Karthick SG
Senior Software Engineer II — JavaScript, React, Node.JS & GraphQL
karthisg.dev@gmail.com
+91 90951 69428  ·  Madurai, TN (Open to Remote / Hybrid)
linkedin.com/in/karthisgdotsg
github.com/karthisgk  ·  karthisgk.github.io

Technical Leader & Senior Full Stack JavaScript Engineer with 8 years of web development experience (5+ years in senior roles), specializing in React, Redux, Node.js, GraphQL, and Express. Proven track record leading end-to-end web development on agile cross-functional teams, translating business goals into scalable, accessible, and fault-tolerant solutions. Recognized for optimizing web application latency and accessibility (WCAG 2.1 AA, Web Vitals), strengthening deployment confidence through test automation (Jest, React Testing Library, Cypress), and partnering closely with Site Reliability Engineering (SRE) teams to resolve complex production incidents. Active mentor and open-source author with 3 published npm packages (1,000–5,000+ downloads) and production AI/LLM experience.

Core Skills & Technologies
JavaScript (ES6+) · TypeScript · Node.js
React.js · Redux Toolkit · State Management
GraphQL · REST APIs · Express.js · Apollo
Jest · React Testing Library · Cypress
Web Vitals · Performance · Accessibility (WCAG)
SRE Telemetry · Incident Resolution · Reliability
Microservices · NestJS · Modular Architecture
CI/CD Pipelines · GitHub Actions · Docker
MongoDB · PostgreSQL · Redis Caching
Azure (Functions, IaC) · AWS Cloud
OAuth 2.0 · JWT · Security & Compliance
Technical Mentorship · Code Reviews · Pair Programming
Agile / Scrum · DevOps Principles · Automation
AI Integration · Claude API · MCP Protocol
Professional Experience
Senior Software Engineer — Technical Lead (Full Stack & Node.js/React)
Dec 2022 – Present · 3+ yrs
Techversant Infotech Pvt. Ltd.
JavaScript · React · Redux · Node.js · GraphQL · Express · Jest · Azure · SRE Collaboration
  • Led end-to-end web application development across 3–5 microservices utilizing React, Node.js, and GraphQL API gateways, translating complex product requirements into high-availability technical architecture.
  • Mentored cross-functional engineering teams through structured daily code reviews, pair programming sessions, and developer experience refinements, elevating overall team code quality and delivery velocity.
  • Optimized application performance and accessibility: reduced frontend bundle size by 35%, achieved Web Vitals LCP < 1.8s, and ensured full WCAG 2.1 AA compliance for high-impact user flows.
  • Boosted deployment confidence & test coverage by architecting automated CI/CD pipelines (GitHub Actions) with Jest and React Testing Library, reducing release cycles from 30 min to under 5 min (~83% faster).
  • Collaborated with SRE teams to triage and resolve production incidents: implemented distributed tracing, telemetry monitoring, and fallback strategies to guarantee 99.9% uptime.
  • Pioneered automated infrastructure & integration testing using Azure IaC (Bicep) and Docker, eliminating 4+ hours of manual deployment setup per sprint across staging and production.
Software Engineer — Frontend & API Development
Aug 2021 – Nov 2022 · 1 yr 4 mo
AES Technologies India Pvt. Ltd.
JavaScript (ES6+) · React · Redux · Node.js · Express · GraphQL · REST APIs · OAuth 2.0
  • Engineered responsive, highly performant React UIs utilizing Redux for state management, custom hooks, and component modularity to deliver customer-centric, frictionless web experiences.
  • Built scalable GraphQL and RESTful backend APIs in Node.js/Express with OAuth 2.0 and JWT security, managing high-concurrency requests with efficient schema resolvers and caching.
  • Integrated Singapore national Singpass digital identity verification under strict security, data privacy, and government regulatory compliance standards.
  • Authored and published 3 internal npm libraries to standardize UI component design tokens and utilities across multi-functional development teams, cutting redundant UI work by 40%.
  • Partnered with Product Owners in Agile sprints to define technical user stories, refine acceptance criteria, and drive continuous developer experience improvements.
Software Developer — Web & Backend Systems
Jun 2020 – Jul 2021 · 1 yr 2 mo
DDL Tech Solutions Pvt. Ltd.
JavaScript · React · Node.js · Express · MongoDB · REST APIs · Agile
  • Developed scalable full-stack web applications using JavaScript, React, Node.js, and MongoDB for enterprise clients in accounting and operations domains.
  • Optimized MongoDB database schemas and index structures for high-frequency transactional data, improving query response latency by 45%.
  • Designed role-based access control (RBAC) security frameworks and REST API endpoints to enforce precise permission management and data isolation.
Notable Projects
MCP Financial & Expense Engine (AI-Powered)
TypeScript · Node.js · GraphQL/REST · Claude API · MCP
Built a production-grade Model Context Protocol (MCP) server enabling natural language query processing for financial transaction management. Integrated structured tool schemas, SSE transport, and secure API integration.
Open-Source npm Packages (3 Published)
JavaScript · React · TypeScript · CSS Architecture · npm
Authored 3 open-source libraries: satti-table (data table), react-satti-chart (visualization), and react-pendulum-loader (accessible UI loader), accumulating 1,000–5,000+ total downloads.
High-Traffic Card Shop & E-Commerce Web Apps
React · Redux · Node.js · Express · Web Vitals · WCAG
Architected performant React frontend user flows backed by Node.js API gateways, optimized for customer acquisition, fast page loads (<1.8s LCP), cross-browser compatibility, and strict WCAG accessibility standards.
Multi-Tenant Financial & Healthcare Platform
Node.js · NestJS · GraphQL · Azure · Docker · Kafka
Designed multi-tenant microservices backend handling high-volume transaction event streams, distributed logging, SRE alerting telemetry, and zero-downtime CI/CD deployment pipelines.
Education & Certifications
Master of Computer Applications (MCA)
KLN College of Engineering, Madurai  ·  2018–2020
B.Sc. Information Technology
Sourashtra College of Arts & Science, Madurai  ·  2014–2017
Senior JavaScript & Web Performance Certification (2025)
Open-Source Author & Contributor — 3 published npm packages (1k–5k+ downloads)