Building backend systems

that power millions.

Contribution_Architecture.sys

v2.0.26

From one tenant to a fleet of them

System Design

Data Architecture

Backend.

Excellence.

Building systems that hold up in production, for real users, on a real budget.

About

Twelve clients. One codebase. Mine to keep running.

I'm a backend and platform engineer. Right now that means owning a multi-tenant loyalty platform in production — one codebase serving twelve white-labelled clients, and everything underneath it: the Postgres schema, the tenancy rules, the CI that ships it, and the pager when it doesn't.

Most of what I actually know came from running things that were already live. Idempotent rollouts, blast-radius reasoning, row-level isolation — those aren't ideas I read about. They're the shape of problems I've had to fix at an inconvenient hour, with real users on the other side.

I write too — a book, and whatever else is bothering me that week.

Backend ArchitectureScalable systems

700+ DSAProblems solved

Hackathon WinnerMultiple wins

Speaker & WriterTech community

NestJS

TypeScript

PostgreSQL

React Native

React

Redis

BullMQ

Docker

GitHub Actions

Nginx

Multi-tenant SaaS

Java

Spring Boot

Kafka

QDrant

Spring Security

NestJS

TypeScript

PostgreSQL

React Native

React

Redis

BullMQ

Docker

GitHub Actions

Nginx

Multi-tenant SaaS

Java

Spring Boot

Kafka

QDrant

Spring Security

Experience

Where I've shipped.

Abacus

Current

Backend Engineer — Multi-tenant Loyalty SaaS/May 2026 — Present/Full-time

I run a multi-tenant loyalty platform in production — one codebase serving 12 white-labelled B2B clients across a NestJS backend, React admin, and React Native mobile app. Owner of the platform end-to-end: schema, business logic, CI/CD, production deploys, and on-call.

What I do

Ship features across backend, web, and mobile from a single codebase — with per-tenant customization baked in at build time (config-driven, not runtime-forked).
Onboard new tenants zero-to-Play-Store end-to-end: database seeding, per-tenant branding, mobile CI, backend cutover, portal smoke tests. Encoded the whole process as an idempotent script plus acceptance suite so bug classes I hit once can't recur.
Own production deploys — self-managed VPS, Docker Compose per stack, nginx edge routing, TLS, database migrations, incident response.
Build security-critical flows end-to-end: authentication, KYC pipelines (manual review and digital verification against government APIs), payment payout integrations with HMAC-signed clients, async poll workers, and refund ledgers.
Enforce tenancy invariants across the codebase: row-level org scoping, append-only money ledgers, and subdomain-scoped credential routing so tenants can't leak into each other's data.
Manage a fleet of tenant release branches — cross-branch propagation, cherry-pick audits, staged rollouts, per-tenant APK builds.
Automate the boring parts of my own job: acceptance test suites, CI/CD workflows, release scripts, over-the-air JS update delivery for post-launch fixes.

Systems I own in production

Multi-tenant NestJS backendPooled Postgres, row-level tenancy, BullMQ workers, Redis cache
Tenant admin web consoleRole-based access, tenant-isolated content
React Native mobile appPer-tenant branding, deep-linking, force-update gating, OTA JS updates
Payment payout pipelineAsync retry, reconciliation, subdomain-scoped credentials
Automated tenant onboardingIdempotent orchestrator plus acceptance suite covering every recurring failure mode
Cross-branch propagation auditSignals which fixes have landed where across the 10+ branch fleet
Self-hosted OTA deliveryShips JS-only fixes fleet-wide in minutes, no APK rebuild cycle

What running this has taught me

Multi-tenant architecture in the real world: when to pool, when to isolate, and how to move between the two without a migration outage.
Ownership discipline: writing durable runbooks and acceptance tests so knowledge outlives any single session or engineer.
Production risk management: idempotency, rollback paths, blast-radius reasoning, atomic-transaction hygiene, and why “it compiled” is the beginning of testing rather than the end.
Cross-stack debugging: the same root cause wears different masks on backend, web, and mobile — the fix belongs at the right layer, not the closest one.
Solo-operator throughput: knowing when to automate, when to grind, and when the right move is to write the tool instead of doing the work.

NestJSTypeScriptPostgreSQLTypeORMRedisBullMQReactReact NativeDockerGitHub ActionsNginxMulti-tenant SaaSCI/CD

Noble Kode

Full Stack Intern/Aug — Nov 2025/On-site, Delhi

Shipped customer-facing commerce features onto live client storefronts.

Built a guest cart and OTP-based authentication flow, enabling guest-to-user conversion across live client stores.
Designed a Cloudinary image conversion pipeline processing 2,000+ images, cutting media delivery latency by 45%.
Added automated transactional email and responsive B2B lead-generation tools.
Moved hardcoded credentials into environment variables and tightened secret handling.

Node.jsCloudinaryNodemailerJavaScript

Cyberent Cube

Java Full Stack Intern/Mar — Jul 2024/Remote

First real team environment — half engineering, half getting five other people unblocked.

Led a team of 6 interns across client website builds, running hands-on Git and GitHub training; project turnaround dropped 25%.
Overhauled the backend of MetaDefender, an internal malicious-file detection tool, improving detection accuracy by 30% within the first quarter.

JavaSpring BootGit

Selected Work

Projects that define impact.

StreamLite

Research-backed hybrid Live + VOD streaming backend built to hold up under high-concurrency workloads on deliberately resource-constrained infrastructure.

Event-driven architecture separating control and data planes for fault isolation

Spring BootKafkaRedisFFmpegSpring Security

Aries

gRPC-based distributed rate limiter delivered as a service, implementing the standard algorithm family behind one interface.

Rate-limiting as infrastructure rather than per-service boilerplate

JavagRPCDistributed Systems

Doclite

CLI tool that generates ready-made documentation scaffolding across five-plus project styles, so a new repo starts documented instead of promising to be.

Turns the doc-writing step from a chore into a flag

Node.jsJavaScriptCLI

Avasyu

Cloud-based CRM with contact management and email integration, secured with OAuth via Spring Security.

End-to-end CRM built solo, from schema to auth to UI

Spring BootThymeleafPostgreSQLSpring Security

Achievements

Milestones that matter.

Technical Wins

Hackathons & competitions

0st

National Finalist

Hackathon achievement

DSA Problems

Solved on LeetCode

IIT Delhi Finalist

Prestigious recognition

Microsoft Student Ambassador

Recognized for technical leadership and community impact

Speaker & Writer

Sharing knowledge through talks and technical articles

Open Source Contributor

Contributing to projects that matter

Recognition

Awards & Honors

2024

BITS Pilani 4 Day Hackathon

First place in the BITS Pilani 4 Day Hackathon, building an application system for blood donation services that processed real-time data from 10,000+ concurrent connections.

HoverTap to view certificate

2024

HackIndia State Level Hackathon

Awarded for innovative problem identification and technical solution development inside the WEB3 category among 250+ participants across India. Got 2nd in Haryana

HoverTap to view certificate

2024

Youth Speaker Series

Became one of the youngest speakers to speak at the Youth Speaker Series, sharing insights on environment and innovation. Came in top 8 in University level competition

HoverTap to view certificate

2025

Tech Spark Hackathon

Awarded First in the 2 day hackathon for building a sustainable solution on blockchain payment that can be provided to charity.

HoverTap to view certificate

Education

Still a student. Already on call.

2022 — 2026Final year

J.C. Bose University of Science and Technology, YMCA

Bachelor of Technology — Computer Science & Engineering

Artificial Intelligence & Machine Learning

CGPA: 8.6

2019 — 2021

St. John's School

Senior Secondary & Secondary

Class 12: 96%
Class 10: 90%

How I work

Four rules I actually follow.

Back it up before you break it.

Every deploy starts by copying whatever I'm about to overwrite, and saying so out loud before I touch anything. Thirty seconds of paranoia has rescued more evenings than any test suite I've written.

Deleting is shipping.

The largest thing I shipped this year was four hundred thousand lines going away — two dead subsystems, fifty-five unused tables. Server load fell from 10.27 to 0.19. Nothing I could have added would have done that.

Evidence, then claim.

"It works" is a claim. A command and its output is evidence. I've learned not to say the first without pasting the second, because the gap between them is where the embarrassing bugs live.

Stop when you're unsure.

When something that worked an hour ago is suddenly broken, two sentences and a pause beat twenty minutes of confident thrashing. Most bad outages I've watched were someone who didn't want to look slow.

The one word

Relentless.

Get inspired to learn. Then learn to inspire.

— Lakshya Bhardwaj/Mine.

The fastest way to attract what you want in life is to deserve it — by doing so much work that it becomes unreasonable not to achieve it. Do so much work that it becomes unreasonable that you fail. The seat at the table is yours if you want it. Do the hard work. Build the skills no one can ignore. Adjust the mindset to where you want to go, then pull up a chair and sit down. Do so much work with relentless obsession that when people see you, they are grateful they don't have to compete against you. The fastest shortcut is to stop looking for shortcuts. Do the work.

— Alex Hormozi/Not mine. Still runs my week.

Life & Moments

See My Life's Journey

Also an author

I wrote a book.

Fcuk Around and Find Out

Own Your Consequences Or Get Owned by Them

The questions of “what-ifs” take a part of your present.

Taking risks can be daunting, unpredictable, and at times, downright uncomfortable. But it’s also essential for growth, learning, and discovering what we’re truly capable of.

This book is a raw, unfiltered exploration of the consequences that come with stepping outside your comfort zone and embracing the unknown.

It’s for those who are tired of playing it safe and are ready to face life’s challenges head-on. If you’re willing to bet on yourself, break the boundaries, and accept the repercussions, then it’s time to…

fcuk around and find out.

Read it on Amazon

Publisher /: OrangeBooks Publication
ISBN /: 978-93-6554-497-8
Format /: Non-fiction · Paperback & eBook

Writings

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Contact

Let's build something meaningful.

Have an idea or project in mind? I'd love to hear about it. Let's create something extraordinary together.

Email GitHub LinkedIn LeetCode Codolio

Lakshya Bhardwaj — Backend & Platform Engineer