Sonu Kumar S

Java Backend Developer with 3+ years of experience building scalable microservices and cloud-native applications using Java, Spring Boot, and AWS (primary cloud), with additional Azure exposure (SSO/Azure AD). Proven hands-on experience developing and consuming RESTful APIs, containerising workloads with Docker, and contributing to CI/CD pipelines (Jenkins, GitHub Actions). Strong focus on application security (JWT, OAuth2, IAM), performance monitoring and troubleshooting (CloudWatch, X-Ray), and NoSQL databases (MongoDB, DynamoDB).

Full Stack Java Developer at Mahindra & Mahindra (2023-08 – Present)

• Microservices development: Designed and built production-grade microservices using Java and Spring Boot, deployed on AWS ECS, EC2, and Lambda; developed 10+ RESTful APIs powering procurement workflows across 3 cross-functional teams, improving modularity and independent deployability.
• CI/CD contribution: Contributed to Jenkins and GitHub Actions CI/CD pipelines – added build stages, integrated automated test runs, and supported containerised deployments with Docker; worked within Kubernetes (EKS) environments for service deployments and scaling.
• Performance troubleshooting: Diagnosed and resolved production latency issues using AWS X-Ray and CloudWatch; identified N+1 query patterns and connection-pool exhaustion, reducing p99 API response time by ∼35%.
• AWS service configuration: Provisioned and managed AWS RDS (PostgreSQL), DynamoDB, S3, and API Gateway; enforced data security through IAM roles and KMS encryption, meeting compliance requirements.
• Serverless automation: Engineered event-driven AWS Lambda + Step Functions workflows integrated with Kafka to automate report generation, reducing batch processing time from days to under 10 minutes.
• Security & quality: Implemented OAuth2/JWT authentication, wrote comprehensive API documentation (Swagger/OpenAPI), authored Terraform scripts for infrastructure provisioning, and maintained 90%+ JUnit unit test coverage.
• Full-stack delivery: Built responsive React + TypeScript frontends integrated with backend microservices; conducted code reviews and followed Agile/Scrum practices, consistently delivering sprint commitments on schedule.

Software Development Intern at Motorola Solutions (2022-07 – 2023-07)

• Built Spring Boot RESTful APIs for mission-critical public safety systems, integrating with PostgreSQL relational and MongoDB NoSQL data stores; maintained high test coverage with JUnit.
• Contributed to Jenkins CI/CD pipeline configuration – added automated test stages and supported deployment scripts, improving release reliability across environments.

Bachelor of Engineering in Computer Science – HKBK College of Engineering (2019-08 – 2023-06)