Samuel Okello

Mobile engineer with production experience in Kotlin, Jetpack Compose, and Kotlin Multiplatform, currently building payments and real-time features for a KMM marketplace app. Built a full on-device computer-vision pipeline (CameraX, OpenCV, Google ML Kit) for ID-document scanning, plus NFC passport reading across Android and iOS. Solo-designed and shipped a crowdsourced transport app to the Google Play Store.

Comfortable across MVVM/MVI and clean architecture, RESTful API integration, offline-first data persistence, and cross-functional product delivery.

Mobile Engineer (Android | Ios) at Mouv Africa (2026-01 – Present)

• Ship features on a Kotlin Multiplatform (KMM) real estate and multi-service marketplace app, sharing business logic across Android and iOS via Compose Multiplatform.
• Built the payment strategy/factory system supporting M-Pesa STK push and PayPal, with socket-based confirmation as the sole automatic payment channel.
• Designed a WebSocket-based real-time event bus using Kotlin SharedFlow for payment-scoped, fan-out delivery.
• Implemented cross-platform location services with an expect/actual pattern FusedLocationProviderClient on Android, CLLocationManager on iOS, powering nearby/recommended listings via Haversine-based distance calculations.
• Diagnosed and fixed production issues including a null Firebase ID token mid-session, concurrent token-refresh races, and navigation route serialization defects.
• Work within a multi-module codebase, participating in PR review and release processes alongside senior engineers.

Android Developer Intern at Mentorlst (2023-10 – 2024-04)

• Designed and implemented application features using Jetpack Compose, translating Figma design specifications into pixel-perfect, responsive UI components aligned with brand guidelines.
• Developed end-to-end search functionality combining real-time API queries via Ktor Client with Room-backed local persistence, enabling offline access to previously fetched results and improving perceived performance on intermittent connections.
• Implemented secure GitHub OAuth2 authentication, broadening user sign-in options and reducing friction during onboarding while maintaining secure token handling on device.
• Collaborated with cross-functional teams including UI/UX designers and backend engineers, participating in stand-ups and sprint planning to ensure smooth API contract alignment and timely feature delivery.
• Wrote unit tests and participated in code reviews, focusing on edge case handling, error states, and overall application reliability across supported Android versions.

Bachelor of Science in Computer Science – Kibabii University