Karthick Devaraj
Java Backend Developer · 7+ Years · Chennai, India
📧 [email protected] · 🔗 LinkedIn
What I Do
I specialize in designing microservices architectures that are built to last—systems that handle complexity gracefully, integrate with external APIs reliably, and scale without falling apart.
My core expertise spans Java 8/11, Spring Boot, MongoDB, MySQL, and cloud infrastructure on AWS. I’ve worked across domains—travel tech, fintech, and edtech—which means I understand that good backend engineering isn’t just about code; it’s about solving business problems.
Professional Experience
SDE 3 · PickYourTrail
December 2022 – Present · Chennai, India
PickYourTrail is one of India’s leading travel platforms, and I work at the heart of its backend infrastructure.
Hotel Microservice Architecture I architected and developed the hotel microservice that handles the complete booking workflow—from search to confirmation. This isn’t a simple CRUD service; it orchestrates multiple external providers, manages inventory in real-time, and handles the complexity of international hotel bookings.
- Integrated 5 external API providers to dramatically expand hotel inventory for both inbound and outbound travel
- Built robust error handling and retry mechanisms that enabled 4,000+ automated bookings without manual intervention
- Implemented circuit breakers and fallback strategies to ensure the system stays responsive even when third-party APIs fail
- Designed asynchronous processing pipelines for handling high-volume booking requests during peak travel seasons
- Led performance optimization initiatives—caching strategies, database query optimization—reducing latency and minimizing downtime
Unity Module: End-to-End Itinerary Builder Built from the ground up, Unity is an internal platform that empowers PickYourTrail’s sellers to curate and sell complete travel packages.
- Supports multi-city itineraries with diverse entities: hotels, activities, transfers, rental cars, and ferries
- Developed a dynamic pricing engine that calculates costs across different package configurations in real-time
- Built real-time inventory tracking that syncs availability across all integrated providers
- Implemented offer management and cancellation policy modules with instant campaign publishing to the PickYourTrail website
- Created multi-combination itinerary display letting sellers visualize and compare different package options
Member Technical Staff · Zoho Corporation (Zoho Finance - Zoho Books)
July 2021 – November 2022 · Chennai, India
At Zoho, I worked on one of India’s most critical business compliance challenges: GST filing.
Zoho GST Application Led backend implementation for the GST application that helps MSMEs and enterprises manage their tax filings efficiently.
- Built comprehensive support for GSTR1, GSTR2, GSTR3B, and GSTR9 filings—each with its own complexity and regulatory requirements
- Implemented complex business logic for tax calculations, invoice generation, and automated filing workflows
- Designed systems to handle large volumes of transaction data while maintaining accuracy required for regulatory compliance
Zoho GSP (GST Suvidha Provider) & ASP Services Developed Zoho’s GST Suvidha Provider platform—one of the providers authorized by GSTN (Goods and Services Tax Network) to facilitate GST compliance.
- Built RESTful APIs that seamlessly integrate GST services with Zoho Books
- Implemented secure API integration with GSTN for real-time data synchronization and filing submissions
- Created audit trails and logging mechanisms ensuring data integrity and regulatory compliance
- Collaborated closely with compliance and product teams to adapt to evolving GST regulations
Senior Engineer · Infosys Limited
August 2018 – June 2021 · Mysuru, India
At Infosys, I worked at the intersection of emerging technologies and education—building interactive learning experiences for cutting-edge domains.
Autonomous Vehicle Learning Platform Developed gamified learning content that made complex autonomous vehicle concepts accessible and engaging.
- Created interactive simulations demonstrating computer vision algorithms, object detection, and path planning techniques
- Built comprehensive courseware covering PID controllers, sensor fusion, and decision-making systems for self-driving vehicles
- Published content on web platforms reaching learners exploring autonomous technology
AR/VR Development Led development of immersive applications that visualized complex technical concepts.
- Built standalone AR/VR applications for Universal Windows Platform
- Handled end-to-end development: 3D modeling in Blender, game design, and C# scripting in Unity
- Created experiences that transformed abstract autonomous vehicle concepts into tangible, explorable environments
Educator Training Program Trained 300+ educators on game development fundamentals—an experience that shaped how I think about knowledge transfer and documentation.
- Covered player controls, sound integration, UI design, and advanced C# scripting
- Developed training materials that broke down complex Unity concepts into teachable modules
Key Projects
Hotel Services Microservice
Tech Stack: Java 11, MongoDB, Spring Boot, Maven, Jenkins, Docker, Kubernetes, AWS, ElasticSearch
A production system handling real bookings, real money, and real customer expectations.
- Domain-driven design architecture ensuring scalability and maintainability as the system grows
- Resilient integration patterns: circuit breakers, retry mechanisms, fallback strategies for third-party API failures
- CI/CD pipelines using Jenkins for automated testing and deployment to Kubernetes clusters on AWS
- ElasticSearch integration for fast, flexible hotel search across millions of properties
Zoho GST Tax Filing Platform
Tech Stack: Java 8, MySQL 5.7, Spring Boot, Gradle, Git
Enterprise-grade tax compliance serving businesses across India.
- Optimized database schemas handling large transaction volumes while maintaining query performance
- Real-time synchronization with GSTN ensuring filing accuracy and compliance
- Comprehensive audit logging for regulatory requirements and data integrity
Gamified Learning & AR/VR for Autonomous Vehicles
Tech Stack: Unity 3D, Blender, C#, Visual Studio
Making autonomous vehicle technology accessible through interactive experiences.
- Interactive simulations demonstrating computer vision and path planning algorithms
- Immersive AR/VR experiences for visualizing complex autonomous systems
- Published courseware and conducted training programs for educators
Technical Skills
Languages Java 11/8 · JavaScript · Python · C# · Shell Scripting
Backend & Frameworks Spring Boot · Hibernate · RESTful API Design · Microservices Architecture
Databases MongoDB · MySQL · RDBMS · ElasticSearch
Cloud & DevOps AWS · Docker · Kubernetes · Jenkins · Git · CI/CD Pipelines · UNIX
Tools & Platforms Maven · Gradle · Selenium · JIRA · MS PowerApps
AI & Development Tools GitHub Copilot · Claude Code · OpenRouter · n8n · OpenAI APIs
Specialized Unity 3D · OpenCV · Blender · AR/VR Development
Education
Bachelor of Engineering in Automobile Engineering PSG College of Technology, Coimbatore · 2014 – 2018 CGPA: 8.81/10
Recognition
🏆 Rookie of the Quarter · PickYourTrail, April 2023 Recognized for successful integration of third-party API providers. Awarded by Hari Ganapathy, Co-Founder.
🏆 Insta Award · Infosys, December 2019 Recognized for contributions to autonomous technologies and AR/VR initiatives. Awarded by Thirumala Arohi, VP-Head ETA.
📜 Infosys Certified Java Programmer · April 2021
Let’s Connect
I’m always open to discussing backend architecture, system design, or interesting engineering challenges.
Whether you’re building something in travel tech, need help scaling microservices, or just want to talk shop about Java and distributed systems—reach out.