Open to staff-level rolesFull-stack / AI systems · Selective freelance

Rupam Das · Bengaluru

Full Stack AI Engineer

I design and own production agentic systems — multi-tenant platforms, tool-calling agents, and the isolation, evals, and delivery pipelines that keep them safe in production.

Explore Systems Work

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93%latency reduction3s → 200ms
10K+LLM requests / dayproduction pipelines
95%test coveragezero-downtime releases
5,000concurrent users40% faster loads

Selected systems work

Production constraints I owned

Tenancy, tool-calling evals, scale, and real-time safety — with the architecture and the numbers.

PostQodeJul 2025 – Present

Multi-tenant AI agent marketplace

Architected two-layer multi-tenancy for a 100-model, 61-route backend so purchased AI agents cannot cross tenant data — then deployed those agents into buyers’ own Azure subscriptions.

PrismaSQL Server RLSAzure Front DoorAPIM+6 more

35tenant-scoped models

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PostQodeJul 2025 – Present

Eva — agentic shopping assistant

Built an SSE-streaming, tool-calling agent on the Azure OpenAI Responses API with 21 RBAC-gated tool groups (~15 write tools), retry/circuit-breaker resilience, PII scrubbing, KB-grounded citations, and a 2,000+ line golden-eval suite in CI.

Azure OpenAI Responses APISSERBAC tool groupsCircuit breakers+3 more

2,000+golden-eval lines in CI

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How I Build

What I own in production

The engineering lenses I apply on every system — isolation, agents, latency, and the release path.

Multi-Tenant & Isolation

Hard data boundaries, sandboxed execution, and zero-trust tenancy.

Containerized environments, tenant data boundaries, egress security, and strict quota enforcement across multi-tenant clusters.

Agentic & Tool Calling

Autonomous reasoning, deterministic execution, and schema verification.

Multi-step tool invocation, streaming function calling, recursive decomposition, and structured output guarantees.

Latency & Streaming

Sub-second token delivery and bidirectional realtime audio.

WebRTC duplex streaming, SSE pipelines, edge caching, and optimized token throughput for conversational intelligence.

Production & Evals

Deterministic testing, observability, and automated CI guardrails.

Automated regression suites, LLM-as-a-judge benchmarking, tracing telemetry, and zero-downtime deployment pipelines.

Open Source

Public artifacts

Self-hosted RAG, a 19-tool Chrome extension, and production-shaped starter kits — live links, not decks.

devtools-engine.ts

Manifest V3

export const devtools = {

tools: ["DOM Outliner", "Z-Index 3D", "A11y Audit"],

manifest: "v3",

render: () => panel.mount(document.body),

};

// 19 visual debugging tools mounted

2024

Frontend Dev Helper — Browser Extension DevTools Suite

Manifest V3 extension that replaces 8+ legacy tools with 19 visual debuggers — DOM outliner, z-index 3D, contrast, a11y audit, and network analyzer.

TypeScript
React 18
Chrome MV3
Firefox MV2
Vite
CRXJS
+8 more

View Case StudyOpen Source

devtools-engine.ts

Manifest V3

export const devtools = {

tools: ["DOM Outliner", "Z-Index 3D", "A11y Audit"],

manifest: "v3",

render: () => panel.mount(document.body),

};

// 19 visual debugging tools mounted

2024

RAG Starter Kit — Production-Grade AI Document Chat Platform

Production-shaped, self-hosted RAG chatbot boilerplate: streaming chat, voice I/O, multi-user rooms, S3, Playwright E2E, one-click Vercel deploy.

Next.js 15
React 19
TypeScript
PostgreSQL
pgvector
Prisma
+18 more

View Case StudyOpen Source

View all projects

Explore the RAG starter kit, FrontendDevHelper, and the rest of the public work.

All projects

Career

Roles, owned end-to-end

Three production seats — isolation, agents, and real-time systems — not a list of duties.

01PostQode· Bengaluru, India

Jul 2025

Software Engineer

Two-layer tenancy on 35 of 100 models, Eva with 21 RBAC-gated tool groups and golden evals in CI, and zero-trust Azure deploys into buyer subscriptions.

NestJSNext.jsAzure ARMSocket.IONode.js

02EL Nova Labs· Remote

Mar 2024

Software Engineer

Led 5 engineers on a React/Redux/GraphQL ERP for 5,000+ concurrent users; 40% load-time cut; RAG over 10,000+ docs at 85% retrieval accuracy; 95% coverage and zero-downtime releases.

ReactRedux ToolkitGraphQLNode.jsTypeScript

03Big Wings LLC· Chandigarh, India

Jan 2023

Frontend Engineer

Sole frontend owner for fleet tracking of 200+ vehicles; Samsara ELD + WebSockets; emergency response 20 → 10 minutes.

ReactTypeScriptReduxWebSocketsSamsara ELD API

Explore career timeline & verified achievements

Toolkit

Shaped by production constraints

Tenant isolation, agent evals, and zero-downtime delivery — not a course list.

01 // AI

Agentic AI

Autonomous agents, voice pipelines & golden evals

Azure OpenAI (Realtime)

PROD

LangChain & LangGraph

PROD

Self-hosted RAG (pgvector)

PROD

Tool-calling Agents (RBAC)

PROD

Golden Evals in CI

PROD

Vapi Voice Pipelines

PROD

< 200ms latency · 2k evals

02 // PLATFORM

Isolation & Platforms

Multi-tenant RLS, zero-trust & cloud architecture

Multi-tenant SaaS

PROD

Prisma + SQL Server RLS

PROD

Zero-trust Networking

PROD

Azure Front Door & APIM

PROD

ARM Orchestrator

PROD

Session Context Guards

PROD

Zero tenant bleed · RLS

03 // STACK

Full Stack Systems

React 19, high-throughput APIs & real-time streams

TypeScript & React 19

PROD

Next.js 16 App Router

PROD

ElysiaJS & Node.js

PROD

WebSockets & SSE Streams

PROD

PostgreSQL & Redis

PROD

Tailwind CSS 4

PROD

React 19 · Elysia · SSE

04 // CI/CD

Release & Delivery

Zero-downtime deploys, automated CI & supply chain

Vitest & Playwright E2E

PROD

GitHub Actions CI/CD

PROD

Zero-downtime Blue-Green

PROD

Docker & Containers

PROD

Trivy, SBOM & Notation

PROD

Turbopack & Webpack

PROD

SLSA Provenance · SBOM

Explore complete technical proficiency matrix

Developer Utilities

Developer Tools Sandbox

6 of 60+ free developer utilities. Fast, offline-first, and zero dependencies.

100% Client-Side · Your Data Never Leaves Your Browser

JSON Formatter

Validate, format, and minify complex JSON structures.

Try it

JWT Decoder & Debugger

Decode JSON Web Tokens offline to view headers, payloads, and signatures.

Try it

Password Generator & Checker

Generate highly secure passwords and check their entropy.

Try it

Timestamp Converter

Unix timestamp to Human date conversion made simple.

Try it

Color Converter

HEX, RGB, HSL, OKLCH color converter.

Try it

API Tester

Simple HTTP client for testing APIs.

Try it

View All Tools

Open for Staff-Level Roles & High-Impact Advisory

Let’s talk about the system you need to ship

Hiring managers: I am open to staff-level full-stack and AI systems roles. Founders: I take a small number of engagements where I own architecture through production — agents, tenancy, and the pipeline.

Schedule Architecture Review rupam@rejisterjack.com

Average response: < 24h·Bengaluru (IST) / Remote Worldwide·Zero-obligation confidential review