Creative engineering portfolio of Harjot Singh: hands-on Tech Lead with six years of experience shipping distributed systems, B2B commerce platforms, RAG-backed AI search and ranking engines, conversational AI, server-driven UI and AI-leveraged developer workflows. Available for senior engineering, tech-lead and consulting engagements — remote-first from Delhi (GMT+5:30). Stack: Node.js, Bun, Fastify, NestJS, Spring Boot, PostgreSQL, Kafka, Redis, Next.js, React, TypeScript, AWS, Lambda, Kubernetes, RAG and agentic LLM tooling.
01 — AboutHS
Tech lead · six years
I lead engineering teams and ship the unglamorous parts — the migrations, the queues, the P95s — so the product feels calm.
- years shipping
- commerce handled
- platform P95
Currently
I’m a backend-led tech lead with six years across B2B commerce, health-tech, logistics and SaaS. Right now that means the AI layer of a diamond marketplace: RAG-backed AI search, a ranking engine and a support chat, shipped on the same backend that moves the inventory.
Most of the work is the part nobody photographs: migrations that ship, queues that don’t drop, P95s that come down and stay down, retrieval that returns the right stone. Backend first. Product always.
How I work
- 01Think in systemsModel the failure paths first. Make the happy path boring.
- 02Stay close to productArchitecture matters when it changes what a customer can do.
- 03Leave a clear trailUseful logs, explicit decisions, migrations teams can trust.
02 — Selected work04
Hover to preview · click to play the demo
- 01Diamond B2B platform2025
Live inventory, instant ordering, RAG-backed AI search and a ranking engine for a high-value diamond marketplace handling more than $100M in inventory and sales.
- 02Server-driven site builder2024simple.drop footer
A block-schema website builder that lets non-engineering teams compose and publish more than 100 sites without a deployment.
- 03Multi-tenant AI support2025
A role-aware support platform with tenant-specific knowledge, scripted personas and escalation rules, delivered in six weeks.
- 04AI search & ranking2025
Natural-language search over a live diamond inventory: query understanding, hybrid lexical and semantic retrieval, a business-aware ranking engine and grounded answers that cite the stones they recommend.
04 — Capabilities05
What I actually do
- 01Backend systemsservices, APIs, migrationsnodebunfastifynestjsspring05
- 02Data & messagingmodelling, streams, cachingpostgreskafkaredis03
- 03AI engineeringRAG, AI search, ranking, eval loopsopenaipineconeragranking04
- 04Product surfacesweb and mobile clientstypescriptnext.jsreactflutter04
- 05Cloud & deliveryship it, then keep it upawslambdakubernetesdocker04
05 — Contact
Open for new work
Let’s buildthat holds.
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