00INITIALISING
MEDICAL DEVICE R&D//TAIPEI, TAIWAN//OPEN TO SENIOR ROLES

RITESH MEENA

FULL-STACK ENGINEER DEVICE → CLOUD

Nine years building connected products end to end: Zephyr firmware on the sensor, the gateway that relays it, native iOS and Android on top, the backend behind them, and the HL7 FHIR layer a hospital reads it through. One engineer, the whole path.

ACCESS WORK OPEN CHANNEL
SCROLL
01//SELECTED SYSTEMS

Fifty-five systems.
Built end to end.

Newest first. Hospital monitors reading vitals off Bluetooth at the bedside. Firmware broadcasting from the other side of that radio. The same product shipped five ways: iOS, Android, watchOS, Wear OS and WeChat. National e-wallets moving live money. And after hours, a lab of AI systems that all run locally.

Employer and client product names are partially withheld. Full names, screenshots and detail are available on request.

01 EMBEDDED 2025 — Now LIVE

AM*** BLE Gateway

Solo build

The ward-level hub. A Raspberry Pi driving an nRF52840 USB dongle in HCI mode scans and connects to multiple BLE medical devices at once and relays every measurement upstream over MQTT. Each Pi namespaces its topics by its own MAC, so any number of gateways share one broker without collision. If the configured Wi-Fi is unreachable it raises its own access point and serves a captive provisioning portal: staff can re-point it without a laptop.

Topology
Monitor → USB dongle → Pi → MQTT → app
Topics
Per-gateway namespacing, publish and subscribe
Commands
connect · scan · measure · status
Recovery
Self-hosted AP + captive config portal
Runtime
BlueZ + Python under systemd
  • Python
  • BlueZ
  • MQTT
  • nRF52840
  • Raspberry Pi
02 CLINICAL 2025 — Now LIVE

C2*** Admin Portal

Build

The web console behind the platform: hospitals, rooms, beds, devices and gateways; user and role management; alarm threshold configuration; and the reporting layer, with a distributor tier sitting above it managing multiple hospital tenants.

Manages
Hospitals · rooms · beds · devices · gateways
Controls
Users, roles, alarm thresholds, reports
Tiering
Hospital admin + distributor layers
  • Node.js
  • Express
  • JavaScript
  • MariaDB
  • Docker
03 CLINICAL 2024 — Now LIVE

Card***MULTI-BED VITALS · HOSPITAL

Lead iOS · Architecture

Clinical-grade, multi-bed vital signs monitoring for hospitals. Bedside BLE devices stream Heart Rate, Blood Pressure and MAP straight into patient records: either directly to the iPad at the bed, or relayed over MQTT by a ward gateway where a tablet per bed isn't practical. Multi-tenant SaaS: each hospital is an isolated tenant, with a distributor layer above it managing whole regions.

Capture path
Direct BLE to iPad, or gateway → MQTT
Alarms
Per-vital Warning/Critical thresholds + escalation
Encryption
Encrypted at rest and in transit
Compliance
Audit trail · e-signatures · HL7 FHIR export
Tenancy
Hospital-isolated, distributor/reseller layer
Deploy
Multi-tenant SaaS or self-hosted Compose
  • SwiftUI
  • SwiftData
  • CoreBluetooth
  • MQTT
  • Node.js
  • MariaDB
  • Docker
04 CLINICAL 2024 — Now LIVE

Vita***CLINICIAN PLATFORM

iOS Lead

The doctor's iPad app: patient lists with merged vitals pulled across services, appointments that sync into the patient's own app, prescriptions, inventory, invoicing, secure messaging and a per-doctor audit log.

Surface
iPad clinical console
Auth
JWT + 2FA on doctor login
Modules
Patients · appointments · inventory · invoices · chat
Audit
Per-doctor action log
  • SwiftUI
  • Combine
  • REST
05 CLINICAL 2024 — Now LIVE

Dr P***PATIENT COMPANION

iOS Lead · Multi-platform owner

The patient companion: not one app but five. A native iOS app, a native Android app, an Apple Watch app, a Wear OS app and a WeChat Mini Program, all speaking to the same BLE devices and the same backend. Pairs BP monitors, glucometers, SpO₂ sensors and thermometers, charts every vital's trend, and links the patient to their doctor for appointments, consults and chat. Shipped with App Store approval documentation, a full test-case suite and an ISO 13485 / EU MDR gap analysis behind it.

Devices
BP Pro
Tracks
BP · HR
Pairing
Automatic BLE, auto-sync to record
Links
Doctor connection + appointments
  • Swift
  • Kotlin
  • Jetpack Compose
  • CoreBluetooth
  • STBlueSDK
  • TypeScript
06 CLINICAL 2024 — Now LIVE

Vita*** Backend

Architecture

Three independent Express services sharing one MariaDB instance: a patient/device API, a doctor + admin portal API, and a real-time chat service. Every cross-service call carries a service key and is wrapped non-blocking with a 5-second timeout: one backend going down never cascades into the others.

Services
Three services, isolated databases
Inter-service
Authenticated, non-blocking, short timeouts
Edge
NGINX Proxy Manager, no host ports in UAT/prod
  • Node.js
  • Express
  • MariaDB
  • Docker
  • NGINX
07 AI SYSTEM 2026 PERSONAL

MIKE MyFace

Solo build

Contactless vitals from the front-facing camera. A complete rPPG pipeline written in Swift: signal extraction off live frames, bandpass DSP, peak detection, quality gating: estimating heart rate, HRV, respiration rate and pulse-wave features, with a blood pressure estimator on top and results written back into HealthKit. No sensor, no wearable, just the camera. Validated against synthetic and real signal fixtures.

Chain
rPPG → bandpass filtering → peak detection → quality gate
Outputs
HR · HRV · respiration · pulse wave · BP estimate
Validation
Morphology + real-signal tool suites
Integrates
HealthKit
Built as
SwiftUI with its own design system
  • SwiftUI
  • AVFoundation
  • Accelerate
  • HealthKit
  • rPPG
  • DSP
08 AI SYSTEM 2026 PERSONAL

LiveTranslation

Solo build

Self-hosted live event translation. A speaker talks; the system transcribes, translates into many languages at once, and delivers captions to a venue screen, to attendees' phones, and as synthetic interpreter audio. Every model runs locally: no cloud APIs, no per-minute billing, no audio leaving the building. Deliberately cascaded rather than end-to-end, so models swap freely, an event glossary can be injected, and a language is added without retraining anything.

Speech
faster-whisper with voice-activity gating
Latency
Low enough for live captioning on CPU alone: no GPU
Translation
NLLB and MADLAD, many languages in parallel
Surfaces
operator · screen · viewer · portal
Design
Cascaded: capture, recognise, translate, deliver
  • Python
  • faster-whisper
  • NLLB
  • Piper TTS
  • WebSockets
09 AI SYSTEM 2026 PERSONAL

AI-BROKER

Solo build

A self-hosted signal system for the Indian market running entirely on free data. It analyses NSE stocks and indices and produces calls for four styles (swing, intraday, long-term and F&O), each with entry, stop-loss, target, position size, confidence and a plain-English reason, on a local web dashboard. The model trains locally and is validated for honesty against its own backtests.

Styles
Swing · Intraday · Long-term · F&O
Per signal
Entry · SL · target · size · confidence · reasoning
Modules
Ingest, signalling, backtesting, journalling, API
Data
100% free sources, fully self-hosted
Scope
Personal and educational: not investment advice
  • Python
  • Pandas
  • scikit-learn
  • FastAPI
10 AI SYSTEM 2026 BUILT

Grok Outreach Agent

Solo build

CRM, lead generation, multi-channel outreach and meeting booking for marketing agencies. Lead discovery across Maps, startups and DTC sources; a pluggable AI brain (hosted, or fully local through Ollama); day 0→1→3→7→14 sequences with a background worker; an inbox that scores reply sentiment and intent and hands off to sales; A/B testing on subjects and CTAs. Runs fully in demo mode with no API keys at all.

AI brain
Provider-agnostic: hosted or local via Ollama
Channels
Email · WhatsApp Cloud API · LinkedIn/X
Sequences
Multi-touch flows with worker + A/B testing
Booking
Calendly · Cal.com · Google Calendar
Degrades to
Full demo mode, zero keys required
  • Next.js
  • Supabase
  • TypeScript
  • Ollama
  • OAuth
11 AI SYSTEM 2026 PERSONAL

MarketMind: Mike CMO

Solo build

A local-first AI Chief Marketing Officer. Ten specialised marketing agents analyse a brand, find opportunities and draft content across every channel, powered entirely by a local model through Ollama: private, unlimited, and with no API bills.

Agents
10 specialised marketing roles
Runtime
Ollama, fully local
Cost
No API bills, unlimited runs
  • Node.js
  • Ollama
  • Agent orchestration
12 AI SYSTEM 2026 BUILT

Mike News Network

Solo build

A live Mike news broadcast: an AI anchor reads stories continuously in a BBC-style broadcast UI, auto-fetching fresh headlines every three minutes. Ships with one-command setup and start scripts for both macOS and Windows.

Cadence
New stories pulled every 3 minutes
Presentation
BBC-style continuous broadcast UI
Packaging
One-command setup, macOS + Windows
  • Python
  • React
  • TTS
  • News APIs
13 AI SYSTEM 2026 PERSONAL

Mike Movie

Solo build

An end-to-end generative film pipeline: backend generation service, a frontend for directing it, and a scoring stage for music. Now on its third architecture revision after two working builds.

Revision
V3, after two working builds
Parts
Backend generation · frontend director · scoring
Stage
Music scoring added last
  • Python
  • Generative video
  • React
14 AI SYSTEM 2026 PERSONAL

Movie Story-Teller

Solo build

Turns a movie plus its subtitle file into a narrated Hindi recap, then slices that into upload-ready YouTube Shorts: script generation, TTS narration, cutting and rendering, driven from a local web UI and fully reproducible in Docker. Already run across a shelf of features.

Flow
Subtitles → script → narration → cut → Shorts
Interface
One command, then a local web UI
Output
Vertical, upload-ready
  • Python
  • FFmpeg
  • TTS
  • Docker
15 AI SYSTEM 2026 PERSONAL

YT Automation

Solo build

A scheduled multi-channel YouTube publishing pipeline: assembles video from images and music, manages per-channel credentials and configuration, and uploads on a cron-driven schedule from a container.

Assembles
Video from images + music tracks
Scheduling
Cron-driven, per-channel credentials
Runtime
Containerised
  • Python
  • YouTube Data API
  • Docker
16 PLATFORM 2026 BUILT

MyVyapr

Solo build

A website-builder SaaS for small businesses, split into three deployable pieces: a Next.js marketing site, a Fastify + Prisma + Postgres API handling auth, template parsing, site content and publishing, and a Vite + React product app with signup, dashboard and an inline editor. Published sites are served per-subdomain. Every value comes from env: no hardcoded fallbacks anywhere in the stack.

Marketing
Next.js
Product
Vite + React dashboard + inline editor
API
Fastify + Prisma + Postgres
Publishing
Per-subdomain served sites
Deploy
Full stack via Docker Compose
  • Next.js
  • React
  • Fastify
  • Prisma
  • Postgres
  • Docker
17 PLATFORM 2026 BUILT

FuelPro Manager

Solo build

A complete offline-first management system for Indian fuel stations: station setup wizard, pump configuration, day operations, shift and sales handling, an admin panel and AI-assisted analytics. Three surfaces off one codebase: a browser app that needs no server after first load, a React Native mobile build for iOS and Android, and a Node server for the deployments that want one.

Surfaces
Browser · React Native (iOS + Android) · Node server
Model
Offline-first: no internet needed after first load
Covers
Pumps · shifts · sales · admin · analytics
Deploy
Dev / UAT / prod Compose profiles, NGINX-served
  • React Native
  • JavaScript
  • Node.js
  • IndexedDB
  • Docker
  • NGINX
18 PLATFORM 2026 BUILT

Meena Group

Solo build

A multi-page corporate site spanning technology, energy, AI services, portfolio, careers and news: hand-built, containerised behind NGINX and deployed with Docker Compose.

Pages
Technology · energy · AI services · portfolio · careers · news
Serving
NGINX in Docker Compose
Build
Hand-written, no framework
  • HTML
  • CSS
  • JavaScript
  • NGINX
  • Docker
19 PLATFORM 2026 BUILT

Rivi*** Beauty Spa

Solo build

A containerised marketing site with a swappable image-slot system so the client can change photography without touching markup, plus proper sitemap and robots handling for search.

Content
Drop-in image slots, no markup edits
SEO
Sitemap + robots handled
Deploy
NGINX container
  • HTML
  • JavaScript
  • NGINX
  • Docker
20 TOOL 2026 PERSONAL

MikeMacClean

Solo build

A native macOS cleaner in the spirit of CleanMyMac: one Smart Scan across Cleanup, Privacy, Protection and Speed with a single Clean button and a per-area breakdown you can drill into, ten cleanup and inspection modules, and a menu-bar panel for one-tap memory and junk relief. Swift 5.9 and SwiftUI with zero third-party dependencies.

Finds
Xcode derived data · device support · npm/pip/brew/CocoaPods caches
Also
Broken preferences · stale saved state · unused simulators · Docker disk images
Surfaces
Full window + menu-bar quick panel
Dependencies
None: pure Swift/SwiftUI
  • Swift 5.9
  • SwiftUI
  • AppKit
  • SwiftPM
21 TOOL 2026 PERSONAL

Mike-ADB

Solo build

An iOS ad blocker built the hard way: a NetworkExtension packet tunnel that parses DNS itself and answers queries against a local blocklist store using a hashed store for constant-time lookup, paired with a Safari content-blocker extension and a CoreData-backed whitelist. Onboarding, VPN management and extension status all handled in-app.

Tunnel
NetworkExtension DNS interception, own DNS parser
Lookup
Hashed blocklist store, constant-time lookup
Second layer
Safari content blocker extension
State
CoreData whitelist + seeded blocklists
  • Swift
  • NetworkExtension
  • SafariServices
  • CoreData
22 TOOL 2026 PERSONAL

macOS Ad Blocker

Solo build

Two layers of blocking on one Mac: a system-wide DNS sinkhole intercepting every query before it leaves the machine (so Safari, Chrome, Firefox and Spotify are all covered), plus a Chrome extension for what DNS can't reach, like YouTube ads, element hiding and anti-adblock nag removal.

Scale
1,000,000+ ad, tracker and malware domains
Layer 1
System-wide DNS sinkhole
Layer 2
Chrome extension with per-site pause
Reaches
Every app, not just browsers
  • Shell
  • dnsmasq
  • Chrome MV3
23 TOOL 2026 PERSONAL

Mike Downloader

Solo build

A Chrome extension that catches video on any site (through network requests, XHR and fetch hooks, and DOM scanning), then downloads it. HLS streams are fetched segment by segment and stitched in-browser with decryption support, with a quality picker for master playlists and a one-click FFmpeg command for when local is faster.

Detects
HLS (.m3u8) · DASH · MP4 · audio
Decrypts
Encrypted HLS segments, in-browser
Manifest
V3, live popup list + settings page
Escape hatch
One-click FFmpeg command
  • JavaScript
  • Chrome MV3
  • HLS
  • Web Crypto
24 TOOL 2026 PERSONAL

Mike Music

Solo build

A YouTube Music–style player for iOS that plays audio and video from your own files and pulls audio or video straight from a YouTube link: entirely on device, with no server and no third-party dependencies. Project generated with XcodeGen.

Targets
iOS 17+, iOS 26 mini-player API when available
Model
Fully on-device, no backend
Project
Generated with XcodeGen
  • Swift
  • SwiftUI
  • AVFoundation
  • XcodeGen
25 CLINICAL 2026 TESTED

Dr P*** Android

Solo build

The native Android half of the patient app, written from scratch in Kotlin with Jetpack Compose: the same BLE device pairing, vitals history and doctor connection as the iOS app, plus an OTA test harness for pushing firmware to the device from the phone. Signed off as fully tested in August 2026.

Build
Modern minSdk, debug and release variants
UI
Jetpack Compose
Tooling
Gradle Kotlin DSL
Extra
Firmware OTA update harness
Status
Fully tested and signed off
  • Kotlin
  • Jetpack Compose
  • Android BLE
  • Gradle KTS
26 CLINICAL 2026 BUILT

Dr P*** Mini Program

Solo build

A WeChat Mini Program bringing the patient app to the platform most of the China-market user base already lives in: TypeScript, the full device command set verified working, no app install required.

Platform
WeChat Mini Program
Language
TypeScript
Coverage
All device commands verified
  • TypeScript
  • WeChat MP
  • BLE
27 EMBEDDED 2026 BUILT

MQTT Platform

Solo build

A self-contained MQTT stack (broker and a web frontend for watching topics and traffic live), brought up with one Compose file so a gateway can be developed and debugged without any hospital infrastructure in the loop.

Parts
Broker + web frontend
Purpose
Local gateway development and topic inspection
Deploy
Single docker-compose bring-up
  • MQTT
  • Mosquitto
  • JavaScript
  • Docker
28 EMBEDDED 2026 TESTED

RF Test App

Solo build

A native iOS harness for RF and radio-side bring-up on the device programme: used to exercise and confirm behaviour during hardware testing rounds.

Platform
iOS, native Xcode project
Use
Hardware bring-up and RF verification
  • Swift
  • CoreBluetooth
29 PLATFORM 2026 BUILT

RBS*** Malaysia

Solo build

A second containerised marketing site on the same swappable image-slot system as the wellness site: the client changes photography without touching markup, and it deploys behind NGINX with Cloudflare in front.

Content
Drop-in image slots
Edge
Cloudflare + NGINX container
  • HTML
  • JavaScript
  • NGINX
  • Docker
  • Cloudflare
30 TOOL 2026 PERSONAL

Music Player

Solo build

The first pass at the music project: a native Xcode player alongside a Python companion for library handling, which became the groundwork for Mike Music.

Parts
Xcode app + Python library tooling
Became
Groundwork for Mike Music
  • Swift
  • Python
  • AVFoundation
31 CLINICAL 2025 — 2026 BUILT

Dr P*** Watch

Solo build

A watchOS companion that talks to the device directly rather than proxying through the phone: its own BLE packet parser, CRC16 integrity checking and AES helper for the encrypted payload, with readings written straight into HealthKit. Ships with an App Clip variant so a device can be onboarded at the point of care without a full install.

Targets
watchOS app + App Clip
Shows
Latest readings · health alerts
Sync
WatchConnectivity to phone
  • SwiftUI
  • watchOS
  • CoreBluetooth
  • CoreData
  • HealthKit
  • App Clip
32 CLINICAL 2025 — 2026 ONGOING

FDA / SaMD Regulatory Package

Software lead

The documentation spine a medical device needs to reach market: software validation procedure, development plan, SRS, architecture and design specs, a design/requirements trace matrix, risk management plan and report, and verification protocols: alongside a cybersecurity work instruction aligned to FDA premarket software guidance and IMDRF SaMD risk framing.

Covers
SYS-044 software validation · WI-007 cybersecurity
Artefacts
SDP · SRS · SAS · SDS · trace matrix · risk report
Frameworks
FDA premarket software · IMDRF SaMD · GMLP
Quality system
ISO 13485:2016 vs EU MDR gap analysis
  • IEC 62304
  • ISO 14971
  • ISO 13485
  • EU MDR
  • FDA eSTAR
  • IMDRF
33 TOOL 2025 — 2026 PERSONAL

Load & Resilience Suite

Solo build

A scripted toolkit for testing my own infrastructure's limits: recon and scanning passes, heavy-load and packet-flood drivers, slow-attack simulation, and a core monitoring script that watches the host while each run happens, so the failure mode is observed rather than guessed.

Load
Apache Bench · wrk · curl drivers
Resilience
SlowHTTPTest · packet flood · disk pressure
Observability
Core monitoring alongside every run
Scope
My own servers only, authorised testing
  • Bash
  • wrk
  • ab
  • SlowHTTPTest
34 CLINICAL 2025 BUILT

Accu*** FHIR Gateway

Architecture · Build

An HL7 FHIR R4 gateway that normalises proprietary device measurements into standards-compliant FHIR resources any hospital EMR can consume. A Turborepo monorepo (FHIR gateway, admin API, admin portal and landing site) with Keycloak handling identity and the whole stack reproducible across local, UAT and production Compose files.

Endpoint
FHIR R4 compliant resource API
Identity
Keycloak (OAuth2 / OIDC)
Apps
gateway · admin-api · admin-portal · landing
Packages
fhir-normalizer · db
Environments
local · UAT · prod, all containerised
  • TypeScript
  • Turborepo
  • HL7 FHIR R4
  • Keycloak
  • Docker
  • Postgres
35 CLINICAL 2025 BUILT

Accu*** Product Site

Build

Product site for a blood pressure monitoring device: Next.js 14 App Router with standalone output, multi-stage Docker image running as a non-root user, behind NGINX Proxy Manager for SSL and routing.

Framework
Next.js 14 · React 18 · Tailwind
Container
Multi-stage image, non-root runner
Edge
NGINX Proxy Manager for SSL + routing
  • Next.js 14
  • React
  • Tailwind
  • Docker
36 EMBEDDED 2025 BUILT

Gateway Control Plane

Solo build

A dockerised control plane for a third-party BLE Wi-Fi gateway: browser UI plus backend API, with its own Mosquitto broker and a bridge server translating between HTTP and the gateway's MQTT command surface. Environment-first: nothing hardcoded, every secret comes from env templates.

Parts
HTTP-to-MQTT bridge, broker and web UI
Device
Third-party BLE Wi-Fi gateway
Config
Strict env-first, no fallback defaults
Deploy
Docker Compose
  • Node.js
  • MQTT
  • Mosquitto
  • Docker
37 EMBEDDED 2025 BUILT

BLE Vitals Broadcaster

Firmware + iOS

Vitals over BLE advertising with no connection and no pairing at all. Zephyr firmware on an nRF52840 dongle broadcasts a custom 8-byte blood-pressure payload every two seconds; an iPad app scans for it, validates the company ID and message type, de-duplicates by sequence number per physical radio, and persists each reading: surviving backgrounding through CoreBluetooth state restoration.

Wire format
Compact fixed-size advertisement payload
Service UUID
Standard SIG UUID, so iOS can filter in background
Toolchain
nRF Connect SDK with the Zephyr toolchain
Dedupe
De-duplicated per physical radio
Swappable
Source abstraction: simulated now, real device later
  • Zephyr RTOS
  • C
  • nRF52840
  • SwiftUI
  • SwiftData
38 EMBEDDED 2025 TESTED

Accu*** Monitor Firmware

Firmware + validation

BLE firmware for a vitals monitor on an STM32WB55: six measured parameters over a pairing-free link, with a companion API-check harness used to verify every command and response against the app before release.

MCU
STM32WB55
Parameters
6 vitals over BLE, no pairing required
Verification
Command-verification harness, app-in-the-loop
  • STM32WB55
  • C
  • BLE GATT
39 EMBEDDED 2025 BUILT

CL*** Onboarding & BLE Architecture

Architecture · iOS

Secure device onboarding for the wearable: the full architecture from NFC tap through BLE handshake to authenticated session, with defined LED state machines so a user can read device status off the hardware itself. Delivered twice over: an iOS app with an App Clip and a paired watch app, and a three-module Android build sharing a common core between phone and Wear OS.

Onboarding
NFC tap → secure BLE handshake → session
Feedback
Defined LED state machine, v1 and v2
Apple
iOS app + App Clip + watch app
Android
core / mobile / wear, shared module
NFC
ST25 tag stack, CoreNFC demo harness
  • Swift
  • Kotlin
  • CoreBluetooth
  • CoreNFC
  • ST25
  • Wear OS
  • App Clip
40 EMBEDDED 2025 TESTED

BLE Command Harness

Solo build

A cross-platform test harness for iOS and Android that exercises every BLE command and API on a device under test, so firmware and app behaviour can be verified against each other before either ships.

Platforms
iOS + Android, matched command sets
Purpose
Verify firmware ↔ app before either ships
Covers
Every BLE command and API response
  • Swift
  • Kotlin
  • CoreBluetooth
  • Android BLE
41 EMBEDDED 2025 BUILT

BLE iPad Monitor

Solo build

An earlier iPad monitoring client built on UIKit and CoreData with its own BLE response model: the groundwork that the SwiftUI/SwiftData generation of the hospital apps was designed against.

Persistence
CoreData persistence model
Layer
Typed BLE response model
Role
Reference client for later SwiftUI builds
  • Swift
  • UIKit
  • CoreBluetooth
  • CoreData
42 FINTECH 2021 SHIPPED

UDA E***

Architecture · UI

A no-fuss cashless payment app built around a fraud detection system and PCI-DSS compliance, so every transaction stays safeguarded end to end.

Platform
iOS · iPhone
Market
Malaysia
Security
Fraud detection · PCI-DSS
  • Swift
  • RESTKit
  • FCM
43 FINTECH 2018 — 2021 SHIPPED

Za***

Architecture · Caching · UI

Messaging and an e-wallet in one: the easiest way for locals and foreigners in Malaysia to transfer money inside a chat and pay for anything at their fingertips, skipping the trip to a physical store entirely.

Market
Malaysia, consumer scale
Rails
QR · wallet transfer · merchant checkout
Model
Chat and wallet in one surface
My role
Architecture, caching layer, UI, delivery
  • Swift
  • Objective-C
  • QR
  • FCM
  • RESTKit
44 FINTECH 2020 SHIPPED

AXA***

Architecture · UI

Mobile payments across more than a thousand participating merchants and utility providers, with several online payment methods so users and merchants can transact whichever way suits them.

Reach
1,000+ merchants and utility providers
Platform
iOS · iPhone
Security
Fraud detection · PCI-DSS
  • Swift
  • Objective-C
  • FCM
45 FINTECH 2020 SHIPPED

Pay***

Architecture · UI

Cashless payments with fraud detection and PCI-DSS compliance across the full transaction path.

Platform
iOS · iPhone
Market
Malaysia
Security
Fraud detection · PCI-DSS
  • Swift
  • Objective-C
  • FCM
46 FINTECH 2019 SHIPPED

WeP***

Client comms · Build

Merchant-side mobility: the tools a business needs to run its daily transactions inside a secured, encrypted environment.

Platform
iOS · iPhone
Audience
Merchants
Security
Encrypted transaction env
  • Swift
  • Objective-C
  • GoogleKit
47 FINTECH 2019 SHIPPED

Pay4***

Architecture · UI

An alternative card-based way to service loans: housing, car, credit card, personal, motorcycle and PTPTN repayments from a single app.

Platform
iOS · iPhone
Covers
Housing · car · credit card · personal · PTPTN
Market
Malaysia
  • Swift
  • Objective-C
  • FCM
48 PLATFORM 2019 BUILT

Qubi*** Tech Systems

Build

A corporate services site covering managed application services and support: an earlier web build kept in the archive.

Covers
Managed application services + support
Era
Earlier web build, archived
  • PHP
  • HTML
  • CSS
49 MOBILITY 2017 — 2019 SHIPPED

MU***

Both apps, end to end

A two-sided ride-hailing platform for Australia. Riders request nearby drivers; drivers accept or reject in real time. I built both apps end to end (live location and mapping architecture, the matching flow, caching and UI), working directly with the client on scope.

Apps
MUVE rider + MUVE driver (formerly Roooz)
Payments
PayPal checkout
Location
Live tracking · geofencing · routing
  • Swift
  • Objective-C
  • GoogleKit
  • PayPal
  • RESTKit
50 FINTECH 2018 SHIPPED

UPa***

Architecture · UI

Pick a merchant or payee account and the service pays on your behalf immediately: errands settled from the phone for a flat minimum charge.

Platform
iOS · iPhone
Model
Pay-on-behalf, flat service charge
Market
Malaysia
  • Swift
  • Objective-C
  • FCM
51 MOBILITY 2018 SHIPPED

AT*** Travel Service Centre

Architecture · UI

Flight booking in a minute or two: a redesigned navigation and simplified booking flow that extended an operator's airline kiosks onto iPhone.

Platform
iOS · iPhone
Client
Airline booking, via kiosk operator
Focus
Simplified booking flow
  • Objective-C
  • QR
  • RESTKit
52 MOBILITY 2018 SHIPPED

Pok***

Architecture · UI

Browse and buy Pokka's juices, milk, teas and coffees in-app, checking out straight through the operator's payment gateway.

Platform
iOS · iPhone
Checkout
Operator payment gateway
Region
Malaysia · Singapore
  • Swift
  • Objective-C
  • QR
  • FCM
53 MOBILITY 2017 SHIPPED

MU*** Driver

Solo build

The driver console for MUVE: accept, reject and complete ride requests in real time with live navigation.

Platform
iOS · iPhone
Region
Australia
Real time
Accept / reject / navigate
  • Swift
  • Objective-C
  • GoogleKit
54 MOBILITY 2017 SHIPPED

Amer*** Ontime: Rider

Client comms · Build

Rider app for the US taxi market: request a nearby driver, watch the trip and pay in app.

Platform
iOS: rider + driver
Region
United States
Core
Dispatch · live matching · navigation
  • Swift
  • Objective-C
  • GoogleKit
  • RESTKit
55 MOBILITY 2017 SHIPPED

Amer*** Ontime: Driver

Client comms · Build

Driver console for the same platform: accept or reject requests in real time, with dispatch and in-app navigation.

Platform
iOS: rider + driver
Region
United States
Core
Dispatch · live matching · navigation
  • Swift
  • Objective-C
  • GoogleKit
  • RESTKit
02//PROFILE

I build the layer
other teams rely on.

I'm a full-stack engineer in Taipei, building regulated medical device software for a medical technology manufacturer. Full-stack in the literal sense: I write the firmware on the sensor, the gateway that carries its data, the iOS and Android apps that read it, the backend that stores it and the FHIR layer a hospital consumes it through. Before Taiwan I spent seven years in Kuala Lumpur leading iOS at a fintech and payments group, shipping wallets a lot of Malaysia used daily. My work sits where careful engineering actually matters: money moving between strangers, vitals arriving from a device at a hospital bedside.

On the medical side I own more than the app. I've written the Zephyr firmware that broadcasts a reading, the Raspberry Pi gateway that relays it over MQTT, the FHIR layer that normalises it for a hospital EMR, and the IEC 62304 documentation that lets any of it reach a regulated market. The patient app alone ships on five platforms (iOS, Android, Apple Watch, Wear OS and WeChat), and I build the native ones myself, Kotlin and Jetpack Compose as readily as Swift.

Nights and weekends I keep a lab running: an rPPG app that reads a pulse off the front camera, a fully local live-translation stack, a self-hosted market signal system, a native macOS cleaner, an iOS ad blocker with its own DNS parser. Building things end to end is how I stay sharp.

Before all of it: a competitive gymnast through 2010, into the final round of the Junior State Gymnastic Championship. It taught me what engineering keeps asking for: repeat the hard thing until it's clean.

BASEDTaipei, Taiwan
ROLEFull-Stack Engineer · Medical Devices
EDUCATIONMCA: JECRC University, Jaipur
DOMAINSMedical devices · Fintech · AI
DEPTHFirmware → gateway → app → backend
REACHiOS · Android · watchOS · Wear OS · web
LANGUAGESEnglish · Hindi

Confident, self-motivated, optimistic.

// the three words on my CV that have actually held up
03//TIMELINE

Nine years, one craft.

  1. JAN 2025PRESENT

    Full-Stack EngineerMedical Device Manufacturer

    CURRENT
    Taipei, Taiwan
    • Own the mobile and device software for a regulated blood-pressure monitoring platform and its patient-facing app family.
    • Ship the same product natively across five platforms: iOS, Android, Apple Watch, Wear OS and WeChat.
    • Work the full depth of a connected device: Zephyr and STM32 firmware, Raspberry Pi BLE gateways over MQTT, backend services, and the HL7 FHIR layer hospitals consume.
    • Author the regulatory software spine: IEC 62304 validation, ISO 14971 risk management, and the FDA premarket cybersecurity package.
    SwiftKotlinZephyr RTOSMQTTHL7 FHIRIEC 62304
  2. 2024PRESENT

    Independent ConsultantMobile & Systems

    PARALLEL
    Remote · India & Malaysia clients
    • Design and build complete products for small businesses and founders, end to end rather than as a pair of hands on someone else's codebase.
    • Delivered a CRM and multi-channel outreach platform, a website-builder SaaS, an offline-first fuel-station management system, and a set of containerised business sites.
    • Run each one the whole way: architecture, build, Docker deployment behind NGINX, and handover documentation the client can act on.
    Next.jsReact NativeFastifyPostgresDockerOllama
  3. NOV 2017DEC 2024

    Sr. iOS DeveloperFintech & Payments Group

    Kuala Lumpur, Malaysia
    • Led and managed the iOS team across seven years: architecture decisions, code review, mentoring.
    • Shipped and maintained a portfolio of national payment wallets: Zapp, AXAPay, UDA EZPay, Pay4U, UPayMe, PayRW and WePayU.
    • Owned the full mobile lifecycle: build, patch, TestFlight and App Store release management.
    • Worked to PCI-DSS requirements with fraud detection across every transaction path.
    SwiftObjective-CPCI-DSSFirebaseJenkinsJIRA
  4. NOV 2016NOV 2017

    iOS DeveloperSoftware Services Company

    Jaipur, India
    • Built two-sided ride-hailing platforms for the Australian and US markets, rider and driver apps both.
    • Worked directly with clients and UX designers to define, design and ship features.
    • Identified and fixed bottlenecks; ran system testing against user requirements.
    • Authored technical documents, user guides and support documentation.
    SwiftObjective-CGoogleKitPayPalGeofencing
  5. JAN 2016JUN 2016

    iOS Developer, InternshipSoftware Services Firm

    India
    • Full lifecycle participation: coding, testing and release activities under agile.
  6. 20112016

    EducationMCA & BCA

    Rajasthan, India
    • Master of Computer Application: JECRC University, Jaipur (2014–2016).
    • Bachelor of Computer Application: MDS University, Ajmer (2011–2014).
04//CAPABILITY

The whole path,
sensor to screen.

L1

Silicon & Radio

Zephyr RTOS firmware on nRF52840 and STM32WB55: advertising payload design, GATT services, pairing-free links, and the validation harnesses that prove them.

  • Zephyr RTOS
  • nRF Connect SDK
  • STM32WB55
  • C
  • BLE GATT
L2

Gateway & Transport

Raspberry Pi gateways on BlueZ relaying device data over MQTT with per-gateway topic namespacing, captive-portal Wi-Fi recovery, and dockerised control planes.

  • Python
  • BlueZ
  • MQTT
  • Mosquitto
  • systemd
L3

Native Mobile

Swift, SwiftUI, Objective-C and UIKit on Apple; Kotlin and Jetpack Compose on Android and Wear OS. CoreBluetooth and Android BLE, background state restoration, App Clips, custom UI and animation: the same product, natively, on every platform it needs to reach.

  • Swift
  • SwiftUI
  • Kotlin
  • Jetpack Compose
  • Objective-C
  • watchOS
  • Wear OS
L4

Signal & Vision

rPPG pipelines over live camera frames: bandpass DSP, peak detection, HRV and respiration analysis, and quality gating so nothing unreliable ever reaches the user.

  • AVFoundation
  • Accelerate
  • rPPG
  • DSP
  • HealthKit
L5

Backend & Data

Node and Express service meshes with keyed, non-blocking inter-service calls; Fastify and Prisma over Postgres; MariaDB schemas; everything containerised behind NGINX.

  • Node.js
  • Express
  • Fastify
  • Postgres
  • MariaDB
  • Docker
L6

Interop & Compliance

HL7 FHIR R4 normalisation behind Keycloak identity, AES-256-GCM PHI encryption, audit trails and e-signatures, and the IEC 62304 / ISO 14971 paperwork that carries it through review.

  • HL7 FHIR R4
  • Keycloak
  • IEC 62304
  • ISO 14971
  • PCI-DSS
L7

Applied AI

Local-first AI systems: cascaded ASR→MT→TTS pipelines, agent orchestration over Ollama and OpenAI-compatible endpoints, and locally trained signal models validated against their own backtests.

  • faster-whisper
  • NLLB / MADLAD
  • Ollama
  • scikit-learn
  • FastAPI
L8

Delivery

MVC, MVP and MVVM in real codebases, with the release discipline around them: Jenkins, JIRA, Confluence, TestFlight, App Store review, and multi-environment Compose profiles.

  • MVVM
  • Jenkins
  • JIRA
  • TestFlight
  • NGINX
05//TOOLBOX

Everything I actually
reach for.

A hundred and seventy-four entries across thirteen groups: languages, frameworks, radios, infrastructure, standards and the software I work in daily. A filled marker means it's a daily driver rather than something I've used and can pick back up.

Daily driver Working knowledge
01

Languages

13
  • Swift
  • Kotlin
  • Objective-C
  • C
  • Python
  • JavaScript
  • TypeScript
  • Dart
  • PHP
  • SQL
  • Bash
  • HTML
  • CSS
02

Apple Frameworks

18
  • SwiftUI
  • UIKit
  • Cocoa Touch
  • AppKit
  • Combine
  • CoreData
  • SwiftData
  • CoreBluetooth
  • CoreNFC
  • AVFoundation
  • Accelerate
  • HealthKit
  • MapKit
  • WatchConnectivity
  • NetworkExtension
  • SafariServices
  • App Clips
  • Swift Package Manager
03

Android & Cross-Platform

10
  • Android SDK
  • Jetpack Compose
  • Android BLE
  • Wear OS
  • Gradle / KTS
  • Android Studio
  • Multi-module builds
  • React Native
  • Flutter
  • WeChat Mini Program
04

Embedded & Radio

19
  • Zephyr RTOS
  • nRF Connect SDK
  • nRF52840
  • nRF52832
  • STM32WB55
  • STBlueSDK
  • ST25 NFC
  • BLE GATT
  • BLE Advertising
  • BlueZ
  • HCI
  • OTA / DFU
  • CRC16
  • MQTT
  • Mosquitto
  • Raspberry Pi
  • J-Link
  • nRF Connect Programmer
  • west / CMake
05

Backend & Web

16
  • Node.js
  • Express
  • Fastify
  • Prisma
  • Next.js
  • React
  • Vite
  • Tailwind CSS
  • FastAPI
  • Laravel
  • REST
  • WebSockets
  • JWT
  • OAuth2 / OIDC
  • Keycloak
  • Turborepo
06

Data & Storage

10
  • MariaDB
  • MySQL
  • PostgreSQL
  • SQLite
  • CoreData
  • SwiftData
  • Supabase
  • IndexedDB
  • Keychain
  • Schema migrations
07

AI & Signal

15
  • rPPG
  • DSP / bandpass
  • Peak detection
  • HRV analysis
  • faster-whisper
  • Silero VAD
  • NLLB
  • MADLAD
  • Piper TTS
  • Ollama
  • OpenAI-compatible APIs
  • scikit-learn
  • Pandas
  • NumPy
  • FFmpeg
08

Infrastructure & DevOps

12
  • Docker
  • Docker Compose
  • NGINX
  • NGINX Proxy Manager
  • Cloudflare
  • Jenkins
  • Git
  • systemd
  • Cron
  • Multi-env deploys
  • Captive portal / AP mode
  • SSL renewal
09

Tooling & Software

17
  • Xcode
  • Android Studio
  • Instruments
  • XcodeGen
  • CocoaPods
  • TestFlight
  • App Store Connect
  • Google Play Console
  • JIRA
  • Confluence
  • Postman
  • Burp Suite
  • Adobe Illustrator
  • Photoshop
  • Moqups
  • VS Code
  • Claude Code
10

Standards & Compliance

12
  • HL7 FHIR R4
  • IEC 62304
  • ISO 14971
  • ISO 13485:2016
  • EU MDR
  • FDA premarket software
  • IMDRF SaMD
  • GMLP
  • PCI-DSS
  • AES-256-GCM
  • TLS / HTTPS
  • Audit trail & e-signature
11

Architecture & Practice

13
  • MVVM
  • MVC
  • MVP
  • Agile / Scrum
  • Code review
  • Unit testing
  • Test case authoring
  • Caching strategy
  • Offline-first
  • Multi-tenancy
  • Release management
  • Technical writing
  • Team leadership
12

Security & Resilience

09
  • Apache Bench
  • wrk
  • SlowHTTPTest
  • hping3
  • Load profiling
  • DNS sinkholing
  • Packet tunnelling
  • Payload encryption
  • Secrets hygiene
13

Platforms Shipped To

10
  • iOS / iPhone
  • iPadOS
  • watchOS
  • Android
  • Wear OS
  • macOS
  • WeChat
  • Web
  • Raspberry Pi / Linux
  • Embedded MCU
06//CONTACT

Open channel.

Open to senior, lead and staff engineering roles, and to serious work at the edge of hardware and health. Email reaches me fastest.

[rkaydoc@gmail.com]
LINKEDINhelloriteshhere