Full Stack Developer + Mobile Developer
Seven years shipping production software — Kotlin, Compose, Flutter and React Native on mobile, React, Vue and Node on the web, deployed on AWS and GCP. I care about clean architecture, honest performance numbers, and code the next person can read.
I take products from an empty repo to something people use every day — and I'm just as happy inheriting a codebase that needs rescuing.
API, database, front end and deployment pipeline — one person accountable for the whole slice, from schema to ship.
Native Android in Kotlin and Compose, or cross-platform with Flutter and React Native — tested, instrumented, and published to the stores properly.
Crashes, jank and slow screens. I profile first, fix the real cause, then wire up monitoring so it stays fixed.
CI/CD with GitHub Actions, Bitrise and Fastlane, JUnit and Espresso suites, performance benchmarks, analytics and store compliance.
I build custom agents and skills, then synchronise and orchestrate them across Claude, OpenAI, Gemini, Grok and local models — so a small team ships like a bigger one.
Wireframes to a working screen: I design in Figma, keep a real design system, and then build it myself — no handoff gap.
I started out writing Android apps and never stopped being curious about the other half of the stack — so I learned it. Today I move comfortably between a Compose screen, a Node or Django service, and the Docker file that ships them.
Most of my career has been client and outsourcing work under NDA — high-traffic consumer platforms where crashes cost money and deadlines don't move. That taught me to profile before I refactor, to write tests that earn their keep, and to communicate in plain language with backend, design and QA.
Beyond code, I've integrated the growth side of products — Facebook Ads API and campaign tracking, Adjust attribution, Tencent SDKs for live streaming and chat — and I'm comfortable in the room: running requirement meetings with owners, PMs, product designers and QA, and merging other people's work without drama.
I'm looking for a full-time remote role where I can own real features end-to-end. If that sounds like your team, I'd love to talk.
Lead developer on a consumer mobile platform for international clients, plus the web tooling around it. I owned feature delivery end-to-end — API contracts, data layer, UI, release — and inherited a codebase that needed serious stabilising.
Built Android applications for internal business and client use, focused on API integration, UI implementation and analytics. Rebuilt older screens with modern components so they held up across device sizes.
Developed entertainment apps for foreign clients, published and maintained them in Google Play Console, and worked shoulder-to-shoulder with the API and UI/UX teams to ship on tight deadlines.
Turned mockups into responsive, production websites and stayed on for testing, debugging and maintenance — my first real stretch into the full stack.
Added features to existing Android apps and spent real effort on code quality — readable structure, testable units, fewer surprises for the next developer.
Products where I owned both ends — data model and interface. Most client platform work sits under NDA, so it's summarised further down.
Rebuilt a 77k-line PHP 5 funeral-services system (47 branches) as a type-safe Next.js 16 app. Killed SQL injection and md5 password hashing, normalised 111 tables down to 13, and cut API responses ~10x — 1187ms to 112ms.
Multi-branch stock system rewritten from PHP 7 / AdminLTE to Next.js 15 with React Server Components and Postgres. Closed six classes of security defect, cut ~85 PHP pages to 20 typed routes, and shipped it behind a CI pipeline that tests against a real database before it deploys.
School attendance built on QR codes — scan to check in, schedule attendance windows, export reports and back up records. Used daily by staff across a campus.
Parents set daily time budgets on their children's apps and websites from a web portal; a native Android app on the child's device enforces them in real time, tracks screen time and reports back. Built end to end — database, API, parent and admin portals, and the Android app.
A set of responsive marketing sites built from design mockups, then maintained: performance passes, security updates and documentation for the client's own team.
Nine consumer entertainment and fintech-style Android platforms built for international clients: multi-module architecture, live payments, real-time sockets, streaming, theming and localisation at scale. Names and screens are confidential — happy to talk through the engineering in a call.
A live multi-branch operations system running on 77k lines of procedural PHP 5 across 177 files: raw mysqli queries built by string concatenation, md5() password hashing, root database credentials hardcoded in source, no access control at all, and 111 tables — about 65 of them the same casket table copied once per city.
API responses ~10x faster, measured not estimated: /api/damayan 1187ms → 112ms, daily-performance report 963ms → 117ms, cached reference routes 543ms → 1ms. Every module exercised end-to-end against production with real writes, report totals checked arithmetically, and authorisation guards confirmed to reject privilege escalation.
A PHP 7 / AdminLTE inventory system with six nameable security defects: SQL built by string concatenation, passwords stored as plaintext varchar(50), live production credentials committed across ~20 files, admin pages 'protected' only by not being linked to, cross-branch records reachable by guessing an id, and totals recomputed differently on every page. The repository carried 13,610 files, most of it a bundled AdminLTE distribution.
All six defect classes closed and structurally prevented from returning. Repository trimmed from 13,610 files to ~90 tracked. Ships through a cheapest-first GitHub Actions pipeline — lint, typecheck, migrations and tests on a Postgres service container, build, Docker buildx, container boot smoke test — then deploys to Vercel and polls the production health endpoint before reporting success.
A high-traffic Android client app crashed frequently and slowed to a crawl at peak hours. Retention was suffering and support tickets were piling up.
Crash rate down 35%, noticeably faster loading under heavy usage, and a clear drop in customer complaints.
“Joshua greatly improved the reliability of our app. Stability went up, crashes went down, and performance became noticeably smoother.”
The client needed responsive, functional web pages fast, plus someone to keep maintaining them after launch.
Sites delivered on time, measurably better page performance, and a handover the client's own people could actually maintain.
“Joshua delivered a reliable and well-structured website. He handled development, testing and maintenance professionally.”
Several new features had to ship quickly against a fixed launch date and competitive pressure — without letting quality slip.
Features shipped ahead of schedule, development velocity up, and engagement improved after launch.
“Joshua delivered features faster than expected while maintaining high quality. Turning requirements into working features was a major asset.”
Working with Joshua has always been smooth and efficient. His understanding of Android architecture, Kotlin best practices and clean code is consistently impressive. He takes ownership, communicates clearly, and delivers stable, production-ready features on time.
One of the most reliable developers I've worked with. He approaches every task with attention to detail and a strong sense of responsibility. His expertise in Jetpack Compose, MVVM, API integration and optimisation makes him a major contributor to project success.
Joshua consistently demonstrates solid engineering and strong problem-solving. He writes clean, maintainable code and understands modern tooling deeply. Just as importantly, he collaborates well with designers, testers and backend teams.
I'm looking for a full-time remote role, and I'm open to freelance work in between. Tell me what you're building.