manojOS · boot sequence
0%
welcome to manoj's desk _
draw mode · press ESC to stop
🐛 catch the bugs!
⏱ 20s 🐛 caught: 0 missed: 0
quack 🦆
~ ~ ~
DEPLOY
FRIDAY
NIGHTS.
(kidding. please don't.)
,MK '26
hey recruiter 👋
scroll? no. click
the laptop.
TODO:
▢ write tests
☑ break things
☑ fix things
remember: every
webhook wants to
retry. let it.
HOURS UNTIL
THE WEEKEND
·
♪ ♫ ♪
DDIA
ch. 8: the trouble with distributed systems
...clocks lie. networks lie. so does your monitoring...
9:41
slack
kafka is fine
$ hello, friend ▊
click to enter

✨ secret drawer

🐛 play bug-hunt
🎉 throw confetti
🎨 party mode
🔄 reset the desk
📝 leave a note

Manoj's Desk

👆 click the laptop for the "real" portfolio
crafted by manoj
manoj kumar
designed and engineered by hand · 2026
brewed on too much coffee · powered by curiosity
manojka.swe@gmail.com
linkedin · github
coffees347
uptime99.9%
secrets0/38
resume.pdf
MANOJ KUMAR
+1 (682) 360-0111 | manojka.swe@gmail.com | LinkedIn | Portfolio

Summary

Software Engineer with 5+ years of experience building scalable full-stack applications using Java, Spring Boot, React, TypeScript, Kafka, and AWS. Strong experience developing REST APIs, event-driven systems, and high-performance applications using PostgreSQL, Redis, Docker, and Kubernetes. Skilled in improving application performance, reliability, and CI/CD pipelines, with additional experience building LLM-assisted solutions and Python-based forecasting pipelines. Proven track record of delivering production systems across transaction, payment, booking, and content platforms.

Skills

  • Languages & Frameworks: Java, Spring Boot, Spring Batch, Spring MVC, Angular, React.js, TypeScript, JavaScript (ES6+), Python, Node.js, Redux, GraphQL, Next.js, Express.js, FastAPI, Hibernate
  • Frontend & Visualization: React.js (Hooks, Redux, Context API), Next.js, Angular, Tailwind CSS, Material UI, Storybook, SSR/SSG, dynamic imports, code splitting, WCAG 2.1, ARIA, responsive design, PWA, A/B testing, accessibility
  • Cloud & DevOps: AWS (EC2, S3, Lambda, EKS, CloudFront, CloudWatch), Docker, Kubernetes, Terraform, Jenkins, GitHub Actions, CI/CD, serverless, auto-scaling, zero-downtime deployments, disaster recovery
  • Databases & Caching: Oracle DB, PostgreSQL, MySQL, MongoDB, Redis, DynamoDB, query optimization, caching strategies, sharding, replication
  • Web & API: RESTful APIs, WebSocket, GraphQL, OAuth 2.0, JWT, RBAC, ABAC, OpenAPI/Swagger, gRPC, Nginx
  • Distributed Systems: Apache Kafka, event-driven architecture, microservices, circuit breakers, fault tolerance, high-availability design, legacy modernization, CQRS, DDD, clean architecture, monolith-to-microservices migration
  • Performance & Observability: Grafana, Prometheus, ELK, CloudWatch, New Relic, Sentry, P95 latency optimization, distributed tracing, MTTD optimization, memory-leak debugging, bundle analysis, CDN integration
  • Testing & QA: Jest, Cypress, JUnit, Mockito, Selenium, SonarQube, Postman, contract testing, TDD
  • Security: PCI DSS, OWASP Top 10, OAuth 2.0, JWT, RBAC, ABAC, CSP
  • AI & GenAI: LLM integration, prompt engineering, OpenAI API, scikit-learn, feature engineering, predictive analytics, recommendation systems
  • Agile & Collaboration: Agile/Scrum, Kanban, Jira, Confluence, sprint planning, SOLID, code reviews, technical mentoring, cross-functional collaboration, stakeholder management
  • Domain Expertise: FinTech (payments, subscriptions), e-commerce, SaaS platforms, enterprise analytics

Experience

Software Engineer · Capital One (CloudNest LLC) | USA Jun 2026 - Present
  • Financial-services platform serving millions of customers, supporting credit card, account-management, payment, and transaction services.
  • Developed Java/Spring Boot API functionality for credit-card servicing, account management, and transaction workflows, adding validation, error handling, and integrations with downstream services.
  • Enhanced React/JavaScript and Redux account-servicing workflows, improving transaction activity and account views while optimizing API calls and client-side rendering, reducing initial page load from 2.9s to 1.9s.
  • Improved API performance by tracing repeated PostgreSQL/MySQL reads and downstream calls; reworked queries and added Redis caching, reducing p95 response time from 510ms to 330ms.
  • Improved Kafka-based transaction and payment processing by adding retry, failure-handling, and recovery logic, reducing recurring processing failures from around 8 per month to 2 per month.
  • Implemented Spring Security, OAuth2, and JWT changes for account and transaction APIs, adding role-based access controls and consistent authentication across service workflows.
  • Resolved production issues across APIs, databases, and Kafka workflows, performing root-cause analysis and carrying fixes through testing and deployment using Docker, Jenkins, AWS EC2, and CI/CD pipelines.
Software Engineer · DoJoGa | USA Jul 2025 - May 2026
  • Developed Java/Spring Boot APIs for course availability and booking, using PostgreSQL transactions and validation to handle concurrent enrollment requests and prevent conflicting reservations during peak registration.
  • Built key parts of the React and TypeScript booking experience , course search, availability, enrollment, and confirmation flows , with improved client-side state handling and lazy loading for heavier views.
  • Reworked long-running enrollment processing with Kafka and AWS Lambda, moving independent tasks to asynchronous execution with retry and failure handling. End-to-end processing time dropped from ~2 hours to 10 minutes.
  • Designed indexing for booking and course-search queries and added Redis caching for read-heavy paths after tracing slowness to repeated PostgreSQL reads. p95 API latency dropped from 400ms to 150ms.
  • Built reusable React components for course cards, search filters, enrollment forms, and booking status views, consolidating shared validation and error handling across the booking flow.
  • Used GitHub Copilot and Claude in the workflow for refactoring, test creation, debugging, and code generation across Java and React, with all generated changes reviewed and validated before merging.
  • Containerized Java services with Docker and deployed on Kubernetes through Jenkins CI/CD using blue-green releases, and built a Python/scikit-learn forecasting pipeline to estimate capacity needs ahead of enrollment periods.
Software Engineer · OneDine (SakhaTech) | USA Sep 2022 - Jul 2023
  • Built end-to-end payment integrations with Amazon Pay, Global Payments, and Heartland, developing the React checkout experience and Node.js backend APIs for authentication, transaction processing, payment status updates, and failure handling.
  • Developed a real-time notification system using Node.js and WebSockets to surface transaction and operational events, helping cut support resolution time from ~2 hours to 25 minutes.
  • Traced frontend performance issues to unnecessary Redux updates and cascading re-renders; normalizing the store and adding memoized selectors brought page load from 3.2s to 1.9s for an app serving 50,000+ monthly active users.
  • Migrated key frontend workflows from Angular to React Hooks and built shared components in Storybook, reducing duplicated UI work and removing ~1.4 MB from the frontend bundle.
  • Moved public-facing pages from client-side rendering to Next.js server-side rendering so search engines could index them.
  • Mentored ~15 developers joining a new team building the company's in-house platform, setting foundations for React patterns, component structure, testing practices, and code-review standards.
Software Engineer · Adobe (Skrots) | India Feb 2019 - Aug 2022
  • Developed core parts of a React and TypeScript content-management experience , asset search, filtering, metadata editing, and bulk actions , extracting common table, form, and validation behavior into shared components reused across product workflows.
  • Built Java/Spring Boot APIs for content and analytics search, metadata, and workflow operations, cutting p95 response on key endpoints from 620ms to 390ms by optimizing MySQL queries and removing repeated downstream calls.
  • Implemented Spring Security, OAuth2, and JWT-based authorization across customer-facing and internal APIs, consolidating duplicated authentication logic and standardizing role-based access checks.
  • Maintained Angular and RxJS modules while newer UI moved toward React, simplifying observable chains and removing duplicate subscriptions and requests causing stale data and unnecessary refreshes.
  • Improved a slow React analytics dashboard by tracing repeated renders and duplicate API requests; request caching, memoization, and lazy loading brought initial load from 4.8s to 2.9s on larger datasets.
  • Added Redis caching for frequently accessed content metadata, moved a content-processing workflow to Kafka async processing (~8 minutes to under 3), containerized services with Docker/Kubernetes, and cut the main CI pipeline from ~32 to 19 minutes.

Education & Certification

Master of Science, Data Science · University of Texas at Arlington , Arlington, TX, USA Aug 2023 - May 2025
Bachelor of Engineering, Computer Science and Engineering · RNS Institute of Technology , Bengaluru, India Aug 2015 - Jul 2019

Certifications: Front End Web Developer Nanodegree I & II , Udacity (co-created by AT&T, Google, and GitHub)

⬇ download resume.pdf
Notes File Edit View Help
🔋
,
~/manoj.dev/notes.txt
~ notes ~

Hi, I'm Manoj.

welcome to my desk ↓

status
open to roles
experience
5+ years
reach me
manojka.swe@gmail.com
Software engineer who likes the hard parts: full-stack apps, event-driven systems, and performance work. 5+ years shipping React/TypeScript front ends and Java/Spring Boot services at scale, currently building credit-card and transaction services for Capital One.

I'm a software engineer who builds full-stack applications that have to hold up under real load. I work across the stack , React, TypeScript, Next.js, Angular on the front end and Java, Spring Boot, Node.js, Kafka, REST/GraphQL on the server side , backed by PostgreSQL, Redis, DynamoDB. Cloud-native by default: AWS, Docker, Kubernetes, CI/CD.

I've done this at Capital One (credit-card servicing and transaction APIs), DoJoGa (a course booking platform with Kafka/Lambda pipelines and demand forecasting), OneDine (payment integrations and real-time notifications), and Adobe (content-management front ends and backend search/metadata APIs). Payments, booking, and content platforms , same underlying problems.

Things I care about: event-driven systems that don't drop or duplicate work, front ends that stay fast as data grows, AI woven in carefully (LLM-assisted tooling grounded in real, access-controlled data), and getting latency down by measuring where the work actually goes. I'm the engineer who took p95 from 510ms to 330ms and recurring processing failures from 8 a month to 2 by tracing the real cause.

⚡
currently
Software Engineer for Capital One (via CloudNest). Building credit-card and transaction services in React/Redux and Java/Spring Boot, tuning API performance, and hardening the Kafka payment flow. Open to conversations about full-stack, fintech, and performance problems.
~ m.

by the numbers

0
p95 transaction API latency, down from 510ms at Capital One
0
Kafka processing failures, down from 8 per month at Capital One
0
monthly active users served on the OneDine platform
0
p95 API latency on the DoJoGa booking platform, down from 400ms
manoj@desk:~/playgrounds$ ./run --interactive
loading 3 live demos...

click things. break things.

three systems problems you'll hit the moment you have more than one user. payments, healthcare, messaging, analytics , same hard parts. try to break them.

01. webhook idempotency

LIVE

any webhook source , Stripe, GitHub, Twilio, Shopify, your own services , will retry if you don't ack in time. your job: process exactly once. strategy: every event carries an event_id, you cache what you've processed. try hitting "duplicate" a bunch.

0processed
0dropped
$0total charged

02. exponential backoff + jitter

LIVE

some downstream service , a database, a payment processor, an EHR, a third-party API , flakes out 60% of the time. retry up to 5 times with base · 2^n + jitter. jitter prevents the thundering herd. every run is different.

0attempts
0mselapsed
,result
// hit run to start

03. token bucket rate limiter

LIVE

every API needs one. capacity 10, refill 2/sec. each request spends a token. empty → 429. try to spam faster than it refills.

0200 ok
0429
10tokens
bucket10/10
manoj.dev › work › experience

where i've worked.

4 roles · 5+ years · full-stack, fintech, and platform work.

Software Engineer · CloudNest LLC
Capital One
'26 → now
2.9s→1.9s
page load
510→330ms
p95 latency
8→2/mo
processing failures

Working on a financial-services platform serving millions , credit-card servicing, account management, payments, and transactions. Built Java/Spring Boot APIs with validation and downstream integrations, enhanced React/Redux account-servicing views (page load 2.9s to 1.9s), traced slow reads and added Redis caching (p95 510ms to 330ms), and hardened the Kafka payment flow with retry/recovery (failures 8 to 2 a month).

Software Engineer
DoJoGa
'25 - '26
2h→10m
enrollment processing
400→150ms
p95 API latency
ML
demand forecasting

Built a course booking platform end to end , Spring Boot APIs + React/TypeScript flows. Moved enrollment processing to Kafka + Lambda (2 hours to 10 minutes), cut p95 latency from 400ms to 150ms, and built a Python/scikit-learn pipeline forecasting capacity ahead of enrollment.

Software Engineer · SakhaTech
OneDine
'22 - '23
3.2s→1.9s
page load
50K+
monthly active users
~15
devs mentored

Integrated 3 payment gateways (Amazon Pay, Global Payments, Heartland) with a React checkout and Node.js APIs. Cut page load from 3.2s to 1.9s for 50K+ MAU, built real-time WebSocket notifications, migrated Angular to React Hooks, and mentored ~15 developers.

Software Engineer · Skrots
Adobe
'19 - '22
620→390ms
p95 response
8m→<3m
content processing
32→19m
CI pipeline

Built a React/TypeScript content-management experience and the Java/Spring Boot search + metadata APIs behind it. Cut p95 from 620ms to 390ms, sped a slow dashboard from 4.8s to 2.9s, moved content processing to Kafka async (8 min to under 3), and trimmed CI from 32 to 19 minutes.

things I can actually do.

grouped by what I reach for. not a wishlist. not a buzzword cloud.

🧠 languages
Java Python C / C++ JavaScript TypeScript SQL
🎨 frontend
React Redux Next.js RxJS Tailwind HTML/CSS
⚙️ backend
Spring Boot Spring Cloud Node.js Express REST GraphQL
🤖 AI / ML
LLMs RAG AWS Bedrock OpenAI APIs Tool calling Embeddings & vector search Agent architecture Prompt engineering
📡 data & messaging
Kafka Redis PostgreSQL MySQL MongoDB
☁️ cloud & devops
AWS Docker Kubernetes GitHub Actions CI/CD
🎯 production practices my thing
Idempotency Rate limiting Retries with jitter Circuit breakers OAuth2 / JWT Observability

things i've built.

8 items
● personal ● worked at
personal
🔍
reviewlens
a voice-of-customer decision engine.
turns customer reviews and feedback into actionable insights. built to surface what users actually think, prioritize the signal, and help teams make data-driven product decisions.
+ tap to learn more
personal
🪐
code-orbit
a playground for exploring code concepts visually.
an experimental space for visualizing algorithms, data structures, and computer-science ideas in the browser. designed to make abstract things tangible.
+ tap to learn more
personal
🎮
arcade-game
a browser arcade game, built just for fun.
a classic arcade-style game running entirely in the browser. demonstrates game-loop fundamentals, collision detection, and responsive input handling.
+ tap to learn more
worked at
🏦
capital one
credit-card & transaction services.
a financial-services platform serving millions , credit-card servicing, account management, payments, and transactions. Built Java/Spring Boot APIs with validation and downstream integrations, enhanced React/Redux account-servicing views (page load 2.9s to 1.9s), reworked queries and added Redis caching (p95 510ms to 330ms), and hardened the Kafka payment flow with retry/recovery (failures 8 to 2 a month).
+ tap to learn more
worked at
🥋
dojoga
course booking platform with ml forecasting.
a course booking platform , Java/Spring Boot availability and booking APIs with PostgreSQL transactions to prevent double-booking at peak, plus a React/TypeScript search-to-confirmation flow. Moved enrollment processing to Kafka + AWS Lambda (2 hours to 10 minutes), cut p95 API latency from 400ms to 150ms with indexing and Redis, shipped via Jenkins blue-green releases, and built a Python/scikit-learn pipeline forecasting capacity needs ahead of enrollment.
+ tap to learn more
worked at
🍽️
onedine
payments & real-time notifications.
end-to-end payment integrations with Amazon Pay, Global Payments, and Heartland , a React checkout and Node.js APIs for auth, processing, status, and failure handling. Built a Node.js + WebSockets notification system (support resolution 2 hours to 25 minutes), cut page load from 3.2s to 1.9s for 50K+ MAU by normalizing Redux and memoizing selectors, migrated Angular to React Hooks with Storybook (~1.4 MB off the bundle), and moved public pages to Next.js SSR.
+ tap to learn more
worked at
🎨
adobe
content-management front end & search apis.
a React/TypeScript content-management experience , asset search, filtering, metadata editing, and bulk actions , with Java/Spring Boot APIs for content and analytics search. Cut p95 response from 620ms to 390ms on key endpoints, standardized OAuth2/JWT role-based access, sped a slow analytics dashboard from 4.8s to 2.9s, moved content processing to Kafka async (~8 minutes to under 3), and trimmed the CI pipeline from 32 to 19 minutes.
+ tap to learn more
personal
this site
an interactive desk portfolio you're using right now.
an interactive desk experience with draggable items, a fake operating system inside the laptop, three live playgrounds, achievements, drawing mode, and a hidden drawer. you're inside it.
+ tap to learn more
🎧
NOW PLAYING
life outside work
manoj · hobbies playlist
0:00 ∞

manoj's life outside work

the playlist that runs when the laptop is closed · 7 tracks

1
🍜
cooking new recipes
the kitchen sessions
1,847 plays
4:32
2
🎮
video games
console and keyboard
2,398 plays
6:12
3
📺
tv, but responsibly
one more episode
1,204 plays
3:48
4
💪
the gym
mon/wed/fri, mostly
588 plays
3:02
5
🌐
building websites for fun
sites like this one
412 plays
5:17
6
🍽
exploring restaurants
a new place every week
306 plays
2:48
7
✈️
weekend travels
anywhere < 4 hours away
156 plays
5:21
MK
Manoj Kumar ● online · usually replies fast
hey manoj 👋
saw your portfolio. you made a desk? today · just now
yep. it was more fun than a landing page. today · just now
fair. we're hiring senior full-stack. strong systems engineers only. interested? today · just now
definitely. let's talk. today · just now
say hi↗
reply times are fast. usually.
email call linkedin github resume.pdf
🗒Notes
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