Available to hire
I’m Justine, a Senior Software Engineer based in London with a passion for building scalable, high-performance software and delivering meaningful impact. I design and ship cloud-native solutions across frontend, backend, and data layers, leveraging Python, Rust, Node.js, React/React Native, and containerized infrastructures (Docker, Kubernetes). I thrive on turning complex business needs into robust architectures, leading cross-functional teams, and delivering value in fintech, SaaS, and digital platforms.
Beyond coding, I actively mentor developers, contribute to tech communities, and drive product-led growth through research, GTM planning, and community engagement. I co-founded Faith Fusion Digital Community and have supported tech ecosystems in Tanzania and beyond through open source collaboration, training, and events.
Skills
Experience Level
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Work Experience
Community Lead (Volunteer Part Time) at Ufu m bu zi Labs Academy
January 1, 2025 - November 7, 2025Co-Founder: Ran coding academy for Tanzanian developers, with hands-on mentorship and job preparation.
Software Development & Business Development at Ufumbuzi Labs Limited
September 1, 2024 - September 1, 2024Directed full-cycle software development and business development efforts; designed scalable backend and database solutions; delivered mobile apps and web interfaces; defined system architecture; supported IT operations and onboarding across teams and regions.
Product Development & Quality Assurance at Mixx by Yas (Formerly Tig o Pesa)
September 1, 2024 - November 7, 2025Led end‑to‑end architecture and product development for digital financial products, translating business requirements into PRDs, user journeys, system flowcharts, and architecture diagrams. Implemented robust backend and frontend features, introduced containerized microservices and event‑driven architecture, and addressed scalability. Delivered 5+ enterprise‑grade solutions into production within 6 months, ensuring timely delivery and quality.
Software Development at Ufumbuzi Labs Limited
September 1, 2024 - September 1, 2024Led full-cycle software development across two applications from inception to deployment; designed backend and databases; optimized user flows and delivery; deployed apps on Android and iOS.
Product Development & Quality Assurance at Mixx by Yas (Formerly Tigo Pesa)
September 1, 2024 - November 7, 2025Led end-to-end architecture of digital financial products, translating business requirements into PRDs, user journeys, system flowcharts, and architecture diagrams. Designed robust backend infrastructures with Docker, Kubernetes, and multi-language code (Python and Rust). Shipped 5+ enterprise-grade solutions in 6 months; implemented Last N Transactions to Merchants and introduced containerized microservices and event-driven architecture. Led GTM planning and merchant onboarding initiatives.
Product Development (Remote Work) at Get Paid Africa
August 1, 2024 - August 1, 2024Product research & strategic planning; brand identity & voice; digital marketing leadership; go-to-market execution; customer-centric development with structured feedback loops; sales and community initiatives that improved engagement and onboarding.
Software Development and Business Development at Click Pesa
August 1, 2024 - August 1, 2024Led full-stack software development and business development; designed efficient backend and database systems; improved user flows and onboarding; produced technical documentation; mentored teams and automated workflows using Jira and Bitbucket; contributed to frontend enhancements with React/TypeScript.
Software Developer at Click Pesa
August 1, 2024 - August 1, 2024Led revenue growth through integrated sales and marketing strategies, onboarded 100+ SMEs, built and managed a sales pipeline, and mentored teams on technical product knowledge and consultative selling. Implemented Jira/Bitbucket automation and contributed to frontend improvements using React.
Product Development (Remote Work) at GetPaid Africa
August 1, 2024 - August 1, 2024Conducted product research and strategic planning; defined brand identity and voice; led digital marketing, influencer outreach, and email funnels. Executed go-to-market strategy, focused on customer-centered development, onboarding flows, and UX improvements. Led sales and conversion optimization, community-building, and PR to boost engagement and growth.
Software Development & Business Development at Click Pesa
August 1, 2024 - August 1, 2024Directed revenue growth and GTM efforts; onboarding 100+ SMEs; built and managed a 100+ qualified B2B leads pipeline; delivered product demos, driving client acquisition. Led cross-functional collaboration, introduced Jira/Bitbucket automation, and improved frontend UX with ReactJS. Produced detailed technical documentation and conducted market research.
Community Leader and Mentor at Faith Fusion Digital Community
May 1, 2024 - November 7, 2025Co-founded a community of Young Technologies to empower Africa's youth with digital skills; led teams to build software from ideation to deployment.
Community Lead (Volunteer Part Time) at Atlassian Dar es Salaam
March 1, 2024 - March 1, 2024Led and organized events with 1000+ attendees; mentored 20 developer teams on Atlassian tools; created engaging content increasing participation by 25%.
Frontend Developer at Buni Hub
July 1, 2021 - July 1, 2021Built and deployed responsive web applications; designed RESTful APIs; participated in Agile cycles; collaborated with product and design to enhance UX and cross-device compatibility.
Frontend Developer at The New Boston
March 1, 2021 - March 1, 2021Led frontend UI/UX for Coinratecap, a scalable open-source crypto tracking platform. Built and maintained reusable React.js components with TypeScript. Collaborated with international contributors via GitHub and open-source forums.
Frontend Developer at FST6
January 1, 2021 - January 1, 2021Built a fully functional WordPress-based e-commerce platform; implemented SEO strategies and responsive design; supported SME onboarding with platform demonstrations and user training.
Andela Learning Community Lead at Andela Tanzania
December 1, 2019 - December 1, 2019Organized tech events and coding bootcamps in collaboration with regional partners; curated learning content and hosted mentorship sessions; managed Andela Tanzania’s social presence.
Co-Founder and Team Lead at Kodem Unit
September 1, 2019 - September 1, 2019Co-founded and led a code academy providing software engineering training; designed curriculum, managed delivery of frontend and backend modules; oversaw partnerships, fundraising, and mentorship.
Education
Specialization in Python for Everybody at University of Michigan
November 1, 2016 - November 1, 2020Diploma in Computer Engineering at University of Michigan
November 1, 2016 - November 1, 2020Python for Everybody Specialization at University of Michigan
November 1, 2016 - November 1, 2020Python for Everybody Specialization at University of Michigan
November 1, 2016 - November 1, 2020Startup School at Y Combinator
January 1, 2018 - January 1, 2022Qualifications
Diploma in Computer Engineering
November 1, 2016 - November 1, 2020Responsive Web Design Foundations: Data, Data Everywhere (Google)
February 1, 2019 - June 1, 2021Agile Project Management and Scrum (Open Courses)
March 1, 2023 - November 7, 2025Mentor on Open Courses
March 1, 2023 - November 7, 2025Responsive Web Design Foundations: Data, Data Everywhere (Google)
February 1, 2019 - June 1, 2021Agile Project Management and Scrum (OpenClassrooms)
March 1, 2023 - November 7, 2025Become a Mentor (Open Classrooms)
March 1, 2023 - November 7, 2025Diploma in Computer Engineering
November 1, 2016 - November 1, 2020Responsive Web Design Foundations: Data, Data Everywhere
February 1, 2019 - June 1, 2021Agile Project Management and Scrum
March 1, 2023 - November 7, 2025Mentor on OpenClassrooms
March 1, 2023 - November 7, 2025Industry Experience
Software & Internet, Financial Services, Professional Services
Skills
Experience Level
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
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