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I’m a Senior Software Engineer with 4.5+ years of experience building scalable frontend and full-stack products at HackerRank. I helped build SkillUp from the ground up, led frontend initiatives across a team of engineers, improved performance and accessibility across multiple applications, and worked extensively with React, Next.js, TypeScript, Node.js, Java, and distributed systems. I enjoy owning products end to end, solving complex engineering problems, and building reliable user experiences at scale.…I’m a Senior Software Engineer with 4.5+ years of experience building scalable frontend and full-stack products at HackerRank. I helped build SkillUp from the ground up, led frontend initiatives across a team of engineers, improved performance and accessibility across multiple applications, and worked extensively with React, Next.js, TypeScript, Node.js, Java, and distributed systems. I enjoy owning products end to end, solving complex engineering problems, and building reliable user experiences at scale.

Karan Shah

Full Stack Developer, AI Engineer, Back-End Developer

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I’m a Senior Software Engineer with 4.5+ years of experience building scalable frontend and full-stack products at HackerRank. I helped build SkillUp from the ground up, led frontend initiatives across a team of engineers, improved performance and accessibility across multiple applications, and worked extensively with React, Next.js, TypeScript, Node.js, Java, and distributed systems. I enjoy owning products end to end, solving complex engineering problems, and building reliable user experiences at scale.…I’m a Senior Software Engineer with 4.5+ years of experience building scalable frontend and full-stack products at HackerRank. I helped build SkillUp from the ground up, led frontend initiatives across a team of engineers, improved performance and accessibility across multiple applications, and worked extensively with React, Next.js, TypeScript, Node.js, Java, and distributed systems. I enjoy owning products end to end, solving complex engineering problems, and building reliable user experiences at scale.

Available to hire

I’m a Senior Software Engineer with 4.5+ years of experience building scalable frontend and full-stack products at HackerRank. I helped build SkillUp from the ground up, led frontend initiatives across a team of engineers, improved performance and accessibility across multiple applications, and worked extensively with React, Next.js, TypeScript, Node.js, Java, and distributed systems. I enjoy owning products end to end, solving complex engineering problems, and building reliable user experiences at scale.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Language

Javanese

Advanced

Work Experience

Senior Software Engineer at HackerRank

August 1, 2024 - February 1, 2026

Engineering lead for HackerRank SkillUp, driving roadmap execution across a team of 6+ engineers, supporting 15k+ MAU and generating $8M+ ARR. Improved frontend performance by ~40% (LCP < 2s, CLS < 0.1) via migration from Webpack to Rspack across 7 repos, reducing build times by 50%. Designed a fault-tolerant asynchronous worker using BullMQ and Redis to process 150k+ daily events across assessment and learning workflows. Reduced P95 API latency by 30–50% to sub-250ms through indexing, connection pooling, Redis caching, and N+1 query fixes in Spring Boot services. Built OAuth2/SSO and bidirectional ATS integrations to synchronize assessment and learning data via REST APIs. Worked on audit logging and image-processing pipelines with Kafka, Spark, Hudi, Python, and Redis. Delivered Redis-backed leaderboards and caching layers to improve read performance by 60%. Led accessibility improvements (WCAG violations reduced from 3,000+ to 1,000), mentored engineers/interns, and conducted 70+ t

SDE II at HackerRank

April 1, 2023 - July 1, 2024

Founding engineer for HackerRank SkillUp, building the product from 0 to 1 in collaboration with Product, Design, and leadership. Built an AI-powered Socratic Tutor using LLM guardrails and persistent learner memory, improving lesson completion by 45% across 10k+ learners. Architected the frontend platform with Next.js and created a reusable starter template standardizing routing, state management, testing, accessibility, and performance across 10+ applications. Built backend services using Java, Spring Boot, and Hibernate with REST APIs and improved query performance for learning workflows. Implemented a plugin-based authoring platform using Lexical with templates, media uploads, and reusable content blocks.

SDE I at HackerRank

January 1, 2022 - March 1, 2023

Core contributor to HackerRank's design system, enabling consistent and accessible experiences across 20+ product lines. Migrated legacy Backbone applications to React and contributed to Spring Boot/Hibernate APIs, improving maintainability and developer productivity. Migrated legacy test suites to Jest and React Testing Library and mentored interns.

Software Engineer Intern at HackerRank

July 1, 2021 - December 1, 2021

Developed reporting and analytics interfaces used by enterprise customers. Increased frontend quality by raising test coverage from 68% to 93%. Reduced open support tickets by 60% through systematic bug fixing and production issue resolution.