Senior Software Engineer · Backend & Distributed Systems

Daniel Phingston

Ernakulam, Kerala, India

Freelance

I take on freelance work. Things I can help with:

Backend services and APIs in Node.js, TypeScript or Go
Event-driven and real-time systems: RabbitMQ, Amazon SQS, MQTT, WebSockets
AWS and serverless: Lambda, DynamoDB, Docker
Offline-first web apps that keep data on the device

Email me about a project or message me on LinkedIn.

About

I build backend and distributed systems: 8+ years of network-management, IoT and cloud platforms in Node.js, TypeScript and Go, with PostgreSQL, MongoDB, Redis, RabbitMQ, Amazon SQS, AWS and Docker. I like tracing a failure through every layer (application, runtime, database, infrastructure and network) until it makes sense, then turning it into a fix that stays fixed.

Outside work I build small, local-first tools for the people around me, and play games.

Interests

Local-first software. Most of my recent projects keep data on your device and sync to storage you own, with no backend in between.
Tools for real people. A register for a clinic, a tracker for a CA doing due diligence, a calibrator for gamers.
AI, early and in the browser. A GPT-2 chatbot prototype in 2019; OCR running on WebGPU today.
Security. Responsible disclosure through HackerOne.
Debugging deep. Following one bug across routing, runtime and timeouts.

Games and inspiration

Little Fighters 2 The big inspiration. It was easy to mod, and modding it is what led me into programming.
Dark Souls Patience, pattern-reading, and getting back up at the bonfire.
Prince of Persia Rewinding time when a jump goes wrong. Still want that in production.
Dota 2 Three lanes, many towers, constant coordination.

Experience

Senior Software Engineer · Cambium Networks

08/2022 – 09/2026 · Kochi, Kerala

Built and maintained backend capabilities across cnMaestro, a multi-region network-management platform supporting device onboarding, configuration, telemetry and application workflows.
Designed reusable foundations for MarketApps and EasyApps, including configuration models, MDU and resident workflows, bulk operations, validation, database structures and migrations.
Worked across Node.js services backed by PostgreSQL, MongoDB and Redis, with RabbitMQ RPC, Amazon SQS, and long-lived WebSocket communication between managed devices and the platform.
Diagnosed a production IPv6 and IPv4 connectivity failure caused by latency-sensitive Happy Eyeballs behavior in Node.js, tracing the issue across global routing, network failures, connection attempts and application timeouts.
Designed rollback-aware orchestration for multi-step distributed operations using transaction IDs and compensating actions, reducing the risk of partially applied configuration changes.
Resolved production issues spanning device WebSocket communication, asynchronous messaging, Redis, MongoDB, PostgreSQL-backed services, migrations and automated tests.

Senior Software Engineer · Gadgeon Systems Inc

02/2020 – 08/2022 · Kakkanad, Kerala

Delivered software across multiple product teams and technology stacks, including assignments as an embedded engineer with Mavenir.
Built edge-IoT capabilities using Go, React, MQTT, SingleStore, Docker and AWS EC2.
Contributed to an edge-AI and media platform using Node.js, React, FFmpeg, Couchbase, Docker and AWS.
Developed serverless backend services using Node.js, AWS Lambda, AWS SAM, DynamoDB and CI/CD.
Built conversational and location-aware experiences using Python, Node.js, the Web Speech API and HERE Maps.

Software Developer · Suyati Technologies

07/2018 – 02/2020 · Kakkanad, Kerala

Built proofs of concept and early-stage products in a solutions team, converting new technologies and client ideas into working software.
Built a GPT-2 conversational prototype in 2019 using dialogue data extracted and processed from WhatsApp chat exports.
Developed chatbot solutions using Dialogflow, Node.js, Python, Microsoft LUIS and Microsoft Bot Framework.
Converted an offensive-security web application into a cross-platform Electron desktop application.
Helped rebuild the Momentive CMS frontend and developed an employee rewards platform using Node.js, Express, Angular and MongoDB.

Selected achievements

Production connectivity root cause analysis

Traced a latency-sensitive IPv6 and IPv4 connection failure through routing behavior, Node.js Happy Eyeballs implementation details and application timeout behavior, leading to a practical mitigation. Instead of racing IPv6 and IPv4 attempts, Node.js cancelled each attempt when a short timer fired and only then tried the next address, so on slow routes nothing ever connected.

Distributed job orchestration

Designed rollback-aware orchestration for multi-step jobs using transaction IDs and compensating actions to support safer recovery from partial failures.

Reusable platform foundations

Built shared configuration and data foundations for multiple cnMaestro applications instead of duplicating product-specific backend implementations.

Security research · HackerOne

Found and responsibly disclosed a bug that broke Cleartrip's payments. The report was validated and awarded through HackerOne.

Projects

Side projects, most of them live on GitHub Pages. Source for each is public.

Folio Resume Studio

Browser-based resume editor with reusable blocks, design presets, multiple local resumes, JSON backup, PDF export and optional Google Drive saves. No server, no build step.

JavaScript · localStorage · Playwright visual tests

Live Source
SaveKnot

Tiny local-first game-save daemon. Finds saves with the Ludusavi manifest, watches them, takes content-addressed zstd snapshots and syncs straight to your own Cloudflare R2 bucket. No account, no hosted backend.

Go · SQLite · Cloudflare R2 · Windows tray

Source
FDD Tracker

Offline PWA for financial due diligence: engagements, work papers, review points, IRLs, follow-ups, a focus timer and timesheets, with Google Drive and Calendar sync and a Gemini assistant.

React · IndexedDB · PWA · Google APIs

Live Source
Clinic Register

Offline-first outpatient register for a homeopathy clinic: patients, visits, prescriptions, appointments, billing, stock, certificates and optionally encrypted Google Drive sync.

TypeScript · IndexedDB · PWA

Live Source
Bill OCR

Turns photos of bills and receipts into structured JSON with Falcon-OCR running in the browser on WebGPU. Images never leave the device. An experimental proof of concept.

ONNX Runtime Web · WebGPU · Hugging Face

Live Source
Warzone Sens Calibrator

Finds your Warzone or Valorant mouse sensitivity from flick, tracking and micro-adjust drills, scored with Fitts throughput and a log-scale curve fit.

JavaScript · Pointer Lock · HCI maths

Live Source
Dev Env Bingo

A Memphis-pop bingo card of every way a development environment can let you down.

HTML · CSS

Live Source

Libraries and earlier work

couchbase-store
Couchbase session store for express-session.
debounce-throttle-by-key
Debounce or throttle a function separately for each key.
rabbitmq-email-publisher
Sends emails added to a RabbitMQ queue.
docker-health-check-node
Health-checks Docker services before starting, in Node.
covid-center-watch
2021: watched vaccination centres for open slots and emailed alerts (Vue + AWS Lambda).

Skills

Backend & architecture

Node.js
TypeScript
JavaScript
REST APIs
WebSockets
Distributed systems
Event-driven architecture
System design

Data & messaging

PostgreSQL
MongoDB
Redis
DynamoDB
RabbitMQ
Amazon SQS
MQTT
Database design
Database migrations

Cloud & platform

AWS
Docker
AWS Lambda
AWS SAM
Linux
CI/CD
Production troubleshooting

Additional

Go
Python
React
Angular
FFmpeg
Networking
Security
Generative AI

Education

B.Tech, Computer Science and Engineering

SCMS School of Engineering and Technology · 2014 – 2018 · Kochi, Kerala

Map

Achievements

Inventory

Daniel Phingston

Freelance

About

Interests

Games and inspiration

Experience

Senior Software Engineer · Cambium Networks

Senior Software Engineer · Gadgeon Systems Inc

Software Developer · Suyati Technologies

Selected achievements

Production connectivity root cause analysis

Distributed job orchestration

Reusable platform foundations

Security research · HackerOne

Projects

Folio Resume Studio

SaveKnot

FDD Tracker

Clinic Register

Bill OCR

Warzone Sens Calibrator

Dev Env Bingo

Libraries and earlier work

couchbase-store

debounce-throttle-by-key

rabbitmq-email-publisher

docker-health-check-node

covid-center-watch