  • Android
  • Offline sync
  • Multi-tenant
  • NFC & QR

A hosted demonstration is available by request. Contact me for demo access and sign-in details.

Open demo server ↗Request a demo ↗

05 / Contact

Have an interesting problem?
Let’s talk.

Passau, Germany