Justine Mhar Cantado

Full Stack Engineer

I build accessible, pixel-perfect digital experiences for the web and mobile.

I started my journey in software development back in 2019, and since then, I've had the privilege of building software for a real estate tech company, sports platform, banking institution, and a ride-hailing super app.

My main focus these days is building accessible, scalable products and features at JoyRide SuperApp — from enhancing mobile applications to architecting backend services that handle millions of transactions.

I'm a problem solver at heart. Whether it's diving into a complex system integration, optimizing database queries, or crafting a smooth user experience, I love the challenge of making things work better. When I'm not coding, I explore Web3 technologies, build side projects, and write about what I learn.

Here are a few technologies I've been working with recently:

▹TypeScript
▹React / React Native
▹Node.js
▹NestJS
▹Google Cloud Platform
▹MongoDB

Journey

Full Stack Developer at JoyRide SuperApp

Feb 2024 — Present

Maintaining and scaling JoyRide's ride-hailing apps and backend services with focus on reliability, rollout safety, and real-time systems.

Architected a modular payment service integrating Xendit to speed up onboarding of new gateways
Led Cloud Functions migration to latest Node.js runtime with compatibility checks and staged rollout pipeline
Optimized backend workloads through lazy loading, Gen1 to Gen2 migration, and worker-based processing
Revamped mobile screens and flows to support new features and improve rider/driver UX
Automated CI/CD via Codemagic for safer and more consistent production releases
Built and launched revamped real-time driver location system improving accuracy and booking stability

React NativeFirebaseCloud FunctionsNode.jsCodemagicDatadog

Backend Developer at Zeniark Philippines

Jun 2022 — Oct 2023

Led backend delivery for core banking and enterprise workflows, from API design to production operations.

Delivered core banking APIs for Visa card and loan applications, fund transfers, and account services
Handled production incidents with RCA documentation and client-facing communication
Participated in CAB reviews and drove API migration from EON/IBL to APIC
Initiated NestJS services with SOLID architecture, tests, and MongoDB for user-facing products
Built SQL and shell automation scripts and internal tools for e-commerce/e-procurement operations
Integrated Business Central and DocuSign APIs to digitize and accelerate finance workflows

NestJSMySQLMongoDBShellAPICDocuSign

Career Break at Independent

Nov 2021 — May 2022

Deep dive into Web3 infrastructure and ecosystem dynamics, with hands-on experiments in NFT products, smart contracts, and campaign automation.

Explored Web3 infrastructure and blockchain systems to sharpen technical depth and product sense at ecosystem level
Designed and contributed to experimental NFT products—game mechanics and smart contracts on EVM-compatible networks—for on-chain interaction and ownership models
Built a Telegram automation tool for Web3 marketing campaigns, scaling outreach across communities with practical automation

Web3SolidityEVMTelegram APINode.js

Full Stack Developer at Assemble Sports

Mar 2021 — Nov 2021

Built full-stack sports platform capabilities with strong API integrations, testing standards, and product collaboration.

Led and integrated multiple third-party APIs for end-to-end core product capabilities
Architected scalable Vue.js frontend using reusable components and maintainable patterns
Implemented Vue.js to NestJS/Express integrations with MongoDB-backed services
Established unit, integration, and end-to-end testing strategy for release confidence
Worked with stakeholders to scope roadmap priorities and execute business-aligned deliverables

Vue.jsNestJSExpressMongoDBSentry

Software Engineer at Placester

Dec 2019 — Mar 2021

Owned and evolved legacy + modern services powering real estate platform workflows across web and mobile.

Maintained production-critical APIs and resolved incidents for openhomepro web/mobile services
Contributed across Java Servlet, NestJS, Express, and ETL services for site, account, and payment capabilities
Integrated Zuora, Airtable, Zapier, and Cognito Forms to extend platform and reduce manual workflows
Implemented and maintained unit/functional tests to improve delivery quality and regression safety
Collaborated with distributed product, DevOps, and frontend teams on feature delivery and support

Java ServletNestJSExpressETLZuora

Projects

CashPilot

Personal finance tracking app with AI-powered receipt scanning. Uses Gemini API to extract transaction details from photos and categorize expenses automatically.

Next.jsGemini APISupabase