Biswajeet Das

Experience

1. Product Engineer (Lead) · Lightwork AI (Remote)

   June 2025 - Present
   • Architected and am leading a zero-trust security model across all microservices: each request carries a signed JWT, verified via JWKS, that downstream services authorize independently. A cross-team initiative spanning the data, AI, and DevOps teams, owned end to end from ADR and technical spec to design presentations.
   • Built the realtime WebSocket layer end to end, backend and frontend: the NestJS gateway and the client that consumes it.
   • Built backend services across the NestJS microservices stack: TCP transport between services, Google Pub/Sub events, Postgres and MongoDB, and Better Auth.
   • Integrated voice AI agents to handle live calls, building the API and call-handling layer around the LLM.
   • Co-led the migration from a legacy React Router app to a modern Next.js stack with Tailwind and shadcn.
   • Owned features end to end, from scoping through API to UI; set up feature flags and PostHog analytics.

2. Software Engineer · Novu (Remote)

   September 2022 - June 2025
   • Architected parts of Novu's core workflow orchestration engine. The system walks a trigger through a multi-step pipeline across email, inbox, SMS, and chat, with subscriber-preference evaluation at every layer.
   • Shipped the new Workflows API (NestJS, CQRS-style use-cases) replacing the legacy notification-templates system.
   • Built the step-condition system end-to-end on react-querybuilder + JSON schemas (UI + backend), enabling arbitrary per-step rules across workflows.
   • Designed the global subscriber preferences engine end-to-end (DAL → use-case → worker → headless and node SDKs).
   • Hardened auth (rate limiting, account lockout, password policy), added cursor pagination and fixed cache invalidation in the DAL, and built the Twilio-backed Novu SMS provider with Gupshup DLT compliance.
   • Created @novu/react and @novu/next from scratch. @novu/react overtook the legacy @novu/notification-center in npm weekly downloads within months of launch.
   • Led architecture and build pipeline on @novu/js, cutting bundle size 85% (157KB → 21KB) and load time 86% vs the legacy @novu/notification-center. Also architected @novu/client and rewrote it off axios onto native fetch.

3. Software Developer · Capital Numbers (Remote)

   March 2021 - August 2022
   • Owned most of the frontend for Blink Payment, a fintech payment-gateway platform. Built the payment flows (virtual terminals, repeat payments) and integrated card processors Cardstream and SagePay. Deployed via AWS CodePipeline, CodeBuild, and CloudFront.

4. Software Developer · NetTantra Technologies (now Hyscaler)

   January 2020 - January 2021
   • Sole frontend engineer on ZipDJ, a Spotify-style streaming platform built for DJs. Owned the frontend end to end, including the custom music player at the heart of the product, and integrated ElasticSearch for fast search with eager-loading performance work. Also integrated Mega.nz cloud storage for Spinvault.

Selected Work

• Hexbench

  A fast, private developer toolbox that runs entirely in your browser: format, decode, diff, hash, and test, with nothing you paste ever leaving the page. No install, works offline.

• @novu/react TypeScript · React · SolidJS

  React SDK for Novu, built from scratch as a modern, lightweight replacement for @novu/notification-center with faster load, an 85%-smaller bundle, and composable headless primitives. Overtook the legacy package in npm weekly downloads within months.

• EngineView Nuxt · Vue · TypeScript · Cloudflare Analytics Engine · SQL

  Multi-user, self-hosted dashboards and a SQL query runner for Cloudflare Analytics Engine: turn raw Analytics Engine data into shareable charts and ad-hoc queries without living in the Cloudflare dashboard.

• hour.zone Astro · React · TypeScript · Tailwind CSS

  Timezone comparison for remote teams. Pick two cities, get a 48-hour ledger with 9-to-5 overlap already highlighted. No clock walls, no mental math. Share the URL (hour.zone/bangalore/san-francisco) and everyone sees the same meeting slots. Keyboard-driven for ≤15-second use mid-Slack or mid-calendar invite. No signup.

• agent-skills Agent Skills · Bash · GitHub CLI · Claude Code

  A portable agent-skills marketplace: reviewloop (clear every PR reviewer), ciloop (drive failing CI to green), and standup (daily standup from your PRs), installable per-skill across Claude Code, GitHub Copilot CLI, Codex, and Cursor from one SKILL.md source.

Skills

Languages

TypeScript, JavaScript, Python, Go

Frontend

React, Next.js, Vue, Nuxt, SvelteKit, SolidJS, Tailwind CSS

Backend

Node.js, NestJS, Microservices, WebSockets, REST APIs, Zero-Trust Security

Data & Infra

MongoDB, PostgreSQL, Redis, Google Pub/Sub, AWS, Kubernetes

Education