Anurag Das, Developer in Kolkata, West Bengal, India
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Anurag Das

Bio

Anurag has 6+ years of industry experience in back-end programming for multinational companies and multiple startups. He has worked on a variety of mission-critical features, including solving complex problems on the supply side of the largest cab aggregator in India and optimizing legacy APIs for a multinational HR and insurance services firm. Anurag has a master's degree in mathematics and computer science and enjoys delivering innovative solutions.

Portfolio

IgniteTech
JavaScript, Next.js, React, Java, LangChain, Large Language Models (LLMs)...
Omaze
Go, PostgreSQL, AWS Lambda, Docker, TypeScript, Serverless, JavaScript...
Spotbuzz
Go, APIs, OpenAI, React Native, JavaScript, Amazon Web Services (AWS)...

Experience

  • Back-end - 6 years
  • Node.js - 6 years
  • MySQL - 6 years
  • Redis - 6 years
  • Back-end Architecture - 3 years
  • Go - 3 years
  • MongoDB - 2 years
  • Docker - 1 year

Preferred Environment

MacOS, Linux, Visual Studio Code (VS Code)

The most amazing...

...thing I've worked on is my first website (Aw3some.tv); it was similar to 9gag.tv, with 10,000 visitors per day at it's peak!

Work Experience

Senior AI Innovation Specialist | Software Engineer

2025 - PRESENT
IgniteTech
  • Led technical delivery for a Fortune 500 community platform serving millions of end users across enterprise deployments, owning architecture decisions and customization roadmaps for multiple concurrent client engagements.
  • Diagnosed and resolved a production SSO latency incident during a high-visibility client conference, isolating the bottleneck to auth token handling and shipping a fix that restored sub-second login times under peak load.
  • Scaled code review across distributed contributor teams by integrating CodeRabbit into the SDLC, reducing senior engineer review load while maintaining merge quality on a large legacy codebase.
  • Built RAG-based chatbot features on top of the community platform using LangChain and vector search, enabling semantic search and AI-assisted moderation across millions of user-generated posts.
  • Led a platform-wide, AI-enabled migration enabling clients to upgrade to the latest community platform version at no extra cost, unlocking modern features for enterprise tenants and delivering multi-million dollar value across the client base.
  • Delivered senior-engineer output at multiples of traditional velocity by pairing Claude Code and Cursor with disciplined AI-augmented workflows across architecture, refactoring, code review, and legacy migration work.
Technologies: JavaScript, Next.js, React, Java, LangChain, Large Language Models (LLMs), RAG Pipelines, Agentic AI, Generative Artificial Intelligence (GenAI), AI Integration, Claude Code, Security, User Roles, AI Tools, Claude, Cursor AI, API Architecture, Software Development, Distributed Software, Distributed Systems, LLM Integration, AI Agents, OAuth, Third-party APIs

Back-end Engineer

2025 - 2025
Omaze
  • Converted API endpoints in Go to equivalent Serverless endpoints in TypeScript, for high availability, and wrote extensive unit and integration tests to ensure predictable performance.
  • Fixed a caching mechanism affecting thousands of users during lottery draws.
  • Implemented bypass mechanisms for KYC to unblock internal teams while testing functionality.
  • Improved query performance by 23x, and brought down endpoint response time to a few milliseconds from over 5-6 seconds.
Technologies: Go, PostgreSQL, AWS Lambda, Docker, TypeScript, Serverless, JavaScript, Amazon EventBridge, Microservices, Generative Artificial Intelligence (GenAI), Security, AI Tools, API Architecture, API Gateways, Software Development, Distributed Software, Distributed Systems, LLM Integration, Third-party APIs

Lead Developer

2023 - 2025
Spotbuzz
  • Developed the entire back end from scratch using Go, creating numerous API endpoints to process user media and data and return AI-enhanced versions. Wrote code to handle payments, push notifications, and more.
  • Led the development of the cross-platform front end in React Native, implementing features such as login, back-end API integrations, Cloud Firestore, Firebase Authentication, RevenueCat, and Firebase Cloud Messaging.
  • Integrated LLMs (OpenAI, Anthropic) for image social media captions and hashtags generation.
  • Created a scalable Python back-end service to deploy open-source image and video generation pipelines using Stable Diffusion (1.5, XL), Flux, WAN, etc. Also deployed LORAs and ComfyUI workflows in production.
  • Developed the entire web app from scratch and integrated the back-end APIs as well. Also integrated payment gateways like PayPal and Razorpay for payments.
  • Managed a team of five developers across the front and back end, overseeing the development of various modules.
  • Created the entire marketing website from scratch. Integrated Strapi for blog posts as well.
Technologies: Go, APIs, OpenAI, React Native, JavaScript, Amazon Web Services (AWS), Amazon Simple Queue Service (SQS), Firebase, Google AdMob, RevenueCat, Cloud Firestore, Firebase Authentication, Back-end Development, API Development, Next.js, API Integration, Artificial Intelligence (AI), Vercel, Git, Front-end, Mobile Development, Android, iOS, React, Full-stack Development, Large Language Models (LLMs), OpenAI API, Amazon S3 (AWS S3), Responsive UI, ChatGPT, Mobile, Mobile Apps, Real-time Data, Software Design, Context API, React Query, Google Cloud Platform (GCP), Web Applications, Microservices Architecture, RESTFul APIs, Identity & Access Management (IAM), Scalable Application, CSS, HTML, Redux, Startups, Apollo, Minimum Viable Product (MVP), Python 3, Python, Microservices, Generative Artificial Intelligence (GenAI), Server Sent Events (SSE), Payments, Security, AI Tools, API Architecture, Software Development, Distributed Software, Distributed Systems, LLM Integration, OAuth, Dashboards, Third-party APIs

Tech Lead

2022 - 2023
Convosight
  • Integrated WhatsApp APIs to collect text and media data from end users and store it in Amazon S3 and DynamoDB. Made APIs to synchronize messages between both client apps and WhatsApp.
  • Developed API endpoints for an analytics dashboard that showed stats for Facebook groups, brand share of voice, sentiment analytics, and so on from a pre-populated DynamoDB table.
  • Managed a team of front-end and back-end developers to achieve the desired objectives.
Technologies: Go, Amazon DynamoDB, WhatsApp API, APIs, Webhooks, Back-end Development, API Development, API Integration, Git, Full-stack Development, Amazon S3 (AWS S3), Web Applications, Object-oriented Programming (OOP), Microservices Architecture, RESTFul APIs, Startups, Security, API Architecture, API Gateways, Software Development, Distributed Software, Distributed Systems, Dashboards, Third-party APIs

Software Development Engineer 2

2020 - 2022
Sequoia
  • Created a benefits portal and microsites that enable clients to view the benefits provided by their companies and the benefits they have enrolled in.
  • Implemented API endpoints in Python (Django) and Go (Fiber) that served more than 100k employees per day across prominent companies like Fitbit, Peloton, Dropbox, OpenAI, Netflix, Buzzfeed, and more.
  • Collaborated with the chief product officer and product managers to understand business requirements and develop innovative solutions.
  • Developed an architectural overview of many features, including the database design and API structure, and optimized legacy APIs and queries.
  • Managed a 3-member team. Assigned tasks and bug fixes, did peer reviews, and maintained code quality for the projects I worked on.
  • Created Confluence pages and documentation outlining detailed product flows, which made it easier to onboard new hires.
Technologies: Go, MySQL, Node.js, AWS Lambda, Python, APIs, REST APIs, JSON, REST, JSON REST APIs, API Design, API Documentation, Amazon Web Services (AWS), Express.js, SQL, Software Architecture, Technical Leadership, Leadership, Web Development, Back-end Development, API Development, Scrum, API Integration, Git, HIPAA Compliance, Amazon S3 (AWS S3), Software Design, FastAPI, Object-oriented Programming (OOP), Microservices Architecture, RESTFul APIs, Identity & Access Management (IAM), Scalable Application, GraphQL, Django, Microservices, Security, User Roles, API Architecture, Software Development, Distributed Software, Distributed Systems, Third-party APIs

Software Development Engineer

2019 - 2020
Ola
  • Developed flows for Driver and Vehicle Licensing Agency (DVLA) and self-assessment checks during Ola's London launch. We completed the self-assessment MVP quickly and reduced the onboarding turnaround time and load on support personnel.
  • Worked on a dynamic configuration system for ever-changing document configurations across different geographies.
  • Developed a car termination flow for situations where different drivers returned the same rental car, causing complexity. This feature reduced the turnaround time for rental car attachments from nine days to two days.
  • Collaborated with business heads and product managers to understand business requirements and develop appropriate solutions.
  • Coordinated and troubleshot edge cases and business requirement gaps with product support engineers, post feature deployments, and end-user feedback.
Technologies: Node.js, MongoDB, Redis, APIs, REST APIs, JSON, REST, JSON REST APIs, API Design, API Documentation, JavaScript, Express.js, Amazon Web Services (AWS), SQL, Back-end Development, API Development, Scrum, API Integration, Git, Amazon S3 (AWS S3), Real-time Data, Object-oriented Programming (OOP), Microservices Architecture, RESTFul APIs, Scalable Application, Security, API Architecture, Software Development, Distributed Software, Distributed Systems, OAuth, Third-party APIs

Full-stack Developer

2018 - 2018
Distill.io
  • Assisted in modifying the existing Chrome extension to add new features.
  • Created several back-end APIs that were consumed by the front end; also implemented social logins using Facebook and Google OAuth Libraries.
  • Developed a PostgreSQL extension for archiving old data and moving them to Amazon S3 to reduce database storage costs.
  • Migrated WebSocket connections from Node.js to Go and wrote code to support thousands of concurrent WebSocket connections.
  • Worked on trivial front-end features and enhancements using React and Backbone.js.
Technologies: Node.js, Go, Backbone.js, PostgreSQL, Chrome API, APIs, REST APIs, JSON, REST, JSON REST APIs, API Design, API Documentation, JavaScript, Amazon Web Services (AWS), Express.js, React, SQL, Full-stack, Stripe, Software Architecture, Front-end Development, UI Design, Web Development, Chrome Extensions, Back-end Development, API Development, API Integration, Git, Front-end, Full-stack Development, Real-time Data, Web Applications, RESTFul APIs, Bootstrap, CSS, HTML, Redux, Startups, Minimum Viable Product (MVP), Server Sent Events (SSE), Web Extensions, API Architecture, Software Development, Distributed Software, Distributed Systems, OAuth, Third-party APIs

Founder

2016 - 2017
Qlinkus Technologies
  • Created the back end from scratch, using Ruby on Rails and Node.js, and integrated payment gateways and the Google Maps API. Was instrumental in providing a smooth and fast checkout mechanism and proper retry mechanisms for payment failures.
  • Built the front-end user and vendor apps using Angular and Cordova. The mobile app was a hybrid app built on top of the responsive Angular web app.
  • Led and mentored a team of three junior developers (freshers), requiring extensive peer reviews.
  • Implemented administrative dashboards and APIs to provide overall order summaries and sales data.
  • Pitched our product team to vendors and onboarded them to our platform.
Technologies: Ruby on Rails (RoR), Node.js, MongoDB, MySQL, Google Maps API, APIs, REST APIs, JSON, REST, JSON REST APIs, API Design, API Documentation, JavaScript, Amazon Web Services (AWS), SQL, Full-stack, Mobile First, Software Architecture, UI Design, Mobile App Development, Web Development, Back-end Development, API Development, API Integration, Git, Front-end, Mobile Development, Full-stack Development, Amazon S3 (AWS S3), Responsive UI, Real-time Data, Google Cloud Platform (GCP), Web Applications, Microservices Architecture, RESTFul APIs, Identity & Access Management (IAM), Twilio API, CSS, HTML, Startups, Minimum Viable Product (MVP), Payments, Mobile Wallet, API Architecture, Software Development, OAuth, Dashboards, Third-party APIs

Intern

2015 - 2015
TinyOwl
  • Did courses on Ruby on Rails, Node.js, and Backbone.js and participated in hackathons, as a part of getting on-boarded.
  • Developed an email micro-service, which acted as a load balancer and used several mailing services under the hood, like Mailchimp, AWS SES, etc. Used to detect which of the third-party services were up and used them according to a preset priority.
  • Developed a write-up to give handover of my tasks to the tech team after my internship finished. Also gave a one-hour presentation regarding the same.
Technologies: Ruby on Rails (RoR), Node.js, Backbone.js, Amazon Simple Email Service (SES), Mailchimp, APIs, RabbitMQ, Back-end Development, API Development, Front-end, RESTFul APIs, CSS, HTML, Startups, Software Development, Third-party APIs

Experience

One-stop Food Ordering Solution

A one-stop food ordering app I built from scratch (back end and front end). I built the back end in RoR and Node.js; used MySQL to store transaction-related data; and MongoDB for invoices, order data, and more. I built the front end in Angular and integrated payment gateways, push notifications, and the Google Distance Matrix API.

Public Benefits Page

https://px.sequoia.com/sequoia
As a part of developing the Benefits micro-service, I developed a public-facing benefits API to be used by the front end so that future hires of our clients could see what medical benefits are available to them, even before joining us or getting enrolled in our system. Client Admins had an option to expose the public Benefits page using a feature flag on their side, and once enabled, we show benefits for default employee roles on the public website. The example URL attached is the public Benefits site for Sequoia itself.

OLA Cabs DVLA Integration

Worked on a back-end project to integrate DVLA. This ensured we had compliant drivers on our platform. We used to force drivers off the road if they committed more than a certain number of traffic violations. The check was performed at regular intervals using a cron job. I have attached a brief write-up by OLA on DVLA.

NumRush | Solve Time Bound Math Problems

A React Native-based math game app with over 1,500 levels consisting of time-bound problems. Users are scored based on correctness and the time it takes to solve the problem. On completion of a level, they are assigned a rating based on the score, which can be shared across various social networks. We also have an in-game leaderboard that ranks players based on their scores. After each level, the app shows how users are rated relative to other users.

SpotBuzz | AI Image Editor App

The development of SpotBuzz, an AI image editor app. During this project, I worked extensively on the back end and the front end, using Go, React Native, Firebase, Redis, and a few other technologies.

Markdown Editor

https://markdowneditoronline.com/
A Next.js- and Node.js-based markdown editor offering markdown previews, editing, and conversion from .md to HTML, DOCX, and PDF formats. Built in two days, the platform also allows users to create publicly shareable markdown URLs via markdowneditoronline.com.

Education

2011 - 2016

Integrated Bachelor's and Master's Degree in Mathematics and Computer Science

Indian Institute of Technology, Kharagpur (IIT Kharagpur) - Kharagpur, West Bengal, India

Skills

Libraries/APIs

Node.js, API Development, REST APIs, React, OpenAI API, Context API, React Query, Twilio API, Socket.IO, Backbone.js, Chrome API, Google Maps API, Stripe, WhatsApp API

Tools

Claude Code, Claude, Expo, Git, ChatGPT, Cron, Amazon Simple Email Service (SES), Mailchimp, RabbitMQ, Amazon Simple Queue Service (SQS), Firebase Authentication

Languages

Go, Python, JavaScript, SQL, CSS, HTML, TypeScript, Java, GraphQL, Python 3

Frameworks

Express.js, React Native, Next.js, Redux, Tailwind CSS, Bootstrap, Ruby on Rails (RoR), Django

Paradigms

Microservices, REST, Mobile Development, API Architecture, Back-end Architecture, UI Design, Object-oriented Programming (OOP), Microservices Architecture, Scalable Application, Scrum, Mobile App Design, HIPAA Compliance

Platforms

Docker, Android, iOS, Mobile, MacOS, Linux, Visual Studio Code (VS Code), Amazon Web Services (AWS), Vercel, Google Cloud Platform (GCP), AWS Lambda, Zendesk, Firebase, RevenueCat

Storage

MySQL, PostgreSQL, JSON, MongoDB, Redis, Amazon S3 (AWS S3), Amazon DynamoDB, Cloud Firestore

Industry Expertise

E-learning

Other

Back-end, APIs, JSON REST APIs, Full-stack, Software Architecture, Technical Leadership, Leadership, Architecture, Web Development, API Integration, Front-end, Full-stack Development, Responsive UI, Mobile Apps, Web Applications, RESTFul APIs, Startups, AI Integration, User Roles, AI Tools, Cursor AI, Software Development, Distributed Software, Distributed Systems, LLM Integration, OAuth, Third-party APIs, Back-end Development, API Design, API Documentation, Mobile First, Mobile App Development, Front-end Development, OpenAI, OpenAI GPT-3 API, CI/CD Pipelines, GitHub Actions, Chrome Extensions, Artificial Intelligence (AI), Education Technology (Edtech), Large Language Models (LLMs), Real-time Data, FastAPI, Identity & Access Management (IAM), Minimum Viable Product (MVP), Generative Artificial Intelligence (GenAI), Server Sent Events (SSE), Payments, Security, QR Codes, Web Extensions, Mobile Wallet, API Gateways, Dashboards, Algorithms, Discrete Mathematics, Probability Theory, ChatGPT API, Webhooks, Google AdMob, Software Design, Apollo, Serverless, Amazon EventBridge, LangChain, RAG Pipelines, Agentic AI, Vibe Coding, AI Agents

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