Available to hire
Hi, I’m Joseph Musyoka Muasya, a passionate Senior Software Engineer with extensive experience in mobile and backend development. I’ve worked on a variety of projects, from building Mixed Martial Arts training apps to leading integrations for Mastercard’s Community Pass solutions. I enjoy collaborating with cross-functional teams to create high-quality, scalable, and user-friendly applications.
With a background in Android development and strong expertise in Kotlin, Spring Boot, and Flutter, I strive to deliver exceptional solutions that meet both technical and business needs. I love solving complex problems and continuously learning new technologies to stay ahead in the fast-evolving tech industry.
Experience Level
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Language
English
Fluent
Work Experience
Senior Software Engineer, Purchase at Mastercard Inc
July 31, 2025 - July 25, 2025As a Solution Sales Engineer, I worked alongside the Customer Success Manager co-owning pre-sales and post-sales integration processes. I collaborated with markets to sell solutions by enhancing sales communication, and partnered with customer technical teams as tech lead to implement integrations. I led 4 successful integrations in Uganda and India, authored solution design and integration documentation, and led internal testing to identify and resolve API issues, improving product quality and avoiding potential billing issues.
Founding Android Engineer at Kayyo
June 1, 2024 - PresentCollaborated in a small cross-functional team to develop a Mixed Martial Arts training app from post-release to feature-rich Version 3. Enhanced app stability achieving over 98% crash-free sessions and a 4.6+ star rating. Drove revenue growth from zero to revenue-positive, scaling user base from under 60,000 to over 300,000 in six months with 30,000+ monthly active users.
Senior Software Engineer at Ewave
December 31, 2024 - July 25, 2025Led a cross-functional team in design, architecture, development, and iteration of an event management app. Accelerated development by 60% by designing clear app architecture and fostering team collaboration. Improved microservice communication speed by 3x using gRPC over RESTful protocol. Achieved 78% test coverage for backend and android app, leading to 98% crash-free app performance.
Android Engineer at Climax Publishers
April 30, 2024 - July 25, 2025One of two android engineers who implemented the Soma Sasa App from concept to production.
Senior Android Engineer at Doctors Live Inc.
June 30, 2023 - July 25, 2025Collaborated with cross-functional team to improve performance of mental health telemedicine app. Reduced app vulnerabilities below 10% through memory management and certificate pinning. Improved network efficiency by 27% via asynchronous network monitoring and efficient data caching.
Mobile Engineer at Dukatech Solutions Ltd
June 30, 2022 - July 25, 2025Worked with startup team to launch ShopOkoa app connecting Buy-Now-Pay-Later merchants to customers. Implemented payment SDK integrations increasing merchant adoption by 129%. Collaborated with marketing team to incorporate customer feedback in apps improving user experience. Developed backend and android app for Sokobeauty end-to-end.
Android and Java Developer at Immicart Shopping
July 31, 2020 - July 25, 2025Developed last mile delivery apps Immicart and Immicart furniture. Worked with startup team to launch furniture app aiding employees working from home. Translated UI designs into adaptive user interfaces.
Android Engineer at Shopleo
September 30, 2019 - July 25, 2025Developed first self-checkout system for supermarkets and translated UI designs into adaptive user interfaces.
Senior Software Engineer, Purchase at Mastercard Inc
July 31, 2025 - July 25, 2025Worked alongside the Customer Success Manager, co-owning technical pre-sales and post-sales integration processes. Collaborated with markets to sell solutions enhancing sales communication with technical details of Mastercard Community Pass. Led 4 successful integrations in Uganda and India, supporting pre-sales and post-sales phases. Updated documentation for clarity and compliance with standards, authored solution design and integration documents for technical and non-technical audiences. Led internal testing (dogfooding) of solutions and APIs, identifying integration issues early and serving as a bridge between engineering, product, and marketing teams. Identified major API implementation error preventing potential billing issues.
Founding Android Engineer at Kayyo
June 1, 2024 - PresentCollaborated in a small cross-functional team to develop a Mixed Martial Arts training app from post-release to feature-rich Version 3. Enhanced app stability achieving over 98% crash-free sessions and a 4.6+ star rating on Google Play Store. Scaled user base from under 60,000 to over 300,000 in six months with 30,000+ monthly active users, driving revenue growth from zero to revenue-positive.
Senior Software Engineer at Ewave
December 31, 2024 - July 25, 2025Led a cross-functional team in design, architecture, development and continuous iteration on Ewave event management application. Accelerated development by 60% by designing clear app architecture using MVI pattern and fostering team collaboration. Achieved 3x speed on microservice communication by using gRPC protocol over RESTful. Maintained 78% test coverage improving error identification and troubleshooting, leading to 98% crash free app.
Android Engineer at Climax Publishers
April 30, 2024 - July 25, 2025One of two Android engineers who implemented Soma Sasa App from concept to production.
Senior Android Engineer at Doctors Live Inc.
June 30, 2023 - July 25, 2025Collaborated with cross-functional team to improve performance of mental health telemedicine app. Reduced app vulnerabilities to below 10% through efficient memory management and certificate pinning. Improved network efficiency by 27% by implementing asynchronous network monitoring and efficient data caching.
Mobile Engineer at Dukatech Solutions Ltd
June 30, 2022 - July 25, 2025Worked with startup team to successfully launch ShopOkoa app connecting Buy-Now-Pay-Later merchants to customers. Implemented payment SDK integrating Flutterwave and Mpesa SDKs, increasing adoption by 129%. Collaborated with marketing team to incorporate customer feedback improving user experience on ShopOkoa and Bosslady apps. Developed Sokobeauty backend and Android app end to end.
Android and Java Developer at Immicart Shopping
July 31, 2020 - July 25, 2025Developed last mile delivery apps: Immicart and Immicart furniture. Collaborated with startup team to launch Immicart furniture aiding remote workers. Translated UI designs into adaptive interfaces.
Android Engineer at Shopleo
September 30, 2019 - July 25, 2025Developed first self-checkout system for supermarkets. Translated UI designs into adaptive interfaces.
Education
Bsc. Mechanical Engineering at Jomo Kenyatta University of Agriculture and Technology Juja, Kenya
January 1, 2021 - December 31, 2021Bsc. Mechanical Engineering at Jomo Kenyatta University of Agriculture and Technology Juja, Kenya
January 1, 2018 - December 31, 2021Qualifications
Financial Analyst and Valuation Analyst (FMVA) and Business Intelligence and Data Analysts (BIDA)
January 1, 2022 - December 31, 2022Google Project Management: Professional Certification
January 1, 2022 - December 31, 2022Android Developer Certification
January 1, 2018 - December 31, 2018Financial Analyst and Valuation Analyst (FMVA) and Business Intelligence and Data Analysts (BIDA)
January 1, 2022 - December 31, 2022Google Project Management: Professional Certification
January 1, 2022 - December 31, 2022Google Africa Developer Scholarship — Android Developer Certification
January 1, 2018 - December 31, 2018Industry Experience
Software & Internet, Financial Services, Healthcare, Retail, Professional Services
Experience Level
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
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