Birat Bhattacharjee Decorative terminal: the animated name cycles through English, Swedish, Hindi, Assamese, and Bengali once, then stays in English. Hover pauses; moving the pointer away replays. With reduced motion, only a static name is shown.

Real-time web experiences that scale.

Frontend focused full-stack developer

Gothenburg, Sweden

Dependant visa with residential and work permit (valid till Jan-2028)

What problems I solve

Frontend engineer with 6 years of experience building products where the UI carries real weight: real-time pipelines, AI interfaces, high-frequency trading tools. I've shipped an AI clinical assistant used daily by 14,000+ doctors, cut transcription latency by 80% through browser-side audio streaming, and helped a fintech maintain sub-100ms event delivery under peak load.

Most of my work sits at the intersection of performance and product velocity, making things faster for users and making the next feature easier to ship. I've gone further down the stack, building microservices in Go and Node.js and shipping cloud-native infrastructure that holds up under real load.

I collaborate closely with product and design to get from idea to production, and leave codebases a little easier to work with than I found them.

Experience

March 2024 – January 2026
Senior Full-Stack Developer — Healthplix
Bengaluru
India's largest EMR platform, serving 14,000+ doctors across 370+ cities. The work centred on HALO, an AI clinical assistant built from scoping through release. Most of the challenges here were around user experience and reliability - real-time audio pipelines, performance optimisation, and building systems that let the product team move without engineering bottlenecks.
Delivered an AI clinical assistant now used daily by 14,000+ doctors by leading frontend development of HALO from scoping through release, collaborating closely with product and design across the full lifecycle.
Reduced transcription latency by 80% (10s → 2s) by building a real-time audio streaming pipeline using WebSockets and Web Workers to process clinical audio mid-consultation.
Cut summary processing time by 60% by leveraging SSE to stream non-critical data progressively including medicine suggestions, lab reports, and conversation highlights, with a regenerate fallback.
Improved usability for doctors on low-bandwidth connections by optimising asset delivery and rendering, raising Lighthouse score from 80 → 93.
Enabled the product team to ship new clinical templates independently by designing a JSON-driven template system, reducing time-to-market from ~3 days to zero.
Unlocked onboarding of security-compliant hospitals and drove new customer acquisition by engineering a secure attachment microservice in Go handling 2,000+ RPM on AWS with MySQL and Kafka.
- React
- TypeScript
- Zustand
- WebSockets
- Node.js
- Go
- AWS
- Kafka
Related work
H.A.L.O
hplx-react-elements (npm)
hplx-feature-library (npm)
March 2022 – February 2024
Lead Full-Stack Developer — MPSC Inc.
Remote
An early-stage fintech building communication infrastructure for trading platforms. The focus was on the real-time experience end-to-end, frontend interfaces handling high-frequency interactions, backend services for conference management and payments. Reliability was the core constraint, and most of the work was about making the system predictable under load.
Unlocked onboarding of 3 enterprise clients by orchestrating scalable conferencing infrastructure on Kubernetes and SIP nodes over auto scaling groups.
Kept the real-time experience stable and predictable under peak load by implementing SSE-based event streaming with Web Workers, maintaining 30–80ms average delivery latency.
Reduced call drop rate by 25% by redesigning connection state management and reconnection flows, minimising user-facing disruptions during live trading sessions.
Secured frontend-to-backend authentication flows for both machine-to-machine and client-facing paths by integrating Auth0 with OAuth 2.0 / OIDC.
Increased licence conversion by 50% by building out frontend payment flows and integrating with backend conference management APIs.
Improved developer onboarding experience by creating Hoot.MX, a documentation tool exposing an OpenAPI Spec to promote a developer-first platform.
- React
- TypeScript
- Redux
- Kubernetes
- SSE
- Auth0
- Node.js
- AWS
Related work
HooT
June 2019 – September 2021
Software Developer - II — Hitachi Vantara
Hyderabad
A global enterprise technology company, working on internal tooling used across the organisation. The focus was on frontend quality and accessibility, making the product usable for a broader range of users, alongside backend query optimisation for manufacturing workflows.
Enabled a significantly broader user base by raising Hitachi One Dash accessibility score from 10 → 80, applying WCAG principles across the frontend.
Improved responsiveness of Hitachi One Dash by building new React components with efficient rendering strategies and integrating REST APIs with caching.
Reduced change order processing time by optimising SQL queries and writing Java code to execute queries, validate statuses, and enable live checks via multi-threading.
- React
- JavaScript
- Redux
- Java
- SQL
- REST
- WCAG

Projects

Ekko(opens in a new tab)
Open-source, end-to-end encrypted messaging platform
- Designed for horizontal scaling using stateless services and message fan-out architecture.
- Load tested at 10k concurrent users on AWS, achieving 45ms p95 latency and 100% message delivery.
- E2EE with AES-256-GCM and per-device keys; server stores only ciphertext.
Core skills
- React
- Node.js
- Express
- TypeScript
- Mongo
- AWS
- Redis
- RabbitMQ

Engineering Case Studies

Scaling UI Delivery: CI/CD for a React Design System Across Environments(opens in a new tab)
Publishing the UI library only as `latest` gave every app the same build—and one bad release a full prod blast radius. Branch pipelines, commit-driven semver, npm tags per env, and tagged installs in app builds.
- React
- Jenkins
- npm
- CI/CD
- Node.js
- Semantic versioning
From Mic to Model: Real-Time Transcription Pipelines in the Browser(opens in a new tab)
Live clinical audio transcription in the browser— reducing transcription time by ~80% (10s → 2s).
- WebSocket
- React
- TypeScript
- WaveSurfer
- AI
How we built a Secure, Real-Time Conference Events Flow for WebRTC at Scale(opens in a new tab)
Pooling multiple conference events using a single SSE stream.
- WebRTC
- React
- Microservices
- Auth0
- AWS
- FreeSWITCH
Streaming with Next.js(opens in a new tab)
App Router streaming + Suspense.
- Next.js
- React
- TypeScript

Birat Bhattacharjee Decorative terminal: the animated name cycles through English, Swedish, Hindi, Assamese, and Bengali once, then stays in English. Hover pauses; moving the pointer away replays. With reduced motion, only a static name is shown.~/name — en> _

What problems I solve

Experience

Senior Full-Stack Developer — Healthplix

Lead Full-Stack Developer — MPSC Inc.

Software Developer - II — Hitachi Vantara

Projects

Ekko(opens in a new tab)

Engineering Case Studies

Scaling UI Delivery: CI/CD for a React Design System Across Environments(opens in a new tab)

From Mic to Model: Real-Time Transcription Pipelines in the Browser(opens in a new tab)

How we built a Secure, Real-Time Conference Events Flow for WebRTC at Scale(opens in a new tab)

Streaming with Next.js(opens in a new tab)

Birat Bhattacharjee Decorative terminal: the animated name cycles through English, Swedish, Hindi, Assamese, and Bengali once, then stays in English. Hover pauses; moving the pointer away replays. With reduced motion, only a static name is shown.