Collaborated and paired with team members to develop Home Depot's new loyalty service for professional customers as part of the business initiative to increase revenue by $20B by the end of 2020. The service runs on Google Cloud Platform. The service is deployed to production and available to professional customers at Home Depot retail stores as of 2019. This replaces the old ProXtra service.Wrote custom code to extract, transform, and load 7TB of customer data from the ProXtra legacy service to the new loyalty service. The data included customers' membership statuses, enrolled programs, tier levels, and qualifying purchases. The migration also included existing ProXtra programs and rewards. The data was migrated from an on-premise DB2 database to Google Cloud Spanner using Google Dataflow.Worked with the Product and Project team to design APIs to support CRUD operations of loyalty programs, program's tiers, and tier rewards. Implemented the APIs using Spring Boot.Designed, Deployed, and maintained a Knowledge Graph Database for search application. The database contains over 300 GB of catalog data to enable searches using natural language queries. The database runs on Datastax Enterprise (DSE) Graph.Wrote automation scripts to upgrade production database clusters to DSE version 6.0.9 and then to version 6.7.5 and Ubuntu 18 with no cluster downtime. Optimized Big Query usage across more than 100 projects at Home Depot without any additional costs. In the optimization, I prioritized projects so that time sensitive projects could borrow resources from projects whose jobs can be delayed by a few hours.Automated scaling of nodes used in Google Cloud Spanner and Bigtable for cost optimization.Implemented database changes to allow purchase of tinted paint using Buy Online Pickup In Store (BOPIS) option as part of Home Depot’s social distancing policies during Covid-19.