i3w

Backend Engineer

Consumer · Companion
Hiring manager: Manas Singh

About the Role

i3w is a 7-person AI-native team that has shipped three consumer products and a B2G platform. InfiNotes — our study notes product — hit 9,800+ registered users and 615 paying customers within weeks of launch. Companion, our voice AI tutor, is launching April 2026. The backend that powers all of this is growing and Manas Singh, who owns it, needs a peer.

You will primarily own the InfiNotes backend: the API layer, content delivery, payments (Razorpay), user management, and analytics pipelines. You will also pick up Companion backend work alongside Manas — session management, real-time infrastructure, and integrations with the AI/ML layer. Bharat Agarwal oversees the technical architecture and you will collaborate with him regularly on design decisions.

This is not a role for someone who wants to move tickets. You will own services. You will make calls under pressure. The codebase is young and there is room to shape it right. We want someone with speed and fundamentals — not one or the other.

What You'll Do

  • Own and extend the InfiNotes backend: REST APIs, content delivery, Razorpay payment webhooks, user sessions, and subscription state
  • Build and maintain Cloud Run services in Node.js, deployed on GCP
  • Design and optimize PostgreSQL schemas — you write queries that perform, not queries that work
  • Support Companion backend alongside Manas: WebSocket session handling, real-time state, AI service integration
  • Build internal tooling for content management, analytics, and operations
  • Collaborate with Bharat on service boundaries, data contracts, and architectural decisions
  • Set up monitoring and alerting for production services — you own what you ship
  • Pick up new internal projects as they come — we have at least three InfinityLearn internal tools in the pipeline, and the probability of more is high

What We're Looking For

  • 2+ years of professional backend experience with Node.js in production
  • Strong fundamentals: HTTP, auth patterns, async patterns, error handling — you understand what's happening under the hood
  • Experience with PostgreSQL: schema design, query optimization, indexing, transactions
  • Comfort with GCP or a comparable cloud platform (Cloud Run, Cloud SQL, Pub/Sub)
  • Experience with payment gateway integrations (Razorpay, Stripe, or similar)
  • High execution speed — you ship, you iterate, you do not disappear into research
  • Ability to collaborate closely with one other backend engineer without stepping on each other

Nice to Have

  • Experience with WebSockets or WebRTC for real-time backend services
  • Familiarity with Firebase (Auth, Firestore) as a complement to a primary SQL backend
  • Experience integrating with LLM APIs (Gemini, Claude, OpenAI) from a backend service
  • Comfort with Indian payment flows: UPI, Razorpay subscriptions, GST compliance
  • Experience on a small team — you are used to wearing multiple hats and not waiting for tickets
  • Comfort using AI coding tools (Claude Code, Copilot, Cursor) as part of daily workflow

Apply: bharat@i3w.ai