Hey I'm Osborn
Mobile engineer
Mobile Engineer specializing in native development with clean architecture (MVVM/MVI), writing scalable, test-driven code that delivers premium user experiences.
Experience
Mobile Application Engineer
Roamtech Solution
Mar 2025 – Present
Nairobi (Hybrid)
- Architected and rewrote the flagship international money transfer (IMT) mobile app (Afrisend) from native Kotlin/Java to Flutter, scaling the application to process over 2,000+ monthly global remittance transactions across 100+ active downloads.
- Integrated secure backend REST APIs supporting multi-channel payouts—including M-Pesa and international bank transfers—enabling instant cross-border payments for African diaspora users.
- Engineered the UK-focused Tumatuma remittance app using Flutter and feature-based modular architecture, utilizing bloc_concurrency to ensure reliable event handling during high-volume multi-step payout flows.
Projects
Tumatuma App
Overview
Engineered the mobile banking and remittance platform enabling diaspora users in the UK to complete cross-border money transfers. Features a modular architecture using BLoC concurrency, Veriff identity verification (KYC), and real-time WebSockets.
Tech stack
Resources
Nafusite Mobile App
Overview
A native Android mobile application built to demonstrate clean architecture, robust state management, and modern Kotlin development principles.
Tech stack
Resources
PixStream
Overview
Addresses disrupted user experiences during network drops, where refreshing forces loss of progress. Resolves this by using real-time connection monitoring and local state preservation to seamlessly resume media fetching from the exact point of interruption without loading unintended new content.
Tech stack
Resources
Case Studies
Offline-First Data Synchronization
The Challenge
Application failure and data loss when users attempted critical cross-border transactions or viewed account details in low-connectivity environments.
How I Solved It
Architected an offline-first data layer that persists user state locally, allowing seamless app operation offline and queuing background sync tasks until network connectivity is restored.
Platform & Tech
High-Performance HTTP Caching Strategy
The Challenge
Slow initial screen loads and excessive API usage caused by fetching fresh remote data on every screen navigation.
How I Solved It
Implemented robust HTTP caching protocols using conditional headers (ETags / Cache-Control) and local cache fallbacks, drastically speeding up data load times and minimizing redundant network payloads.
Platform & Tech
CDN Media & Network Resource Optimization
The Challenge
High latency and increased bandwidth costs caused by delivering unoptimized static assets and heavy media files directly from origin servers.
How I Solved It
Configured a global Content Delivery Network (CDN) edge-caching layer with automated dynamic image compression and asset minification, significantly accelerating global delivery times and reducing origin server load.