React Native mobile engineering
React Native, Expo and TypeScript for Android and iOS software; architecture, authentication, APIs, device features, testing and app release.
Related company serviceMeet the founder
Joel Mbaka
Founder of Joeltech Geek Systems · Senior Full-Stack Software Engineer · React Native Specialist
I founded Joeltech Geek Systems to build useful software for businesses and develop commercial products of our own. I lead the architecture and hands-on engineering behind mobile apps, web dashboards, backend systems, payment integrations and product releases.
Based in Nairobi, Kenya, I work with remote clients and engineering teams internationally. I am open to relevant senior React Native, full-stack product engineering and technical-lead roles, as well as scoped software projects through Joeltech Geek Systems.
Engineering leadership and specialization
My core focus is production mobile and full-stack product engineering, not listing every technology as a separate service. React Native is our primary mobile framework—not Flutter or standalone native Swift/Kotlin development.
Next.js and full-stack web engineering
React/Next.js applications, responsive dashboards, operational workspaces and business workflows.
Related company servicePython backend architecture
FastAPI, PostgreSQL, SQLAlchemy, Alembic, permission boundaries and transactional API design.
Related company servicePayments, AI integration and delivery
M-Pesa reconciliation, validated callbacks, applied AI APIs, test automation and production release workflows.
Related company serviceProducts and client systems I've helped build
Technical evidence matters more than a job title. These case studies distinguish products developed within our business from commissioned client work and show the platforms actually built.
Company-developed product
RentPayor
iOS · Android · Web dashboard
Rent collection and reconciliation software for landlords and property managers. RentPayor connects iOS and Android apps with a web management dashboard for landlords and property managers. It handles properties, leases, rent invoicing, M-Pesa collections, partial payments, automatic reconciliation, receipts, credits and reporting.
View engineering case studyCompany-developed product
JournPad: Voice Journal
iOS · Android
Voice-first journaling app that preserves the original recording, transcribes spoken entries, and uses AI to generate useful titles, summaries, and categories. Entries can be searched and revisited by date, linked to goals, supported by reminders and prompts, and protected with account, deletion, and optional biometric controls.
View engineering case studyCompany-developed product
SchoolPey
Android · Web dashboard
School-fee billing and collection software with an Android parent experience and web administration dashboards for schools. Manages students, guardians, term invoicing, M-Pesa payments, receipts, balances and reconciliation.
View engineering case studyCompany-developed product
CliviQue HMIS
Web platform · Backend
Hospital management information system connecting patient registration, OPD, emergency, inpatient care, orders, referrals, theatre, billing, ambulance, mortuary, duty coverage, patient movement, documents, and facility operations. It includes facility-bound Tuma M-Pesa patient billing and reconciliation, alongside SaaS subscription billing infrastructure.
View engineering case studyClient project
Macsim Cargo
Android · Web administration
Cargo and logistics operations platform spanning mobile field workflows and back-office administration. Macsim handles loads, reservations, driver assignments, trip tracking, documents, notifications, fleet operations and finance, with a guarded M-Pesa/Daraja flow for funding a collection-account ledger and paying drivers in full or partial load installments.
View engineering case studyClient project
Milliol Construction Manager
Android
Android construction-operations application for project progress, work items, procurement, inventory and stock, financial tracking and operational reporting.
View engineering case studyFounder, engineer and mentor
I hold a BSc in Information Technology from JKUAT and support emerging developers through practical learning and feedback. My company also welcomes enquiries about engineering collaboration, remote roles and software projects. Any paid employment, internship or placement arrangement is subject to an agreed opportunity.