Currently building at Cognavi

Amit Rai

Full Stack Engineer

Full-stack engineer, frontend-heavy — 5+ years building scalable, high-performance web & mobile apps end to end. I currently lead frontend at Cognavi, delivering large-scale web platforms used by 400,000+ users, and I'm just as at home in the Node/MongoDB/Redis services, real-time systems, and deployments underneath as I am in the React architecture on top.

Pune, India
0+ yrs
Experience
0K+
Users served
Lead
Frontend teams
View my workFind me online
Amit Rai

About

What I do

I'm a full-stack engineer who leans heavily frontend — 5+ years building scalable, high-performance web and mobile apps. At Cognavi I lead frontend for large-scale, data-heavy platforms serving 400,000+ users — owning the architecture, mentoring teams of 3–4, and setting the standards we ship by.

I'm at my best in the hard parts: complex data-driven UIs, custom table and search systems over large datasets, real-time apps over WebSockets, and canvas rendering with PDF export — plus the Node/MongoDB/Redis services, media pipelines, and deployments that back them. I also write tutorials on Medium about the things I figure out along the way.

I'm comfortable owning infrastructure end to end, too — I've run workloads across AWS, GCP, DigitalOcean droplets, and bare-metal CherryServers for blockchain, and I deploy backends on Railway. (I've even talked AWS into waiving a hefty surprise bill.)

// since the pre-AI era
I've been shipping code since back when Stack Overflow was the lifeline — long before AI could write it for you. I learned by reading source, debugging by hand, and understanding the stack top to bottom. AI is a great accelerator today, but the fundamentals were earned the long way — and it shows in how I architect, debug, and reason about systems.

Frontend

ReactNext.jsReact NativeTypeScriptJavaScript (ES6+)HTML5 / CSS3SSR / SSGAccessibility (WCAG)Performance

UI & Styling

Tailwind CSSMaterial UIAnt DesignBootstrapStyled ComponentsD3.js

State, Data & Realtime

ReduxReact QueryZustandREST APIsWebSockets

Backend

Node.jsExpressMongoDBRedisFirebaseFFmpeg / MPEG-DASH

Cloud & Hosting

AWSGCPDigitalOceanCherryServersRailwayNginxLinux

Testing & Build

CypressJestReact Testing LibraryViteWebpackGitHub Actions

Practices

Code & PR ReviewsDesign SystemsStorybookBit.devFigmaAgile / Scrum

Career

Experience

Frontend Engineer (Lead)

Cognavi India Pvt. Ltd.

Mar 2023 – Present

Lead frontend for large-scale, data-heavy web platforms serving 400,000+ users.

  • Lead multiple teams of 3–4 engineers — owning frontend architecture, code & PR reviews, and engineering standards.
  • Architected data-heavy platforms with complex multi-step workflows and role-based access, scaling to 400,000+ users.
  • Built a custom TanStack Table system with server-side pagination, selection state, and optimized rendering.
  • Added fast search and filtering over large datasets with MeiliSearch; tuned performance with React Query caching and memoization.
  • Shipped AI-assisted features with editable, human-in-the-loop output.
  • Implemented SSO authentication with white-label theming, and diagnosed & fixed performance and production issues across the frontend.
ReactTypeScriptTailwind CSSMaterial UIReact QueryCypress

Frontend Developer

Eoraa & Co.

Sep 2020 – Feb 2023

Built enterprise dashboards and customer-facing web apps for Japanese clients under strict, pixel-perfect quality standards.

  • Delivered complex operational dashboards, admin panels, and internal management tools across multiple enterprise products.
  • Built multilingual (i18n) interfaces and maintained a modular, reusable component architecture with Bit.dev and Storybook.
  • Contributed to shared design-system patterns that kept UI consistent and development fast across products.
ReactTypeScriptBootstrapStorybookBit.dev

Work

Featured projects

Resume Builder

2026

Canvas-based resume editor with PDF export & ATS scoring.

A canvas-based resume builder with drag-and-drop editing, live preview, and dynamic pagination — including page-break handling with orphan/widow control and print optimization. Exports pixel-consistent PDFs that match the editor, and runs an ATS scoring workflow to help tune resumes for applicant-tracking systems.

TypeScriptReactCanvasPDF ExportATS
Source

Solana Token Analyzer

2025

Browser extension for real-time Solana token insights on DexScreener.

A browser extension that let traders track and analyze Solana tokens directly inside DexScreener — surfacing real-time liquidity, wallet activity, and transaction data inline, without leaving the page. Backed by a Node service that pulled and analyzed on-chain Raydium pool and transaction data.

Browser ExtensionSolanaWeb3TypeScriptNode.js

Delisted — on-chain data costs got too high to keep it running

Adaptive Video Streaming

2023

Chunked upload + MPEG-DASH adaptive playback, end to end.

An end-to-end video platform. The React client uploads large files in fault-tolerant chunks with Resumable.js; the Node/Express backend transcodes them with FFmpeg into multiple bitrates (240p / 520p / 720p), generates MPEG-DASH manifests with MP4Box, and serves bandwidth-aware adaptive playback through Nginx on AWS EC2.

ReactNode.jsFFmpegMPEG-DASHAWS
ClientServerArticle: Part 1Article: Part 2

D3 Calendar Heatmap

2023

Hourly, weekly & monthly activity heatmaps with D3.js.

A configurable calendar heatmap built with D3.js and Next.js that renders hourly, weekly, and monthly views for arbitrary time ranges. Uses date-fns for date math and Tailwind for styling — handy for visualizing activity density and spotting patterns at a glance.

D3.jsTypeScriptNext.jsdate-fns
SourceArticle

Firebase + Twilio Auth

2022

Google sign-in & phone OTP verification for React Native.

A React Native (Android) authentication flow that combines Firebase Google Sign-In with Twilio-powered phone-number OTP verification, backed by a Node/Express server — covering the full handshake from social login to a verified phone number.

React NativeFirebaseTwilioNode.js
SourceArticle

More projects

renderly.cc

Next.js + Tailwind marketing site, live in production.

Next.jsTailwind CSSReact
SourceLive

Image Processor

Browser image-processing client with a Node backend.

ReactNode.jsImage Processing
ClientServerLive

GeneralElevator

React Native client & admin mobile apps.

React NativeMobile
ClientAdmin

Real-time Trading System

Market data, strategy execution & order management — entirely in Node, no Python/pandas.

Node.jsWebSocketsRedisTypeScript

Real-time Chat

WebSocket chat with an Ant Design React frontend.

WebSocketsNode.jsReactAnt Design

Writing

Articles & tutorials

Personal↳ D3 Calendar Heatmap

Calendar Heat Maps with D3.js & Next.js

Building monthly, weekly, and per-day hourly heatmaps for arbitrary time ranges with D3.js, date-fns, and React/TypeScript.

eoraa.co↳ Firebase + Twilio Auth

Firebase Google Sign-In + Twilio OTP in React Native

A step-by-step Android guide to combining Firebase Google login with Twilio phone-number verification.

eoraa.co↳ Adaptive Video Streaming

Chunked Video Upload + Adaptive Streaming (Part 1)

Uploading large videos as fault-tolerant chunks with Resumable.js and a React client, with automatic retries.

eoraa.co↳ Adaptive Video Streaming

Adaptive Video Streaming Backend (Part 2)

Handling uploaded chunks and transcoding to MPEG-DASH with FFmpeg & MP4Box on AWS EC2 + Nginx for bandwidth-aware playback.

Read more on Medium

Snippets

Code snippets

TypeScript

Order Flow Chart

A custom order-flow chart built on the Lightweight Charts (TradingView) primitives API — filling the gap since the library ships no built-in order-flow series, alongside candlesticks in React/TypeScript.

JavaScript

Twilio OTP Server

Minimal Twilio server for sending & verifying one-time passcodes.

JavaScript

FFmpeg DASH Args

FFmpeg argument builder for generating MPEG-DASH (MPD) renditions.

Node.js

Resumable Upload Server

Server-side handler for Resumable.js fault-tolerant chunked uploads.

JavaScript

Google Sign-Up Button

A reusable Google sign-up button component.

JavaScript

Formik Form

An example form built with Formik.

All gists on GitHub

Contact

Find me online

This is my corner of the web — where I write, build, and share what I'm working on. Here's where else you'll find me.

LinkedInEmail me