Oct 2022 – Present · 3 yrs 5 mos

• I was a founding member of the Outbound Campaign Management product for Webex Contact Center, contributing from the architecture design phase to production support. I designed and implemented core backend modules for preparing and processing large-scale dial lists, built a stateless authentication layer with robust session management, and implemented compliance rules based on U.S. state laws to prevent user defined off-hour calling and manage call frequency strategies. I developed multi-contact mode, rule-based dial suppressions using Spring Expression Language (SpEL), and designed a dynamic query builder to transform user-defined filters into optimized MongoDB queries. To ensure scalability and data consistency, I implemented distributed locking using Redisson, optimized MongoDB queries through load testing, and introduced bulk write operations with version-based optimistic locking.
• Worked on building an API Management Portal on top of the AWS API gateway using OpenAPI 3.0 specification and Javascript AWS Client SDK. Implemented API Gateway Authorizer, Throttle Control using Redis, and RBAC using Keycloak OAuth Client Credentials Flow. All the backend applications ( Node.js ) were Serverless using AWS Lambda, Front end (React.js ) on the Edge optimized Cloudfront distribution.
• Micro-Frontend: Built reusable Custom Tag-based Web components for Microservices using Angular Custom Elements with Shadow DOM.
• Worked on building a multi-tenant URL Shortner microservice with many custom features like Expiry, OS, and Device-based routing, Personalizations. Tracking the link and pushing the metadata into Apache Kafka topic which is consumed and pushed to various other data sources.
• Created an automation framework for the QA automation team in Cucumber BDD & JAVA Selenium. This resulted in automating a complex UI involving Drag&Drop builder and thereby reducing man hours of QA during Sanity and Regression testing.

Oct 2021 – Oct 2022 · 1 yr

• Worked on building a near real-time Centralized Transactions Repository with Apache Kafka (AWS MSK), Kafka Connect File Pulse, AWS Document DB, Lambda, S3, Guava Cache. This was a cross-product solution to allow customers to get the transactions stored in Files and Redshift. The TPS was improved from 7/sec to 320/sec using Batch Kafka polling, Multi-threaded processing, Batch upsert to the Database.
• Developed a AWS Lambda serverless PDF Service in Node.js to generate personalized PDFs from the HTML using JavaScript runtime library Puppeteer, resulting significant cost savings against using a 3rd party service.
• Worked on migrating the transaction logs from RDS to S3 and querying through AWS Athena. This resulted in significant cost savings due to logs of size 1TB/month stored in RDS. Implemented Partition projections on a granularity level of minute-wise partitions which reduced the data scan size by more than 50GB in every Athena query resulting in improved performance and more cost-effective.
• Developed a AWS Lambda service in Python to convert the log files stored in S3 to the Apache Parquet file format which stores the data in columns, using snappy compression. Used S3 triggers to invoke lambda. This significantly reduced our AWS Athena data scan size costs by 90%. Used pandas and pyarrow libraries for processing the parquet files.
• Developed the Jenkins Declarative pipeline scripts for the build and deployment lifecycle of 120+ apps. Simplified the build stage by converting all the apps from Ant to Maven. Used AWS CDK to synthesize the EKS cluster creation and automated the deployment of ALB ingress controller, IAM RBAC, application pods. Fine tuned the Horizontal Pod Autoscalar ( HPA ) for resource optimization.

Mar 2019 – Sep 2021 · 2 yrs 6 mos

• Developed a JAR and integrated with SVN Pre-commit hook which will read the developer’s local modified files and publish to Sonarqube server and then restrict the commit if the SonarQube code quality gate was a failure. This was later used across all the teams in all developers’ machines to help check the code quality of individual developers.
• Worked on Wildfly 16 server to do the session replication when two or more Wildfly servers are running in a distributed cluster on two different physical devices. Infinispan was used to handle the distributed session level cache between the servers along with JGroups.
• Worked on Angular 7 application to improve the performance and load time for about 70%. Load time of the application was significantly decreased from 30+seconds to <5 seconds. Implemented the tree shaking and optimized builds using the JIT compilation. Implemented gzip compression on the NGINX server which further reduced the file transfer size by 50% over the network.
• Developed Proxy WAR for Multiple Identity Provider based SAML Authentication which was used across the teams for the client integration. Supported for Idps like Microsoft Azure, Okta.
• Designed and implemented Role based authorization to APIs in Spring using cached Role Permissions. Implemented Auth Guard in Angular 7 to authorize routes based on Role. Implemented a reusable directive to conditionally hide/show elements based on permissions attached to the route.
• Addressed all OWASP security principles in our APIs and UI. (XSS, SQL Injection, CSRF token etc). Built Spring Filters and Interceptors to handle these.
• Involved in multiple development activities with developing the UI in Angular and APIs in Spring.